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We have recently identified the hADA3 protein, the human homologue of yeast transcriptional coactivator yADA3, as a novel HPV16 E6 target. Using ectopic expression approaches, we further demonstrated that hADA3 directly binds to the 9-cis retinoic acid receptors alpha and beta, and functions as a coactivator for retinoid receptor-mediated transcriptional activation. Here, we examined the role of endogenous hADA3 as a coactivator for estrogen receptor (ER), an important member of the nuclear hormone receptor superfamily. We show that ADA3 directly interacts with ER alpha and ER beta. Using the chromatin immunoprecipitation assay, we also show that hADA3 is a component of the activator complexes bound to the native ER response element within the promoter of the estrogen-responsive gene pS2. Furthermore, using an ER response element-luciferase reporter, we show that overexpression of ADA3 enhances the ER alpha- and ER beta-mediated sequence-specific transactivation. Reverse transcription-PCR analysis showed an ADA3-mediated increase in estrogen-induced expression of the endogenous pS2 gene. More importantly, using RNA interference against hADA3, we demonstrate that inhibition of endogenous hADA3 inhibited ER-mediated transactivation and the estrogen-induced increase in the expression of pS2, cathepsin D, and progesterone receptor, three widely known ER-responsive genes. The HPV E6 protein, by targeting hADA3 for degradation, inhibited the ER alpha-mediated transactivation and the protein expression of ER target genes. Thus, our results demonstrate that ADA3 directly binds to human estrogen receptor and enhances the transcription of ER-responsive genes, suggesting a broader role of mammalian hADA3 as a coactivator of nuclear hormone receptors and the potential role of these pathways in HPV oncogenesis.

A cost analysis to compare high dose rate (HDR) brachytherapy using either californium-252 (252Cf) or 192Ir was performed to determine the prospects of widespread clinical implementation of HDR 252Cf. Interest in the neutron-emitting 252Cf radioisotope as a radiotherapy nuclide has undergone a resurgence given recent efforts to fabricate HDR remotely afterloaded sources, and other efforts to create a miniature source for improved accessibility to a variety of anatomic sites. Therefore, HDR 252Cf brachytherapy may prove to be a potential rival to the use of HDR 192Ir remotely afterloaded brachytherapy--the current standard-of-care treatment modality using HDR brachytherapy. Considering the possible improvements in clinical efficacy using HDR 252Cf brachytherapy and the enormous costs of other high-LET radiation sources, the cost differences between 252Cf and 192Ir may be well-justified.

Background: In interstitial brachytherapy (IB), cosmesis and toxicity correlate with volume of tissue irradiated, dose homogeneity index (DHI), and adjuvant doxorubicin/cyclophosphamide based chemotherapy (ACCT). MammoSite brachytherapy (MSB) irradiates smaller volumes than IB, and lower dose homogeneity does not appear to affect toxicity. However, clinical experience suggests that other factors may also play an important role in cosmesis and toxicity with MSB. We reviewed our prospectively maintained data base of women who underwent accelerated partial breast irradiation (APBI) to assess this issue., Methods: Beginning in September 1995, 115 women were enrolled in a trial evaluating APBI as monotherapy after lumpectomy. The first 75 eligible patients received IB, and the most recent 28 eligible patients received MSB. All patients received 34 gray (Gy) in 10 twice-daily fractions through high-dose rate iridium-192 brachytherapy; 19% of patients in the IB group and 0% of patients in the MSB group received ACCT., Results: At 1 year after treatment, MSB caused significantly less Grade 2-4 subcutaneous fibrosis (as graded by a radiation oncologist according to the Radiation Therapy Oncology Group/Eastern Cooperative Oncology Group system) compared with IB (10.7% vs. 32%; P = 0.04). However, when only ACCT-naïve patients in the IB group were compared with patients in the MSB group, this finding became nonsignificant. Among the patients who received MSB, significantly smaller volumes were irradiated, and the DHI was lower., Conclusions: Current studies suggest an improved toxicity profile with MSB compared with IB that is attributed to lower irradiated volumes with MSB. When only chemotherapy-naïve patients were compared, however, toxicity and cosmesis were found to be similar between MSB and IB, suggesting a more complex interplay between irradiated volumes, DHI, and chemotherapy. The relation of ACCT to toxicity in this scenario is intriguing and warrants further investigation., (Copyright 2004 American Cancer Society.)

Purpose: To determine whether intensity modulated sequential tomotherapy using the NOMOS Beak provides superior dose conformity and organ sparing to the MIMiC "1-cm" mode, and if so, to identify a subset of patients most likely to benefit from Beak intensity modulated sequential tomotherapy., Methods and Materials: Twelve patients with irregularly shaped central nervous system tumors were selected for intensity modulated radiation therapy planning. Two treatment plans, one using the Beak collimator and the other using the 1-cm MIMiC collimator, were generated for each patient with identical anatomic contouring, prescriptions, and optimization algorithms. The Beak attaches to the MIMiC collimator and truncates the 1-cm MIMiC mode beamlet size from 1.00 x 0.85 cm(2) to 1.00 x 0.39 cm(2) at isocenter. Conformity indexes were calculated for each lesion using two different prescription methodologies, and mean doses to critical structures were recorded., Results: For the first prescription methodology using uniform prescribed isodose, mean conformity index was 2.19 (range, 1.33-3.90) for the Beak compared to 2.67 (range, 1.64-4.75) for the 1-cm mode (p = 0.0003). Mean doses to the brainstem, right orbit, and left optic nerve were significantly lower with the Beak than with the 1-cm mode (p = 0.0150, 0.0068, and 0.0284, respectively). For the second prescription methodology using uniform target volume coverage prescription, mean conformity index was 2.04 (range, 1.56-2.70) for the Beak compared to 2.73 (range, 1.70-8.58) for the 1-cm mode (p = 0.07). Mean doses to the brain, brainstem, optic chiasm, right optic nerve, left optic nerve, and left orbit were significantly lower with the Beak than with the 1-cm mode (p = <0.0001, <0.0026, <0.0016, <0.0076, <0.0007, and <0.046, respectively)., Conclusion: Beak intensity modulated sequential tomotherapy is superior to the 1-cm MIMiC mode for irregularly shaped central nervous system tumors, because it provides better conformity and critical organ sparing. These differences may allow for safer dose escalation and retreatment, so the method presents an alternative to gamma knife stereotactic radiosurgery.

Purpose: The loss of expression of NES1, a novel putative tumor suppressor gene, is an early marker of breast tumorigenesis. NES1 is expressed in normal breast tissue and ductal hyperplasia but is absent or markedly diminished in invasive cancer. In cases of ductal carcinoma in situ (DCIS), NES1 expression has been shown previously to be present in approximately 50% of specimens. This study examined the expression level of NES1 in diagnostic biopsy samples found to contain pure DCIS. These data were then correlated with the pathologic findings found at definitive local surgery., Methods and Materials: Twenty-nine cases with initial biopsy showing DCIS without invasive carcinoma followed by subsequent reexcision were discovered and archived. Formalin-fixed tissue specimens were obtained for analysis. Each biopsy specimen was subjected to hematoxylin-eosin staining and reviewed by two pathologists to confirm the diagnosis of pure DCIS. NES1 cDNA (1069 bp), including 238 bp of 5' and 3' untranslated region and the entire protein-coding region, was cloned into a vector. To generate the antisense and sense RNA probes, the plasmid was linearized and the transcription reaction was carried out with polymerases T7 and T3, respectively. The detection of in situ hybridization probes was performed using an mRNAlocator-Biotin Kit. Staining was characterized as negative (0/1+) or positive (2+/3+). Subsequent to an initial biopsy diagnosis of DCIS, all cases had a definitive surgical procedure. Detailed sectioning of the resultant tissue was performed and subjected to hematoxylin-eosin staining to determine the presence or absence of invasive carcinoma., Results: The initial diagnostic biopsy specimens showed that 17 of 17 high-grade, 3 of 7 intermediate-grade, and 3 of 5 low-grade DCIS specimens were negative for NES1 expression. Of the 6 cases of DCIS found to be positive for NES1 expression, none (0%) were subsequently found to have invasive carcinoma at definitive surgery. In contrast, the loss of NES1 expression in the initial diagnostic biopsy was associated with a 40% incidence of invasive carcinoma at definitive surgery. Additional stratification by nuclear grade showed invasive carcinoma in 5 (83%) of 6 NES1-negative, low- to intermediate-grade DCIS (p

Though the 4 mm Gamma Knife helmet is used routinely, there is disagreement in the Gamma Knife users community on the value of the 4 mm helmet relative output factor. A range of relative output factors is used, and this variation may impair observations of dose response and optimization of prescribed dose. To study this variation, measurements were performed using the following radiation detectors: silicon diode, diamond detector, radiographic film, radiochromic film, and TLD cubes. To facilitate positioning of the silicon diode and diamond detector, a three-dimensional translation micrometer was used to iteratively determine the position of maximum detector response. Positioning of the films and TLDs was accomplished by manufacturing custom holders for each technique. Results from all five measurement techniques indicate that the 4 mm helmet relative output factor is 0.868 +/- 0.014. Within the experimental uncertainties, this value is in good agreement with results obtained by other investigators using diverse techniques.

Background: At 5-year follow-up, patients with Paget disease of the breast who were treated with breast-conserving surgery (BCS) and radiotherapy (RT) had excellent results. The current report provides 10- and 15-year rates of tumor control in the breast, as well as disease-free and overall survival rates following BCS and RT in a cohort of patients with Paget disease presenting without a palpable mass or mammographic density., Methods: Through a collaborative review of patients treated with BCS and RT from seven institutions, 38 cases of Paget disease of the breast presenting without a palpable mass or mammographic density were identified. All patients had pathologic confirmation of typical Paget cells at time of diagnosis. Thirty-six of 38 patients had a minimum follow-up greater than 12 months and constitute the study cohort. Ninety-four percent of patients underwent complete or partial excision of the nipple-areola complex and all patients received a median external beam irradiation dose of 50 Gy (range, 45-54 Gy) to the whole breast. Ninety-seven percent of patients also received a boost to the remaining nipple or tumor bed, a median total dose of 61.5 Gy (range, 50.4-70 Gy)., Results: With median follow-up of 113 months (range, 18-257 months), 4 of 36 patients (11%) developed a first recurrence of disease in the treated breast only. Two of the four recurrences in the breast were ductal carcinoma in situ (DCIS) only and two were invasive with DCIS. Two additional patients had a recurrence in the breast as a component of first failure. Actuarial local control rates for the breast as the only site of first recurrence were 91% at 5 years (95% confidence interval [CI], 80-100%) and 87% (95% CI, 75-99%) at both 10 and 15 years. Actuarial local control rates for breast recurrence, as a component of first failure, were 91% (95% CI, 80-100%), 83% (95% CI, 69-97%), and 76% (95% CI, 58-94%) at 5, 10, and 15 years, respectively. No clinical factors were identified as significant predictors for breast recurrence. Five-, 10- and 15-year actuarial rates for survival without disease of 97% (95% CI, 90-100%) and 5-, 10-, and 15-year actuarial rates of overall survival of 93% (95% CI, 84-100%) at 5 years and 90% (95% CI, 78-100%) at 10 and 15 years were reported., Conclusions: These data confirm excellent rates of local control, disease-free survival, and overall survival at 10 and 15 years following BCS and RT for Paget disease of the breast. This study continues to support the recommendation of local excision and definitive breast irradiation as an alternative to mastectomy in the treatment of patients with Paget disease presenting without a palpable mass or mammographic density., (Copyright 2003 American Cancer Society.DOI 10.1002/cncr.11337)

ErbB2 overexpression contributes to the evolution of a substantial group of human cancers and signifies a poor clinical prognosis. Thus, down-regulation of ErbB2 signaling has emerged as a new anti-cancer strategy. Ubiquitinylation, mediated by the Cbl family of ubiquitin ligases, has emerged as a physiological mechanism of ErbB receptor down-regulation, and this mechanism appears to contribute to ErbB2 down-regulation induced by therapeutic anti-ErbB2 antibodies. Hsp90 inhibitory ansamycin antibiotics such as geldanamycin (GA) induce rapid ubiquitinylation and down-regulation of ErbB2. However, the ubiquitin ligase(s) involved has not been identified. Here, we show that ErbB2 serves as an in vitro substrate for the Hsp70/Hsp90-associated U-box ubiquitin ligase CHIP. Overexpression of wild type CHIP, but not its U-box mutant H260Q, induced ubiquitinylation and reduction in both cell surface and total levels of ectopically expressed or endogenous ErbB2 in vivo, and this effect was additive with that of 17-allylamino-geldanamycin (17-AAG). The CHIP U-box mutant H260Q reduced 17-AAG-induced ErbB2 ubiquitinylation. Wild type ErbB2 and a mutant incapable of association with Cbl (ErbB2 Y1112F) were equally sensitive to CHIP and 17-AAG, implying that Cbl does not play a major role in geldanamycin-induced ErbB2 down-regulation. Both endogenous and ectopically expressed CHIP and ErbB2 coimmunoprecipitated with each other, and this association was enhanced by 17-AAG. Notably, CHIP H260Q induced a dramatic elevation of ErbB2 association with Hsp70 and prevented the 17-AAG-induced dissociation of Hsp90. Our results demonstrate that ErbB2 is a target of CHIP ubiquitin ligase activity and suggest a role for CHIP E3 activity in controlling both the association of Hsp70/Hsp90 chaperones with ErbB2 and the down-regulation of ErbB2 induced by inhibitors of Hsp90.

Logistical barriers of time and travel created by the conventional six-week course of radiotherapy prevent many women from pursuing breast conservation treatment. For the past 12 years, Accelerated Partial Breast Irradiation (APBI) has been investigated as a potential alternative treatment approach in women with early stage breast cancer. The ability to complete treatment in five days has the potential to provide additional women with the option of breast conservation. The validity of this APBI is supported in the study of in-breast recurrence patterns, pathologic data and the clinical treatment experience. The review of the recent data on contemporary APBI reveals that patient selection criteria and brachytherapy quality assurance are clearly critical components and necessary to assure a successful treatment outcome. This updated report from the American Brachytherapy Society on Accelerated Partial Breast Irradiation reviews the appropriate background data supporting this treatment approach with conclusions regarding patient selection criteria and treatment delivery.

We have recently identified E6TP1 (E6-targeted protein 1) as a novel high-risk human papillomavirus type 16 (HPV16) E6-binding protein. Importantly, mutational analysis of E6 revealed a strong correlation between the transforming activity and its abilities to bind and target E6TP1 for ubiquitin-mediated degradation. As a region within E6TP1 has high homology with GAP domains of known and putative Rap GTPase-activating proteins (GAPs), these results raised the possibility that HPV E6 may alter the Rap small-G-protein signaling pathway. Using two different approaches, we now demonstrate that human E6TP1 exhibits GAP activity for Rap1 and Rap2, confirming recent findings that a closely related rat homologue exhibits Rap-specific GAP activity. Using mutational analysis, we localize the GAP activity to residues 240 to 945 of E6TP1. Significantly, we demonstrate that coexpression of HPV16 E6, by promoting the degradation of E6TP1, enhances the GTP loading of Rap. These results support a role of Rap small-G-protein pathway in E6-mediated oncogenesis.

Background: A prospectively applied treatment policy for breast-conserving therapy used margin assessment as the exclusive guide to the intensity of radiation therapy directed at the tumor bed., Methods: From 1982 to 1994, 498 women with 509 Stage I/II breast carcinomas with a median follow-up of 121 months were treated. Final margin status (FMS) categories were defined as greater than 5 mm, greater than 2-5 mm, greater than 0-2 mm, and positive. For margins less than or equal to 2 mm or indeterminate, reexcisions were performed if feasible. All patients received whole breast irradiation to 50.0-50.4 Gy. Final tumor bed boosts as a function of FMS were as follows: no residual on reexcision, no boost performed; FMS greater than 5 mm, boost of 10 Gy; FMS greater than 2-5 mm, boost of 14 Gy; FMS greater than 0-2 mm or positive, boost of 20 Gy. Cases were analyzed for local failure with respect to histology, age, tumor size, excision volume, reexcision, and total dose., Results: FMS was positive, greater than 0-2 mm, greater than 2-5 mm, and greater than 5 mm, and no residual tumor on reexcision in 21%, 20%, 17%, 14%, and 28% of cases, respectively. At 12 years, Kaplan-Meier local failure rates were 17% for FMS positive, 9% for FMS greater than 0-2 mm, 5% for FMS greater than 2-5 mm, 0% for FMS greater than 5 mm, and 6% for specimens without evidence of residuum on reexcision (P = 0.009). Patients 45 years old and younger had a 12-year local failure rate of 15% whereas patients older than 45 years had a 12-year local failure rate of 6% (P = 0.01). On multivariate analysis, young age (P = 0.03) predicted increased local failure rate, whereas margins that were less than or equal to 2 mm or positive predicted late (> 5 years) but not early (< or = 5 years) recurrence (P = 0.003)., Conclusions: Graded tumor bed dose escalation in response to FMS results in very low rates of local failure over the first 5 years for all FMS categories. However, tumors with close/positive margins have significantly increased local failure rates after 5 years of follow-up even with increased radiation boost dose. In addition, graded tumor bed dose escalation does not fully overcome the adverse influence of young age., (Copyright 2003 American Cancer Society.DOI 10.1002/cncr.10981)

Understanding the molecular and genetic events affecting breast cancer development not only helps oncologists address important questions commonly asked by their patients but also helps clinicians gain insights into the biology of the disease. Although the molecular and genetic determinants of most sporadic breast cancer remain unknown, significant advances in the understanding of events that contribute to breast cancer formation have been made. It is now recognized that mutations in some tumor suppressor genes, such as p53, BRCA1, BRCA2, PTEN, or ATM, or epigenetic functional inactivation of other tumor suppressor genes, such as SYK and NES1, appear to play important early roles in the formation of some breast cancers. In addition, alterations in proto-oncogenes, such as HER2/neu, may contribute to the development of some breast cancer. The goal of this article is to further introduce clinicians to molecular and genetic pathways that contribute to breast cancer formation. By participating in the study of breast cancer development at the molecular as well as the histopathological level, oncologists can help develop novel prevention, diagnostic, and therapeutic approaches for the future., (Copyright 2002, Elsevier Science (USA).)

The vast majority of breast cancers are carcinomas that arise from mammary epithelial cells (MECs). One of the key early events in tumorigenic transformation is the ability of cells to overcome replicative senescence. However, the precise genetic changes that are responsible for this event in MECs is largely unknown. Here, we report that Bmi-1, originally identified as a c-Myc cooperating oncoprotein, can bypass senescence, extend the replicative life span, and immortalize MECs. Furthermore, Bmi-1 was overexpressed in immortal MECs and several breast cancer cell lines. Overexpression of Bmi-1 in MECs led to activation of human telomerase reverse transcriptase (hTERT) transcription and induction of telomerase activity. Telomerase induction by Bmi-1 was an early event in the extension of the replicative life span and immortalization. Bmi-1 was not overexpressed in hTERT-immortalized MECs, suggesting that Bmi-1 functions upstream of hTERT. Although, c-Myc has been reported to induce telomerase in MECs, Bmi-1 appeared to act independently of c-Myc binding sequences in the hTERT promoter. Deletion analysis of the Bmi-1 protein suggested that the RING finger, as well as a conserved helix-turn-helix-turn domain, were required for its ability to induce telomerase and immortalize MECs. These data suggest that Bmi-1 regulates telomerase expression in MECs and plays a role in the development of human breast cancer.

High-risk human papillomaviruses (HPVs) are associated with carcinomas of the cervix and other genital tumors. The HPV oncoprotein E6 is essential for oncogenic transformation. We identify here hADA3, human homologue of the yeast transcriptional coactivator yADA3, as a novel E6-interacting protein and a target of E6-induced degradation. hADA3 binds selectively to the high-risk HPV E6 proteins and only to immortalization-competent E6 mutants. hADA3 functions as a coactivator for p53-mediated transactivation by stabilizing p53 protein. Notably, three immortalizing E6 mutants that do not induce direct p53 degradation but do interact with hADA3 induced the abrogation of p53-mediated transactivation and G(1) cell cycle arrest after DNA damage, comparable to wild-type E6. These findings reveal a novel strategy of HPV E6-induced loss of p53 function that is independent of direct p53 degradation. Given the likely role of the evolutionarily conserved hADA3 in multiple coactivator complexes, inactivation of its function may allow E6 to perturb numerous cellular pathways during HPV oncogenesis.

Purpose: To evaluate the clinical feasibility of daily computer-assisted transabdominal ultrasonography for target position verification in the setting of intensity-modulated radiotherapy (IMRT) for prostate cancer., Methods and Materials: Twenty-three patients with clinically localized prostate cancer were treated using a sequential tomotherapy IMRT technique (Peacock) and daily computer-assisted transabdominal ultrasonography (BAT) for target localization. Patients were instructed to maintain a full bladder and were placed in the supine position using triangulation tattoos and a leg immobilizer to minimize pelvic rotation. The BAT ultrasound system is docked to the treatment collimator and electronically imports the CT simulation target contours and isocenter. The system is able to use the machine isocenter as a reference point to overlay the corresponding CT contours onto the ultrasound images captured in the transverse and sagittal planes. A touch screen menu is used to maneuver the CT contours in three dimensions such that they match the ultrasound images. The system then displays the three-dimensional couch shifts required to produce field alignment. Data were prospectively collected to measure the frequency by which useful ultrasound images were obtained, the amount of time required for localization/setup, and the direction/magnitude of the positional adjustments., Results: Of the 23 patients, the BAT ultrasound system produced images of sufficient quality to perform the overlay of the CT contours in 19 patients such that positional verification could be reliably performed. Poor image quality was associated with patient inability to maintain a full bladder, large body habitus, or other anatomic constraints. Of the 19 assessable patients, a total of 185 treatment alignments were performed (mean 8.8/patient). For all cases, the average time required for the daily ultrasound imaging and positional adjustments was 11.9 min. After the initial 5 cases, the user experience skills improved such that the time required for image verification/positional adjustments decreased to a mean of 5.6 min. The average right-left, AP, and cranial-caudal adjustment was 2.6 +/- 2.1 mm, 4.7 +/- 2.7 mm, and 4.2 +/- 2.8 mm, respectively. Positional adjustments >10 mm were infrequent and related primarily to misidentification of the target structures on the ultrasound image, patient movement, or improper registration of the triangulation tattoos., Conclusion: Daily computer-assisted BAT ultrasound positional verification of the prostate can be successfully performed through the acquisition of high-quality images in most patients with only a modest increase in treatment setup time. Positional data obtained with this system resulted in clinically meaningful adjustments in daily setup for sequential IMRT that would not be otherwise apparent from other verification modalities.

Purpose: To investigate the feasibility, toxicity, cosmetic outcome, and local control of high-dose-rate (HDR) brachytherapy alone without whole breast external beam irradiation for early-stage breast carcinoma., Methods and Materials: Between June 1997 and August 1999, 32 women diagnosed with a total of 33 AJCC Stage I/II breast carcinomas underwent surgical breast excision and postoperative irradiation using HDR brachytherapy interstitial implantation as part of a multi-institutional clinical Phase I/II protocol. Eligible patients included those with T1, T2, N0, N1 (< or =3 nodes positive), and M0 tumors of nonlobular histologic features with negative surgical margins, no extracapsular lymph node extension, and a negative postexcision mammogram. Brachytherapy catheters were placed at the initial excision, reexcision, or either sentinel or full-axillary sampling. Direct visualization, surgical clips, and ultrasound and/or CT scan assisted in the delineation of the target volume, defined as the excision cavity plus a 2-cm margin. High-activity 192Ir (3-10 Ci) was used to deliver 340 cGy/fraction, 2 fractions/d, for 5 consecutive days, to a total dose of 34 Gy to the target volume. Source position and dwell times were calculated using standard volume optimization techniques., Results: The median follow-up of all patients was 33 months, and the mean patient age was 63 years. The mean tumor size was 1.3 cm, and 55% had an extensive intraductal component. Three patients had positive axillary nodes. Two patients experienced moderate perioperative pain that required narcotic analgesics. No peri- or postoperative infections occurred. No wound healing problems and no significant skin reactions related to the implant developed. The Radiation Therapy Oncology Group late radiation morbidity scoring scheme was applied to the entire 33-case cohort. In the assessment of the skin, 30 cases were Grade 0-1 and 3 cases were Grade 2. Subcutaneous toxicity was scored as 11 patients with Grade 0, 3 with Grade 1, 8 with Grade 2, 3 with Grade 3, and 8 with Grade 4. Clinically evident fat necrosis occurred in 8 patients at a median of 7.5 months after HDR brachytherapy completion. The only variables significantly associated with Grade 3-4 toxicity were the number of source dwell positions and the volume of tissue encompassed by the prescription isodose shell. The global cosmetic scores after a minimum of 18 months' follow-up were 0 cases with poor, 4 with fair, 5 with good, and 24 with excellent scores. One case of ipsilateral breast tumor recurrence was diagnosed 23 months after HDR brachytherapy, for a 4-year actuarial recurrence rate of 3%. This failure appeared to be a new primary tumor, because it was histologically distinct from the initial tumor and was located 9 cm from the initial tumor bed and 3 cm from the edge of the implant volume., Conclusion: Radiotherapy of the tumor bed alone with HDR interstitial brachytherapy is associated with a 33% incidence of Grade 3-4 s.c. toxicity, but with generally favorable overall cosmetic results. The risk of toxicity appears to be primarily related to the implant volume. With limited follow-up, the incidence of ipsilateral breast tumor recurrence was low.

High-risk human papilloma viruses are known to be associated with cervical cancers. We have reported previously that the high-risk human papillomavirus (HPV) E6 oncoprotein interacts with E6TP1, a novel Rap GTPase-activating protein (RapGAP). Similar to p53 tumor suppressor protein, the high-risk HPV E6 oncoproteins target E6TP1 for degradation. The HPV16 E6-induced degradation of E6TP1 strongly correlates with its ability to immortalize human mammary epithelial cells. In this study, we used treatment with a proteasome inhibitor MG132, analysis in CHO-ts20 cells with a thermolabile ubiquitin-activating enzyme, and direct detection of ubiquitin-modified E6TP1 to demonstrate that E6TP1 is targeted for degradation by the ubiquitin-proteasome pathway both in the presence and in the absence of E6. Using deletion mutants of E6TP1, we mapped the region required and sufficient for E6 binding to COOH-terminal 40 amino acid residues and showed this region to be necessary for E6-dependent degradation of E6TP1. Furthermore, the E6-binding region of E6TP1 complexes with E6AP via E6. Importantly, the purified E6AP enhanced the ubiquitination and degradation of E6TP1 in the presence of E6 in vitro. Additionally, the expression of a dominant-negative E6AP mutant (C833A) in cells inhibited the E6-induced degradation of E6TP1. These findings demonstrate that the E6-induced decrease in the levels of E6TP1 protein involves the E6AP-mediated ubiquitination followed by proteasome-dependent degradation.

Background: Margin width is considered the most important risk factor for local recurrence in ductal carcinoma in situ (DCIS) of the breast. The purpose of this report is to assess the predictive utility of lumpectomy specimen margin assessment for the presence and extent of residual DCIS., Methods: Specimens from 253 DCIS cases with lumpectomy and reexcision were studied to determine to the probability of residual DCIS on reexcision. The probability of residual tumor was evaluated with respect to tumor size, margin status, nuclear grade, presence of necrosis, patient age, and the extent of specimen processing (number of sections/volume tissue). Lesions were grouped by size: less than or equal to 2 mm, greater than 2-15 mm, greater than 15-40 mm, or greater than 40 mm. Margin width was recorded as the distance of DCIS to the closest specimen edge or, for positive margins, scored as: extensive (margin involvement in > or =8 sections or >4 low-power fields [LPFs]), moderate (5-7 sections or 2-4 LPFs), minimal (2-4 sections or 1 LPF), or focal (1 section, single focus). The amount of residual tumor was graded by maximum dimension on a semiquantitative basis., Results: Initial excision margin significantly predicted for the presence of residual tumor on reexcision. Residual tumor was found on reexcision in 85% of extensively positive, 68% of moderately positive, 46% of minimally positive, 30% of focally positive, 41% of greater than 0-1 mm, 31% of greater than 1-2 mm, and 0% of greater than 2 mm margins (P < 0.0001). On univariate analysis, margin width and lesion size of initial excision specimens significantly predicted for the presence of residual DCIS on reexcision. Age, grade, necrosis, and extent of specimen processing were not significant prognostic factors. On multivariate analysis, both initial margin width (P < 0.0001) and lesion size (P = 0.02) significantly predicted for residual DCIS. As for amount of residual tumor, margin width and initial lesion dimension both significantly predicted for medium to large residuum, whereas age 45 years or younger was of borderline significance on univariate analysis. On multivariate analysis, margin width and lesion size on initial excision both remained significant predictors of larger volume residual tumor., Conclusions: The margin status of a DCIS lumpectomy specimen is the most important predictive factor for both the presence and amount of residual disease., (Copyright 2002 American Cancer Society.)

Logistical barriers of time and travel created by the conventional six week course of radiotherapy prevent many women from pursuing breast conservation treatment. For the past 12 years, Accelerated Partial Breast Irradiation (APBI) has been investigated as a potential alternative treatment approach in women with early stage breast cancer. The ability to complete treatment in five days has the potential to provide additional women with the option of breast conservation. The validity of this APBI is supported in the study of in-breast recurrence patterns, pathologic data and the clinical treatment experience. The review of the recent data on contemporary APBI reveals that patient selection criteria and brachytherapy quality assurance are clearly critical components and necessary to assure a successful treatment outcome. This updated report from the American Brachytherapy Society on Accelerated Partial Breast Irradiation reviews the appropriate background data supporting this treatment approach with conclusions regarding patient selection criteria and treatment delivery.

The normal epithelial cell-specific-1 (NES1)/kallikrein 10 gene is expressed in normal mammary epithelial cells, but its expression is dramatically decreased in breast cancer cell lines. Now, we have cloned and characterized the active promoter region of NES1. Using a luciferase reporter system, we demonstrate that most tumor cell lines are able to support full or partial transcription from the NES1 promoter, suggesting a role for promoter-independent cis-acting mechanisms of loss of NES1 expression. We show that hypermethylation of the NES1 gene represents one such mechanism. Using methylation-specific PCR and sequence analysis of sodium bisulfite-treated genomic DNA, we demonstrate a strong correlation between exon 3 hypermethylation and loss of NES1 mRNA expression in a panel of breast cancer cell lines and in primary tumors. Treatment of NES1-nonexpressing cells with a demethylating agent led to reexpression of NES1, suggesting an important role of hypermethylation in the loss of NES1 expression. We suggest that hypermethylation is responsible for tumor-specific loss of NES1 gene expression. Our results also suggest that hypermethylation of the NES1 gene may serve as a potential marker for breast cancer.

Purpose: Normal epithelial cell specific-1 (NES1)/kallikrein 10 gene is expressed in normal mammary and prostate epithelial cells, but the expression of NES1 mRNA and protein is markedly reduced in established breast and prostate cancer cell lines although the NES1 gene is intact. Here, we wished to assess whether NES1 expression is down-regulated in primary breast cancers., Experimental Design: We developed and used an in situ hybridization technique with an antisense NES1 probe to detect NES1 mRNA in sections of normal breast specimens, typical and atypical ductal hyperplasia, ductal carcinoma in situ, and infiltrating ductal carcinoma., Results: All of the 30 normal breast specimens showed high NES1 expression. Notably, 18 (75%) of 24 typical and atypical breast hyperplasia specimens showed high NES1 expression, with weak-to-moderate expression in 6 (25%). Significantly, 13 (46%) of 28 ductal carcinoma in situ specimens lacked NES1 expression, and the remaining 15 (54%) showed weak-to-moderate expression. Finally, 29 of 30 (97%) infiltrating ductal carcinoma grades I-III samples lacked NES1 mRNA, with weak expression in the remaining one sample., Conclusions: Our results demonstrate that NES1 mRNA is expressed in normal breast tissue and benign lesions, with loss of NES1 expression during tumor progression. We suggest that NES1 expression may serve as a molecular tool in the study of breast cancer progression. Studies with larger series of specimens should help assess whether NES1 expression can be a diagnostic and/or prognostic marker in breast and other cancers.

Purpose: To investigate the incidence of and variables associated with clinically evident fat necrosis in women treated on a protocol of high-dose-rate (HDR) brachytherapy alone without external-beam whole-breast irradiation for early-stage breast carcinoma., Methods and Materials: From 6/1997 until 8/1999, 30 women diagnosed with Stage I or II breast carcinoma underwent surgical excision and postoperative irradiation via HDR brachytherapy implant as part of a multi-institutional clinical Phase I/II protocol. Patients eligible included those with T1, T2, N0, N1 (< or = 3 nodes positive), M0 tumors of nonlobular histology with negative surgical margins, no extracapsular lymph-node extension, and a negative postexcision mammogram. Brachytherapy catheters were placed at the initial excision, re-excision, or at the time of axillary sampling. Direct visualization, surgical clips, ultrasound, or CT scans assisted in delineating the target volume defined as the excision cavity plus 2-cm margin. High activity (192)Ir (3-10 Ci) was used to deliver 340 cGy per fraction, 2 fractions per day, for 5 consecutive days to a total dose of 34 Gy to the target volume. Source position and dwell times were calculated using standard volume optimization techniques. Dosimetric analyses were performed with three-dimensional postimplant dose and volume reconstructions. The median follow-up of all patients was 24 months (range, 12-36 months)., Results: Eight patients (crude incidence of 27%) developed clinically evident fat necrosis postimplant in the treated breast. Fat necrosis was determined by clinical presentation including pain and swelling in the treated volume, computed tomography, and/or biopsy. All symptomatic patients (7 of 8 cases) were successfully treated with 3 to 12 months of conservative management. Continuous variables that were found to be associated significantly with fat necrosis included the number of source dwell positions (p = 0.04), and the volume of tissue which received fractional doses of 340 cGy, 510 cGy, and 680 cGy (p = 0.03, p = 0.01, and p = 0.01, respectively). Other continuous variables including patient age, total excised tissue volume, tumor size, number of catheters, number of days the catheters were in place, planar separation, dose homogeneity index (DHI), and uniformity index (UI) were not significant. Discrete variables including the presence/absence of DCIS, sentinel versus full axillary nodal assessment, receptor status, presence/absence of diabetes, and the use of chemotherapy or hormone therapy were not found to have a significant association with the risk of fat necrosis., Conclusions: In this study of HDR brachytherapy of the breast tumor excision cavity plus margin, treatment was planned and delivered in accordance with the dosimetric parameters of the protocol resulting in a high degree of target volume dose homogeneity. Nonetheless, at a median follow-up of 24 months, a high rate of clinically definable fat necrosis occurred. The overall implant volume as reflected in the number of source dwell positions and the volume of breast tissue receiving fractional doses of 340, 510, and 680 cGy were significantly associated with fat necrosis. Future dosimetric optimization algorithms for HDR breast brachytherapy will need to include these factors to minimize the risk of fat necrosis.

Recent analyses have identified a number of binding partners for E6, including E6AP, ERC55, paxillin, hDlg, p300, interferon regulatory factor 3, hMCM7, Bak, and E6TP1. Notably, association with E6 targets p53, E6TP1, myc, hMCM7, and Bak for degradation. However, the relative importance of the various E6 targets in cellular transformation remains unclear. E6 alone can dominantly immortalize normal human mammary epithelial cells (MECs), permitting an assessment of the importance of various E6 targets in cellular transformation. Studies in this system indicate that E6-induced degradation of p53 and E6 binding to ERC55 or hDlg do not correlate with efficient immortalization. Here, we have examined the role of E6TP1, a Rap GTPase-activating protein, in E6-induced immortalization of MECs. We tested a large set of human papillomavirus type 16 E6 mutants for their ability to bind and target E6TP1 for degradation in vitro and in vivo. We observed a strict correlation between the ability of E6 protein to target E6TP1 for degradation and its ability to immortalize MECs. Recent studies have identified telomerase as a target of E6 protein. Previous analyses of E6 mutants have revealed this trait to closely correlate with MEC immortalization. We examined our entire panel of E6 mutants for rapid induction of telomerase activity and found in general a strong correlation with immortalizing ability. The tight correlation between E6TP1 degradation and MEC immortalization strongly supports a critical role of functional inactivation of E6TP1 in E6-induced cellular immortalization.

Purpose: RTOG protocol 90-05 determined the maximum acutely tolerated dose of single-fraction radiosurgery in patients receiving prior fractionated large volume cranial irradiation. Data from 90-05 have suggested that patients treated with a gamma unit, compared to linac-based therapy, have a tumor control advantage and lower rates of severe complications. This study was performed to investigate the radiobiologic effect of using one vs. two isocenters in single-fraction radiosurgery of ellipsoidal targets., Methods and Materials: For a series of ellipsoidal targets that varied by volume and radiosensitivity, single and two-isocenter treatment plans were generated to approximate those typically employed for gamma unit and linac radiosurgery. Tumor control probabilities (TCP) and normal tissue complication probabilities (NTCP) were generated automatically by the treatment planning system based on established parameter values., Results: The modeling data showed that multiple-isocenter plans resulted in improved TCP with equivalent or lesser NTCP, particularly for larger, radioresistant targets. Multiple-isocenter plans reduce the amount of normal tissue that receives high dose. Also, areas within the tumor receive significantly higher doses than the prescription dose, which contributes to increased tumor cell inactivation., Conclusion: For ellipsoidal targets, radiobiologic modeling data are consistent with the clinical findings of the RTOG 90-05 trial, as they predict improved outcome with a multiple-isocenter plan relative to a single-isocenter plan. The benefit is most apparent with increasing target volume and decreasing tumor radiosensitivity.

In order to assess the utility of margin width in relation to other histopathologic features as a determinant of local control in ductal carcinoma in situ (DCIS) of the breast, we retrospectively examined the treatment of 109 breasts treated with (n = 54) or without adjuvant radiotherapy (n = 55). Median follow-up was 49 and 54 months for patients treated with excision alone (E) or excision plus adjuvant radiotherapy (E+XRT), respectively. Cases treated with E+XRT were significantly larger and had a trend towards closer surgical margins than those treated with E alone. For all cases, margin width < or = 1 mm and lesion diameter >15 mm were significantly associated with increased local recurrence. Lesion size < or = 15 mm was associated with no cases of local failure regardless of treatment arm. For lesions >15 mm in diameter, there was a significant decrease in 5-year local failure with E+XRT compared to E alone (21% vs. 36%, P = 0.03). Tumor margin >1 mm was associated with a low rate of 5-year local failure for either E alone or E+XRT (10.9% vs. 4.6%, P = NS). Tumor margin < = 1 mm had a high rate of local failure that was not significantly decreased by the addition of adjuvant radiotherapy. These results show that large diameter (>15 mm) and close surgical margins (< or = 1 mm) are the dominant risk factors for local recurrence in DCIS. E+XRT significantly decreased local failure risk compared to E alone for large lesions but not for those with close margins., (Copyright 2002 Wiley-Liss, Inc.)

Multiple Genetic Changes Are Required for Efficient Immortalization of Different Subtypes of Normal Human Mammary Epithelial Cells. Breast cancer is the second leading cause of cancer-related deaths of women in the U.S. About 180,000 new cases of breast cancer are diagnosed each year, a quarter of them fatal. Early detection is the key to the survival of these patients. However, there are no molecular markers to detect breast cancer at very early stages. A hurdle in understanding the early molecular changes in breast cancer has been the difficulty in establishing premalignant lesions and primary breast tumors as in vitro cell cultures. Normal epithelial cells grow for a finite life span and then senesce. Immortalization is defined by continuous growth of otherwise senescing cells and is believed to represent an early stage in tumor progression. To examine these early stages, we and others have developed in vitro models of mammary epithelial cell immortalization. These models have been extremely important in understanding the role of various tumor suppressor pathways that maintain the normal phenotypes of mammary epithelial cells. In this paper, we describe the establishment of these models and their relevance to understanding the molecular changes that occur in early breast cancer. These models have helped to identify molecular changes that occur in early breast cancers and appear to be well suited to identify novel markers for early diagnosis of breast cancer.

Breast conservation therapy consisting of tumor excision followed by whole breast irradiation is an accepted alternative to mastectomy for many women with early invasive breast cancer. Ongoing research questions include defining the role of the tumor bed irradiation boost, the identification of patients who are at sufficiently low risk of breast cancer recurrence to be treated with excision only, exploring tumor bed brachytherapy as an alternative to whole breast irradiation, and biologic considerations in the future local management of breast cancer.

The high risk human papillomaviruses (HPVs) are associated with carcinomas of cervix and other genital tumors. Previous studies have identified two viral oncoproteins E6 and E7, which are expressed in the majority of HPV-associated carcinomas. The ability of high risk HPV E6 protein to immortalize human mammary epithelial cells has provided a single gene model to study the mechanisms of E6-induced oncogenic transformation. In recent years, it has become clear that in addition to E6-induced degradation of p53 tumor suppressor protein, other targets of E6 are required for mammary epithelial cells immortalization. Using the yeast two-hybrid system, we have identified a novel interaction of HPV16 E6 with protein kinase PKN, a fatty acid- and Rho small G protein-activated serine/threonine kinase with a catalytic domain highly homologous to protein kinase C. We demonstrate direct binding of high risk HPV E6 proteins to PKN in wheat-germ lysate in vitro and in 293T cells in vivo. Importantly, E6 proteins of high risk HPVs but not low risk HPVs were able to bind PKN. Furthermore, all the immortalization-competent and many immortalization-non-competent E6 mutants bind PKN. These data suggest that binding to PKN may be required but not sufficient for immortalizing normal mammary epithelial cells. Finally, we show that PKN phosphorylates E6, demonstrating for the first time that HPV E6 is a phosphoprotein. Our finding suggests a novel link between HPV E6 mediated oncogenesis and regulation of a well known phosphorylation cascade.

Purpose: To determine, on the basis of radiobiological models, optimal modalities of radiotherapy for localized prostate cancer, and to provide a rational basis for therapeutic decisions., Methods and Materials: An algorithm based on extensions to the linear-quadratic (LQ) cell survival model is constructed for fractionated and protracted irradiation. These radiobiological models include prostate tumor cell line-derived LQ parameters, clonogen repopulation, repair of sublethal damage, hypoxia, and radioisotope decay. In addition, dose inhomogeneities for both IMRT and brachytherapy (125I and 103Pd) from patient-derived Dose Volume Histograms (DVH), as well as dose escalation, are incorporated. Three risk groups are defined in terms of sets of biologic parameters tailored to correspond to clinical risk groups as follows: Favorable-iPSA <10 and bGS < or =6 and stage T2; Intermediate-one parameter increased; and Unfavorable-two or more parameters increased. Tumor control probabilities (TCP) are predicted for conventional external beam radiotherapy (EBRT, including 3D-CRT), intensity modulated radiotherapy (IMRT), and permanent brachytherapy., Results: Brachytherapy is less susceptible to variations in alpha/beta than EBRT and more susceptible to variations in clonogen potential doubling time (Tp). Our models predict TCP consistent with the bNED results from recent dose escalation trials and long-term outcomes from brachytherapy. TCP from IMRT are systematically superior to those from conventional fractionated RT, and suggests its possible use in dose escalation without additional dose to surrounding normal tissues. For potentially rapidly dividing tumors (Tp < 30 days) 103Pd yields superior cell kill compared with 125I, but for very slowly proliferating tumors the converse is suggested. Brachytherapy predicts equivalent or superior TCP to dose escalated EBRT. For unfavorable risk tumors, combined 45 Gy EBRT+brachytherapy boost predicts superior TCP than with either modality alone., Conclusions: The radiobiological models presented suggest a rational basis for choosing among several radiotherapeutic modalities based on biologic risk factors. In addition, they suggest that IMRT may potentially be superior to 3D-CRT in allowing dose escalation without increased morbidity, and that brachytherapy, as monotherapy or as boost, may achieve superior tumor control compared with dose escalation 3D-CRT. The latter conclusion is supported by clinical data.

Purpose: Young age and extensive intraductal component (EIC) histology have been shown to be associated with increased local recurrence in women treated with breast conservation therapy. This study was conducted to determine if the status of the lumpectomy specimen margin consistently predicted for residual tumor burden risk irrespective of these variables., Methods and Materials: As part of an institutional prospective approach for breast conservation therapy (BCT), 265 cases with AJCC Stage I/II carcinoma with an initial excision margin that was < or =2 mm or indeterminate were subjected to reexcision. The probability of residual tumor (+RE) was evaluated with respect to tumor size, histopathologic subtype (invasive ductal carcinoma, invasive ductal carcinoma with an EIC, and invasive lobular carcinoma), relative closeness of the measured margin, and the extent of margin positivity graded as focal, minimal, moderate, or extensive. The amount of residual tumor was graded as microscopic, small, medium, or large. All variables were analyzed for patient age < or =45 or >45 years., Results: There was no significant difference in the incidence of a +RE according to age < or =45 versus >45 years when the margin was >0 < or =2 mm. Of the patients aged < or =45 years, the incidence of a +RE with a margin that was positive as compared to >0 < or =2 mm was 71% vs. 23%, respectively (p = 0.002). For women >45 years old, the difference in the incidence of +RE comparing margins that were positive or >0 < or =2 mm was not significant at 50% vs. 40%, respectively (p = 0.23). For all cases in aggregate, age < or =45 years was associated with a greater incidence of +RE as compared to patients aged >45 years with the discrepant incidence of a +RE by age strata most pronounced for focally positive margins (60% vs. 18%;p< or =0.05). In a logistic regression analysis, age (per year, as a continuous variable) and an EIC histology were significantly associated with the probability of a +RE (odds ratio [OR] = 0.80, p = 0.05 and OR = 1.9, p = 0.01, respectively). Tumor size was not significant (p = 0.23). In patients with an EIC histology, margin status is generally less predictive for differences in the incidence of a +RE. Further, the overall magnitude of difference in the incidence of a +RE related to age appears to be minimized when an EIC histology is present. In contrast, for cases classified as having non-EIC histology, there is a near-linear relationship for both age strata with respect to margin status and the incidence of a +RE. When histology is classified as non-EIC, age < or =45 years is consistently associated with a greater risk of residual tumor for all margin status categories. When the extent of margin positivity was graded as focal or minimal, residual tumor was semiquantitatively estimated as a medium/large amount in 33% versus 26% of cases aged < or =45 or >45 years, respectively (p = 0.62)., Conclusion: For positive lumpectomy specimen margins, younger age is associated with an increased residual tumor risk. An EIC histology appears to be associated with an elevated risk of residual tumor irrespective of age and may undermine the predictive utility of margin status. Therefore, age and an EIC histology should be factored into risk assessments for residual tumor that rely upon margin assessment.

Purpose: To study factors related to breast cosmetic outcome in patients treated with an interstitial implant as part of breast-conservation therapy., Materials and Methods: One hundred fifty-six patients with stage I or II breast carcinoma who received 50 Gy of external-beam irradiation followed by a 20-Gy interstitial boost were examined. The dose homogeneity index (DHI) was calculated for each evaluable implant and was examined in light of other patient-, treatment-, and tumor-related variables previously demonstrated to affect cosmesis., Results: Of the variables examined, both the DHI (P = .021) and the total excision volume (P = .019) were significantly related to cosmetic outcome (excellent vs less than excellent) in a univariate model. In the multivariate analysis, only the total excision volume remained significant (P = .032). The mean total excision volume +/- SD in patients with excellent cosmetic outcome (81.8 cm3 +/- 84.0) was significantly less than that in patients with less than excellent cosmetic outcome (120 cm3 +/- 84). The probability of excellent cosmetic outcome linearly increased with an increase in DHI. The mean DHI was 0.74 +/- 0.12 for the cases with excellent cosmetic outcome and 0.68 +/- 0.10 for those with less than excellent cosmetic outcome., Conclusion: To achieve optimal cosmesis, DHI should be maximized. The volume of tissue removed, however, remains the most significant determinant.

Purpose: To assess the effect of local-regional radiotherapy (RT) on the outcome of breast cancer patients with > or = 10 positive axillary lymph nodes who have received modern conventional or high-dose systemic therapy., Methods and Materials: A total of 55 women with local-regionally confined breast cancer involving 10 or more axillary nodes were treated between October 1983 and January 1996. Local-regional therapy consisted of modified radical mastectomy in 39 and breast-conserving surgery in 16. Postoperative radiotherapy was given to 44 of the 55 patients. Radiotherapy consisted of tangential fields to the chest wall or intact breast to a median dose of 50.40 Gy. A total of 86% (38 of 44) received regional nodal irradiation as follows: 35 patients received RT to the supraclavicular (SC) region and axillary midplane to a median dose of 50.40 Gy and 46.20 Gy, respectively; 3 patients received RT to the SC region without inclusion of the axilla to a median dose of 50. 40 Gy. All patients received adjuvant standard-dose systemic chemotherapy, 9 of whom received additional intensification chemotherapy followed by autologous bone-marrow transplant (ABMT) or peripheral blood stem-cell transplant (PBSC). Twenty-five patients received adjuvant tamoxifen., Results: With a median follow-up of 30 months, the crude overall survival (OS) and disease-free survival (DFS) for the entire group were 67% and 53%, respectively. On univariate analysis of various clinical, pathological, and therapy-related features, radiotherapy emerged as the most important factor influencing the relapse rate. The addition of RT was significantly associated with an improved DFS (p = 0.003), specifically by prolonging the time to disease progression. The median time to failure was 61 months and 12.5 months with and without RT, respectively. Patients receiving RT also appeared to survive longer; however, the groups were not statistically different (p = 0.10). Analysis of the patterns of failure showed local-regional recurrence (LRR) as the first site of failure in 12 (22%) of 55 and distant failure in 20 (36%) of 55. Univariate results revealed both radiotherapy and tamoxifen to be significantly associated with decreased LRR rates (p = 0.0001 and p = 0.03, respectively); only RT remained independently significant on multivariate analysis., Conclusion: Local-regional radiotherapy is an essential component of the management of breast cancer patients with extensive nodal involvement, despite the use of contemporary adjuvant chemotherapy including high-dose regimens with autologous rescue. In addition to the expected improvement in LRR, radiotherapy is also associated with significantly prolonged DFS and a trend for improvement in OS.

Purpose: Chemotherapy and accelerated superfractionated radiotherapy were prospectively applied for inflammatory breast carcinoma with the intent of breast conservation. The efficacy, failure patterns, and patient tolerance utilizing this approach were analyzed., Methods and Materials: Between 1983 and 1996, 52 patients with inflammatory breast carcinoma presented to the Medical College of Virginia Hospitals of VCU and the New England Medical Center. Thirty-eight of these patients were jointly evaluated in multidisciplinary breast clinics and managed according to a defined prospectively applied treatment policy. Patients received induction chemotherapy, accelerated superfractionated radiotherapy, selected use of mastectomy, and concluded with additional chemotherapy. The majority were treated with 1.5 Gy twice daily to field arrangements covering the entire breast and regional lymphatics. An additional 18-21 Gy was then delivered to the breast and clinically involved nodal regions. Total dose to clinically involved areas was 63-66 Gy. Following chemoradiotherapy, patients were evaluated with physical examination, mammogram, and fine needle aspiration x 3. Mastectomy was reserved for those patients with evidence of persistent or progressive disease in the involved breast. All patients received additional chemotherapy., Results: Median age was 51 years. Median follow-up was 23.9 months (6-86) months. The breast preservation rate at the time of last follow-up was 74%. The treated breast or chest wall as the first site of failure occurred in only 13%, and the ultimate local control rate with the selected use of mastectomy was 74%. Ten patients underwent mastectomy, 2 of which had pathologically negative specimens despite a clinically palpable residual mass. Response to chemotherapy was predictive of treatment outcome. Of the 15 patients achieving a complete response, 87% remain locoregionally controlled without the use of mastectomy. Five-year overall survival for complete responders was 68%. This is in contrast to the 14% 5-year overall survival observed with incomplete responders. The 5-year actuarial disease-free survival and overall survival for the entire patient cohort was 11% and 33%, respectively. All patients tolerated irradiation with limited acute effects, of which all were managed conservatively., Conclusion: Our experience demonstrates that induction chemotherapy, accelerated superfractionated radiotherapy, and the selected use of mastectomy results in excellent locoregional control rates, is well tolerated, and optimizes breast preservation. Based on our present results, we recommend that a patient's response to induction chemotherapy guide the treatment approach used for locoregional disease, such that mastectomy be reserved for incomplete responders and avoided in those achieving a complete response.

Background and Objectives: Local excision of rectal carcinoma has primarily been limited to patients with small (< or =3 cm), early rectal carcinoma. We wanted to determine whether local excision (transanal or transacral), when combined with selective chemoradiation therapy, would be adequate treatment for patients with larger (>3 cm) and more advanced T3 and N1 tumors., Methods: A prospective study of 20 patients with clinical T1-T3, N0-N1 rectal carcinoma was initiated in 1990. Local excision (transanal or transacral) was performed on all patients. Sixteen patients were treated with postoperative 5-fluorouracil (5-FU) and leucovorin (LV) combined with radiation therapy; six high-risk patients (T3 or N1) received an additional 6 months of 5-FU and LV. All patients were followed for a minimum of 4 years., Results: Tumor size ranged from 2 to 5.5 cm (mean, 3.6 cm). Histology revealed well or moderate differentiation (19/20), gross or microscopic ulceration (14/20), and vessel invasion (5/20). Mucosal margins were 3-12 mm (mean, 8.3 mm); radial margins were clear in all patients except one (microscopically positive). Five patients had T3 tumors; two had node positive tumors (N1). With a median follow-up of 56 months (48-71), there have been no local or regional failures and two patients have died from metastatic disease., Conclusions: Local excision, when combined with selective chemoradiation therapy, can be safely applied to patients with large (>3 cm) and more advanced T3 and N1 rectal carcinomas.

Purpose: To develop and implement a non-invasive immobilization system guided by a dedicated quality assurance (QA) program for dynamic intensity-modulated radiotherapy (IMRT) of intracranial and head and neck disease, with IMRT delivered using the NOMOS Corporation's Peacock System and MIMiC collimator., Methods and Materials: Thermoplastic face masks are combined with cradle-shaped polyurethane foaming agents and a dedicated quality assurance program to create a customized headholder system (CHS). Plastic shrinkage was studied to understand its effect on immobilization. Fiducial points for computerized tomography (CT) are obtained by placing multiple dabs of barium paste on mask surfaces at intersections of laser projections used for patient positioning. Fiducial lines are drawn on the cradle along laser projections aligned with nasal surfaces. Lateral CT topograms are annotated with a crosshair indicating the origin of the treatment planning and delivery coordinate system, and with lines delineating the projections of superior-inferior field borders of the linear accelerator's secondary collimators, or with those of the fully open MIMiC. Port films exposed with and without the MIMIC are compared to annotated topograms to measure positional variance (PV) in superior-inferior (SI), right-left (RL), and anterior posterior (AP) directions. MIMiC vane patterns superposed on port films are applied to verify planned patterns. A 12-patient study of PV was performed by analyzing positions of 10 anatomic points on repeat CT topograms, plotting histograms of PV, and determining average PV., Results and Discussion: A 1.5+/-0.3 mm SD shrinkage per 70 cm of thermoplastic was observed over 24 h. Average PV of 1.0+/-0.8, 1.2+/-1.1, and 1.3+/-0.8 mm were measured in SI, AP, and RL directions, respectively. Lateral port films exposed with and without the MIMiC showed PV of 0.2+/-1.3 and 0.8+/-2.2 mm in AP and SI directions. Vane patterns superimposed on port films consistently verified the planned patterns., Conclusion: The CHS provided adequately reproducible immobilization for dynamic IMRT, and may be applicable to decrease PV for other cranial and head and neck external beam radiation therapy.

The extent of positivity of the final excision margin in relationship to other relevant factors was evaluated as a predictor for local recurrence after breast conservation therapy (BCT). As part of an institutional practice policy for BCT in 509 stage I/II breast carcinomas, 105 cases had a final excision margin, which was positive. The median age for this cohort was 58 years and the median follow-up was 86 months. All positive margin patients received whole breast irradiation to 50 Gy-50.4 Gy followed by a boost to the tumor bed for an additional 20 Gy. The extent of positivity (EOP) of the excision margin was graded according to a four-point scale: focal, minimal, moderate, extensive. Cases were then analyzed for local failure according to EOP grade, histology, age, tumor size, total excision volume, re-excision, tamoxifen therapy, and chemotherapy. A focal or minimal EOP grade was found in 70% of specimens while an additional 26% were moderate or extensive. The incidence of invasive carcinoma with prominently associated DCIS was significantly greater in cases with an EOP grade of moderate/extensive. There were nine ipsilateral breast recurrences, eight of which could be evaluated for EOP grade. All recurrences were in or near the previous biopsy cavity. A Kaplan-Meier plot of freedom from local failure showed a significant (P = 0.008) difference between cases grouped by EOP grade of focal/minimal as compared to moderate/extensive. A Cox proportional hazards regression model found that the only variable significantly related at the P < or = 0.05 level to local failure was an EOP grade of moderate/extensive. For breast excision specimens with a positive final margin, an EOP grade of moderate/extensive is a predictor for local recurrence after BCT, which may be independent of other variables such as age or histology.

In spite of the recent recognition of specific genes associated with an elevated lifetime incidence risk of breast cancer, the molecular mechanisms of breast tumor formation remain largely unknown. Tumorigenesis is thought to be highly complex, likely involving the accumulation of 5-10 genetic and epigenetic events. Recent investigations have begun to identify some of these events, and in vitro model systems for breast tumorigenesis, including radiation-induced breast cancer, are expected to provide further insight. Normal human breast epithelial cells exhibit a finite life span, both in vivo and in vitro. A critical event in oncogenic transformation is the ability of cells to multiply indefinitely, a phenomenon referred to as "immortalization." Using human papillomavirus (HPV) oncogenes, multiple normal breast epithelial subtypes have been shown to have distinct susceptibilities to immortalization by the HPV E6 and E7 oncogenes. Because HPV E6 and E7 inactivate two well-known tumor suppressor proteins, p53 and Rb, respectively, this suggests that a cell-type-specific predominance exists with respect to these tumor suppressor pathways. Additional evidence for variability to oncogenic stimuli among normal breast epithelial cells is provided by findings of locally confined loss of heterozygosity. An in vitro model of radiation-induced breast cancer is associated with early abrogation of p53 function. The resultant pair of normal and radiation-transformed breast epithelial cells serves as a useful system to identify other genes critically relevant to breast tumorigenesis. These and other models should help further define the molecular mechanisms underlying the early steps of breast cancer formation.

The high-risk human papillomaviruses (HPVs) are associated with carcinomas of the cervix and other genital tumors. Previous studies have identified two viral oncoproteins, E6 and E7, which are expressed in the majority of HPV-associated carcinomas. The ability of high-risk HPV E6 protein to immortalize human mammary epithelial cells (MECs) has provided a single-gene model to study the mechanisms of E6-induced oncogenic transformation. In this system, the E6 protein targets the p53 tumor suppressor protein for degradation, and mutational analyses have shown that E6-induced degradation of p53 protein is required for MEC immortalization. However, the inability of most dominant-negative p53 mutants to induce efficient immortalization of MECs suggests the existence of additional targets of the HPV E6 oncoprotein. Using the yeast two-hybrid system, we have isolated a novel E6-binding protein. This polypeptide, designated E6TP1 (E6-targeted protein 1), exhibits high homology to GTPase-activating proteins for Rap, including SPA-1, tuberin, and Rap1GAP. The mRNA for E6TP1 is widely expressed in tissues and in vitro-cultured cell lines. The gene for E6TP1 localizes to chromosome 14q23.2-14q24.3 within a locus that has been shown to undergo loss of heterozygosity in malignant meningiomas. Importantly, E6TP1 is targeted for degradation by the high-risk but not the low-risk HPV E6 proteins both in vitro and in vivo. Furthermore, the immortalization-competent but not the immortalization-incompetent HPV16 E6 mutants target the E6TP1 protein for degradation. Our results identify a novel target for the E6 oncoprotein and provide a potential link between HPV E6 oncogenesis and alteration of a small G protein signaling pathway.

Previously (Liu et al, Cancer Res., 56: 3371-3379, 1996), we isolated a novel serine protease-like gene--Normal Epithelial Cell Specific-1 (NES1)--that is expressed in normal mammary epithelial cells but is down-regulated in most breast cancer cell lines. Here, we demonstrate that stable expression of NES1 in the NES1-negative MDA-MB-231 breast cancer cell line suppressed the oncogenicity as revealed by inhibition of the anchorage-independent growth and tumor formation in nude mice. Fluorescence in situ hybridization localized the NES1 gene to chromosome 19q13.3, a region that contains genes for related proteases (including the prostate-specific antigen) and is rearranged in human cancers. Similar to breast cancer cell lines, prostate cancer cell lines also lacked NES1 mRNA and protein expression. Together, these results strongly suggest a tumor-suppressor role for NES1 in breast and prostate cancer.

Purpose: To verify that optimized dose distributions provided by an intensity-modulated radiation therapy (IMRT) system are delivered accurately to human patients., Methods and Materials: Anthropomorphic phantoms are used to measure IMRT doses. Four types of verification are developed for: I) system commissioning with beams optimized to irradiate simulated targets in phantoms, II) plans with patient-optimized beams directed to phantoms simulating the patient, III) patient-phantom hybrid plans with patient-optimized beams calculated in phantom without further optimization, and IV) in vivo measurements. Phantoms containing dosimeters are irradiated with patient-optimized beams. Films are scanned and data were analyzed with software. Percent difference between verified and planned maximum target doses is defined as "dose discrepancy" (deltavp). The frequency distribution of type II deltavp from 204 verification films of 92 IMRT patients is fit to a Gaussian. Measurements made in vivo yield discrepancies specified as deltaivp, also fit to a Gaussian., Results and Discussion: Verification methods revealed three systematic errors in plans that were corrected prior to treatment. Values of [deltavp] for verification type I are <2%. Type II verification discrepancies are characterized by a Gaussian fit with a peak 0.2% from the centroid, and 158 [deltavp] <5%. The 46 values of [deltavp] >5% arise from differences between phantom and patient geometry, and from simulation, calculation, and other errors. Values of [deltavp] for verification III are less than half of the values of [deltavp] for verification II. A Gaussian fit of deltaivp from verification IV shows more discrepancy than the fit of deltavp, attributed to dose gradients in detectors, and exacerbated by immobilization uncertainty., Conclusions: Dosimetric verification is a critical step in the quality assurance (QA) of IMRT. Hybrid Verification III is suggested as a preliminary quality standard for IMRT.

Purpose: A prospectively applied treatment policy for breast-conserving therapy used margin assessment as the exclusive guide to the intensity of therapy directed at the tumor-bearing quadrant., Methods and Materials: From 1982-1994, there were 509 treated Stage I and II breast carcinomas with a median follow-up of 72 months. For operational purposes, tumor excision margins were prospectively defined as: > 5 mm, 2.1-5 mm, > 0 < or = 2 mm, and positive. If a margin was assessed as < or = 2 mm or indeterminate, and it was deemed cosmetically feasible, a reexcision of the tumor bed would be performed. All patients received whole breast irradiation to 50-50.4 Gy. The following scheme for tumor bed boost irradiation as a function of final margin status (FMS) was observed: (a) Minimal risk = no tumor found on reexcision, no boost performed; (b) low risk = FMS > 5 mm, boost of 10 Gy; intermediate risk = FMS 2.1-5 mm, boost to 14 Gy; high risk = FMS < or = 2 mm or positive, boost to 20 Gy. Cases were analyzed for local failure (LF) with respect to histology (invasive ductal (IDC), IDC with associated DCIS (IDC/DCIS), invasive lobular (ILC)), age, tumor size, total excision volume, reexcision, total dose, tamoxifen therapy, and chemotherapy., Results: There were 19 breast recurrences for a Kaplan-Meier local failure rate for all cases at 5 and 10 years of 2.7% and 7.1%, respectively. Local failure in the first 4 years of follow-up was rare, with a mean annual incidence rate of 0.25% that rose to a mean of 1.1% in subsequent years. Univariate results of Cox proportional hazards regression survival models found positive FMS (p = 0.02), IDC/DCIS (p = 0.04) and age (0.0006) as significantly associated with local failure. In a multivariable model of FMS and IDC/DCIS, FMS retained significance (p = 0.01) but IDC/DCIS was borderline (p = 0.06). When FMS and age were included in a multivariable model, there was a significant interaction (p = 0.01) between the two variables. There was a significant increase in the relative risk of LF for age < or = 45 years (range 11.1-17.4), irrespective of FMS category. Although excellent overall control rates were achieved for patients > 45 years, for younger patients LF rates appeared to remain proportional to the relative closeness of the FMS, despite rigorous dose escalation., Conclusions: Graded tumor-bed dose escalation in response to FMS results in an exceptionally low risk of "early" local recurrence within the first 5 years of follow-up. However, this strategy is unable to completely overcome the longer term adverse influence of young age and positive FMS.

To compare the dosimetry achievable with an intensity modulated radiotherapy (IMR) system to that of stereotactic radiosurgery (SRS) for an irregularly shaped moderate size target. A treatment plan was selected from 109 single fraction SRS cases having had multiple non-coplanar arc therapy using a 6 MV linear accelerator fitted with circular tertiary collimators 1.00 to 4.00 cm in diameter at isocenter. The CT scan with delineated regions of interest was then entered into an IMR treatment planning system and optimized dose distributions, using a back projection technique for dynamic multileaf collimator delivery, were generated with a stimulated annealing algorithm. Dose volume histograms (DVH), homogeneity indices (HI), conformity indices (CI), minimum and maximum doses to surrounding highly sensitive intracranial structures, as well as the volume of tissue treated to > 80, 50, and 20% of the prescription dose from the IMR plan were then compared to those from the single isocenter SRS plan used and a hypothetical three isocenter SRS plan. For an irregularly shaped target, the IMR plan produced a HI of 1.08 and CI of 1.50 compared to 1.75 and 4.41, respectively, for the single isocenter SRS plan (SRS1) and 3.33 and 3.43 for the triple isocenter SRS plan (SRS3). The maximum and minimum doses to surrounding critical structures were less with the IMR plan in comparison to both SRS plans. However, the volume of non-target tissue treated to > 80, 50, and 20% of the prescription dose with the IMR plan was 137, 170, and 163%, respectively, of that treated with the SRS1 plan and 85, 100, and 123% of the volume when compared to SRS3 plan. The IMR system provided more conformal target doses than were provided by the single isocenter or three isocenter SRS plans. IMR delivered less dose to critical normal tissues and provided increased homogeneity within the target volume for a moderate size irregularly shaped target, at the cost of a larger penumbra.

The p53 protein has become a subject of intense interest since the discovery that about 50% of human cancers carry p53 mutations. Mutations in the p53 gene are the most frequent genetic lesions in breast cancer, suggesting a critical role for p53 protein in normal mammary epithelial cell (MEC) growth control. We previously demonstrated that abrogation of the p53 function by a cancer-derived p53 mutant, del239, was sufficient to induce immortalization of normal MECs. To further extend these findings and to examine the mechanism of mutant p53-induced immortalization of MECs, we tested the immortalizing ability of four selected p53 mutants (R175H, R248W, R249S, and R273H), which involve residues that cluster close to N239 in the three-dimensional structure and which are critical for the DNA-binding function of p53. Interestingly, two of these mutants (R175H and R249S) reproducibly immortalized 76N normal MECs, whereas the other two mutants (R248W and R273H) induced an extension of life span but not immortalization. These results further substantiate that selective ablation of p53 function with dominant-negative mutants is sufficient for immortalization of MECs. To determine whether abrogation of the transactivation function of endogenous p53 was important for the differential immortalizing ability of p53 mutants, we measured the effects of mutant p53 on the endogenous wild-type p53-mediated transactivation of a chloramphenicol acetyltransferase reporter linked to a consensus p53 binding DNA sequence in transiently transfected 76N MECs. All of the mutants, regardless of their immortalizing phenotype, abrogated the endogenous wild-type p53-mediated transactivation to a similar extent. Thus, abrogation of transactivation function is not sufficient for mutant p53-induced immortalization of normal MECs. The p53-immortalized MECs showed substantial telomerase activity; however, induction of telomerase activity occurred at late passages and was undetectable in mutant p53-expressing cells prior to immortalization. We suggest that mechanisms other than abrogation of transactivation and induction of telomerase activity determine the differential MEC-immortalizing behavior of various p53 mutants.

Purpose: A two-step procedure is described for accurate planning of stereotactic brain implants prior to head-ring fixation., Methods and Materials: Approximately 2 weeks prior to implant a CT scan without the head ring is performed for treatment-planning purposes. An entry point and a reference point, both marked with barium and later tattooed, facilitate planning and permit correlation of the images with a later CT scan. A plan is generated using a conventional treatment-planning system to determine the number and activity of I-125 seeds required and the position of each catheter. I-125 seed anisotropy is taken into account by means of a modification to the treatment planning program. On the day of the implant a second CT scan is performed with the head ring affixed to the skull and with the same points marked as in the previous scan. The planned catheter coordinates are then mapped into the coordinate system of the second CT scan by means of a manual translational correction and a computer-calculated rotational correction derived from the reference point coordinates in the two scans., Results: The rotational correction algorithm was verified experimentally in a Rando phantom before it was used clinically. For analysis of the results with individual patients a third CT scan is performed 1 day following the implant and is used for calculating the final dosimetry., Conclusion: The technique that is described has two important advantages: 1) the number and activity of seeds required can be accurately determined in advance; and 2) sufficient time is allowed to derive the best possible plan.

Background: The purpose of this study was to evaluate the feasibility of breast-conserving therapy involving limited surgery and definitive radiotherapy as a treatment for Paget's disease, and to determine the disease free and overall survival associated with this approach., Methods: The authors retrospectively reviewed the charts of all patients treated during the period 1980-1994 for Paget's disease of the breast who did not present with a palpable mass or mammographic density. Through a collaborative review, 30 cases were identified. A biopsy confirming the presence of typical Paget's cells was performed on all patients. All patients received external beam radiotherapy to the breast, with a median dose of 50 gray (Gy). Ninety-seven percent received a boost to the remaining nipple or tumor bed, with a median dose to the tumor bed of 61.5 Gy., Results: The median follow-up for surviving patients was 62 months. Three patients (10%) developed a recurrence in the breast as the only site of first failure, and 2 additional patients (7%) experienced failure in the breast as a component of first failure. The median time to local failure was 69 months. The 5- and 8-year actuarial estimates of local failure as the only site of first failure were 9% (95% confidence interval [CI], 0-20%) and 16% (95% CI, 0-31%), respectively. Of the 5 patients with local failures, 3 were among 22 patients (14%) who underwent complete resection of the nipple or nipple-areola complex, compared with 2 failures among 6 patients (33%) after partial resection (P = 0.29). There were no failures among 2 patients who had a biopsy only. Four of 5 local failures were salvaged by mastectomy, and 3 of these patients were free of disease after a median follow-up of 52 months. The 5- and 8-year estimates of disease free survival for the overall series were both 95% (95% CI, 87-100%); cause specific overall survival was 100% at 8 years., Conclusions: Breast-conserving therapy involving complete resection of the nipple-areola complex followed by definitive radiotherapy is a viable alternative to mastectomy in the treatment of Paget's disease. High rates of disease free and cause specific survival, in addition to adequate local control, justify consideration of a conservative approach.

Purpose: To evaluate the relative utility of interstitial implant as a technique for tumor bed dose escalation and assess technical factors related to outcome., Methods and Materials: From 1982-1994, a prospectively applied institutional policy of margin-directed boost dose escalation to the tumor bed was followed whereby interstitial implantation was commonly employed for a final margin status (FMS) < or = 2 mm. There were 509 treated breasts, of which 127 received an implant boost. For purposes of comparison, cases were broadly classed as "implant" (all FMS < or = 2 mm) and "nonimplant" (FMS < or = 2 mm or FMS > 2 mm). The implant target volume was determined at completion of whole breast irradiation by clinical assessment. All implants were constructed in accordance with a preplanning algorithm designed to maximize dose homogeneity within a prescription isodose goal of 0.50 Gy/h for 40 h. Local control and cosmetic outcome were evaluated with respect to extent of tumor, histopathology, FMS, extent of surgery, and systemic adjuvant therapy. Implant quality was assessed using four calculated parameters: strand separation quotient (SSQ), planar separation quotient (PSQ), global separation quotient (GSQ), and dose homogeneity index (DHI). The mean implant volume was 48.3 +/- 20 cc, the mean prescribed dose rate was 0.46 +/- 0.08 Gy/h, and the mean total implant dose was 19.94 +/- 1.52 Gy., Results: Cosmetic outcome was good/excellent in 90% of implant and 83% of all nonimplant cases, which was not statistically different. Cosmesis was significantly superior with implant when compared to nonimplant cases receiving an external boost of 20 Gy. Logistic regression analyses of implant cases revealed that reexcision volume and decreased DHI were associated with adverse cosmesis. There were 10 local failures in the implanted patients (4 within the prescribed isodose volume, 5 at the periphery, and 1 elsewhere in the breast). The local failure rate at 5 and 7 years in the implanted group was 3.9 and 9.0%, respectively, compared to nonimplant cases with a margin < or = 2 mm of 3.2 and 3.2%, respectively. These differences were not significant. The crude local failure rate in patients with an associated DCIS component was 12% a compared to 3% in patients with pure invasive histology (p = 0.06). A proportional hazards survival model revealed a significant association of local failure with the performance of a reexcision and young age., Conclusion: We conclude that interstitial implant boost for breast conserving irradiation is associated with cosmesis that is superior than the same nominal dose of external beam boost, although this is highly dependent upon the technical quality of the source position and the relative uniformity of dose deposition. Breast implantation results in a rate of local control no better than dose-matched external beam boost in patients with a final margin < or = 2 mm. Local control with implantation might be further enhanced by increasing implant volume and/or improved target localization.

Background: The aim of this study was to evaluate the impact on disease recurrence and cosmetic outcome of tamoxifen treatment initiated after breast-conserving therapy (BCT)., Methods: Between 1982 and 1994, 498 women (509 breasts) were treated with BCT in accordance with a highly standardized institutional protocol. Adjuvant tamoxifen was administered to 130 patients (134 breasts), beginning 1-6 weeks after irradiation. The median ages and duration of follow-up for groups who received tamoxifen (TAM+) and no tamoxifen (TAM-) were 62.5 years/56 months and 53 years/60 months, respectively. The members of the TAM+ group were significantly older (P = 0.0001) and had increased incidences of positive axillary lymph nodes or undissected axilla (P = 0.001). There was a significant (P = 0.001) difference between the TAM+ and TAM- groups in the distribution of histopathologic subtypes; this reflected an increased proportion of associated ductal carcinoma in situ in the TAM- group. More extensive regional lymphatic irradiation was administered to the TAM+ group. Chemotherapy was administered to 15% of TAM+ and 28% (P = 0.003) of TAM- patients. There were no significant differences between the groups with respect to tumor size, reexcision, total excised tissue volume, final margin status, total radiation dose, or use of interstitial implant boost., Results: There was no significant difference between the TAM+ and TAM- groups in the overall distribution of cosmetic scores (P = 0.18). The 5-, 7-, and 10-year actuarial local failure rates for TAM+ versus TAM- patients were 0% versus 3.1%, 1.9% versus 5.4%, and 1.9% versus 8.4%, respectively. Multivariate regression analyses of potentially confounding variables revealed no significant associations between tamoxifen and either cosmetic outcome or local failure., Conclusions: Radiotherapy followed by tamoxifen has no adverse interactive effect on cosmesis, and tamoxifen is associated with a trend toward enhanced 5-year local control probability.

Malignant melanoma is associated with an excellent long-term prognosis when detected and treated at an early stage. Surgery alone is sufficient for patients with thin melanomas. Patients with thicker tumors, who are at higher risk for metastasis, may benefit from additional therapy beyond surgical removal of the tumor. Adjuvant therapies are designed to reduce the risk of melanoma recurrence. In particular, the immunotherapies, which boost the host's immune response to the cancer, are proving to be valuable adjuncts to surgery. Once melanoma has metastasized to a visceral organ, the prognosis is poor. Metastatic melanoma has a poor response to most conventional treatments. Boron neutron capture therapy is a novel approach to cancer management. It is a binary therapy combining low energy, nonionizing neutron irradiation with a stable isotope of naturally occurring boron avidly absorbed by the tumor. The combined approach currently under investigation results in highly selective tumor destruction.