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Purpose: Radiation therapy (RT) is mainly used for bladder preservation in patients with muscle-invasive bladder cancer. The response of urothelial tumors to RT remains unsatisfactory. We investigated the interaction of RT and tumor-associated macrophages (TAMs) in the context of bladder cancer radioresistance., Methods and Materials: We evaluated the therapeutic effects of RT and TAM distribution by establishing an ectopic allograft mouse model. A Transwell coculture system was used to simulate the interaction between TAMs and MB49 bladder cancer cells in the tumor microenvironment. Cytokines and chemokines were analyzed in irradiated MB49 cells. Colony formation and Boyden chamber assays were used to assess the cytotoxic effects and the effects of TAMs on MB49 cell invasion, respectively., Results: Local RT delayed primary tumor growth but promoted pulmonary metastases in C57BL/6 mice. Increased secretion of C-C motif chemokine ligand (CCL2) by irradiated MB49 cells, especially in the presence of M1-type TAMs, contributed to the infiltration of bone marrow-derived C-C motif chemokine receptor 2 (CCR2)-positive myeloid cells and the polarization of M1-type TAMs toward the M2 type to promote MB49 cell invasion. Blockade of CCL2-CCR2 activation by a CCR2 antagonist reversed the phenotypic TAM transformation and suppressed pulmonary metastases., Conclusions: Bladder cancer cells responded to RT by producing CCL2, which recruited TAM precursors from bone marrow and polarized M1-type TAMs toward the M2 type. This phenotypic TAM transformation promoted the pulmonary metastasis of bladder cancer cells after RT. Disrupting the CCL2-CCR2 signaling axis in combination with RT holds promise for improving RT efficacy in bladder cancer., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Purpose: To investigate the temporal and spatial infiltration of TRAMP-C1 tumors by myeloid-derived suppressor cells (MDSCs) after high-dose radiation therapy (RT), and to explore their effect on tumor growth., Methods and Materials: TRAMP-C1 intramuscularly tumors were irradiated with a single dose of 8 Gy or 25 Gy. The dynamics of infiltrated MDSCs and their intratumoral spatial distribution were assessed by immunohistochemistry and flow cytometry. Cytokine levels in the blood and tumor were analyzed by multiplex immunoassay. Mice were injected with anti-Gr-1 antibody to determine whether MDSCs affect tumor growth after RT., Results: CD11b + Gr-1 + MDSCs infiltrated TRAMP-C1 tumors irradiated with 25 Gy, but not 8 Gy, within 4 hours and recruitment persisted for at least 2 weeks. Both CD11b + Ly6G + Ly6C + polymorphonuclear-MDSCs (PMN-MDSCs) and CD11b + Ly6G - Ly6C hi monocytic-MDSCs (M-MDSCs) were involved. Tumor RT also increased the representation of both MDSC subpopulations in the spleen and peripheral blood. Levels of multiple cytokines were increased in the tumors at 2 weeks, including GM-CSF, G-CSF, CCL-3, CCL-5, CXCL-5, IL-6, IL-17α, and VEGF-a; while G-CSF, IL-6, and TNF-α levels increased in the blood. PMN-MDSCs aggregated in the central necrotic region of the irradiated tumors over time, where they were associated with avascular hypoxia (CD31 - PIMO + ). MDSCs expressed the proangiogenic factor, matrix metalloproteinase-9, and, within the necrotic area, high levels of arginase-1 and indoleamine 2,3-dioxygenase. Depletion of PMN-MDSCs by Gr-1 antibody increased the efficacy of high-dose RT., Conclusions: PMN-MDSCs infiltrate TRAMP-C1 tumors after high-dose RT. Their spatial distribution suggests they are involved in the evolution of an intratumoral state of necrosis associated with avascular hypoxia, and their phenotype is consistent with them being immunosuppressive. They appear to promote tumor growth after RT, making them a prime therapeutic target for therapeutic intervention. Assessment of MDSCs and cytokine levels in blood could be an index of the need for such an intervention., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Purpose: A prospective trial of proton therapy for breast cancer revealed an increased rib fracture rate of 7%, which is higher than the expected rate based on the literature on photon therapies. We aim to evaluate the hypothesis that the increased relative biological effectiveness (RBE) at the distal edge of proton beams is the cause., Methods and Materials: We combined the cohort from the prospective clinical trial and a retrospective cohort from a database. Monte Carlo simulations were performed to recalculate the physical dose and dose-averaged linear energy transfer (LETd). The first 10 ribs and fracture areas in patients with fractures were contoured and deformably registered. The LETd-weighted dose was used as a surrogate for biological effectiveness and compared with the conventional fixed RBE of 1.1. Dose to 0.5 cm 3 of the ribs (D0.5) was selected to analyze the dose-response relationship using logistic regression. We chose an alpha/beta ratio of 3 to calculate the biological effective dose in Gy 3 (RBE)., Results: Thirteen of 203 patients in the cohorts exhibited a total of 25 fractures. The LETd in fractured areas is increased (6.1 ± 2.0 keV/μm, mean ± standard deviation), suggesting possible end-of-range radiobiological effects with increased RBE. The D0.5 of the fractured ribs is 80.3 ± 9.4 Gy 3 (RBE) with a generic factor of 1.1 and is relatively low compared with historical photon results. On the other hand, the D0.5 of the fractured ribs is 100.0 ± 12.5 Gy 3 (RBE) using the LETd-based model with a dose-response curve that is more consistent with historical photon data., Conclusions: The increased rib fracture rate seen in our trial is probably associated with the increased LETd and RBE at the distal edge of proton beams. This phenomenon warrants further investigation and possible integration of LETd into treatment planning and optimization in proton therapy., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Purpose: To identify predictors of radiation-induced liver disease (RILD) in patients with hepatocellular carcinoma (HCC) treated with proton beam therapy (PBT)., Methods: This multicenter study included 136 patients with HCC (eastern, n = 102; western, n = 34) without evidence of intrahepatic tumor progression after PBT. The RILD was defined as ascites with alkaline-phosphatase abnormality, grade ≥3 hepatic toxicity, or Child-Pugh score worsening by ≥2 within 4 months after PBT completion. The proton doses were converted to equivalent doses in 2-GyE fractions. The unirradiated liver volume (ULV) was defined as the absolute liver volume (LV) receiving <1 GyE; the standard liver volume (SLV) was calculated using body surface area. Possible correlations of clinicodosimetric parameters with RILD were examined., Results: The mean pretreatment LV was 85% of SLV, and patients with a history of hepatectomy (P < .001) or hepatitis B virus infection (P = .035) had significantly smaller LV/SLV. Nineteen (14%) patients developed RILD. Multivariate logistic regression analysis identified ULV/SLV (P = .001), gross tumor volume (P = .001), and Child-Pugh classification (P = .002) as independent RILD predictors, and mean liver dose and target-delivered dose were not associated with RILD occurrence. A "volume-response" relationship between ULV/SLV and RILD was consistently observed in both eastern and western cohorts. In Child-Pugh class-A patients whose ULV/SLV were ≥50%, 49.9%-40%, 39.9%-30% and <30%, the RILD incidences were 0%, 6%, 16%, and 39% (P < .001), respectively. For the Child-Pugh class-B group, the RILD incidences in patients with ≥60%, 59.9%-40%, and <40% of ULV/SLV were 0%, 14%, and 83% (P = .006), respectively., Conclusions: The ULV/SLV, not mean liver dose, independently predicts RILD in patients with HCC undergoing PBT. The relative and absolute contraindications for Child-Pugh class-A patient's ULV/SLV are <50% and <30%, and <60% and <40% for Child-Pugh class-B patients, respectively. Our results indicate that the likelihood of hepatic complications for PBT is dictated by similar metrics as that for surgery., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Purpose: To investigate whether changes in the volume transfer coefficient (K(trans)) in a growing tumor could be used as a surrogate marker for predicting tumor responses to radiation therapy (RT) and chemotherapy (CT)., Methods and Materials: Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) was consecutively performed on tumor-bearing mice, and temporal and spatial changes of K(trans) values were measured along with tumor growth. Tumor responses to RT and CT were studied before and after observed changes in K(trans) values with time., Results: Dynamic changes with an initial increase and subsequent decline in K(trans) values were found to be associated with tumor growth. When each tumor was divided into core and peripheral regions, the K(trans) decline was greater in core, although neither vascular structure or necrosis could be linked to this spatial difference. Tumor responses to RT were worse if applied after the decline of K(trans), and there was less drug distribution and cell death in the tumor core after CT., Conclusion: The K(trans) value in growing tumors, reflecting the changes of tumor microenvironment and vascular function, is strongly associated with tumor responses to RT and CT and could be a potential surrogate marker for predicting the tumor response to these treatments., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Purpose: To investigate the role of galectin-1 in patients with cervical cancer after definitive radiation therapy., Methods and Materials: We reviewed 154 patients with International Federation of Gynecology and Obstetrics stage I-II squamous cell carcinoma. Patients underwent curative-intent radiation therapy. Paraffin-embedded tissues were analyzed using immunohistochemistry staining for galectin-1. The rates of cancer-specific survival (CSS), local recurrence (LR), and distant metastasis were compared among patient tissue samples with no, weak, and strong galectin-1 expression. The Kaplan-Meier method and the Cox proportional hazard model with hazard ratios and 95% confidence intervals (CIs) were used for univariate and multivariate analyses, respectively., Results: The areas under the curve for the intracellular expression scores of galectin-1 for both LR and CSS were significantly higher than those for stromal expression. There were no significant differences in the demographic data, such as stage and serum tumor markers, between patients with and without intracellular expression of galectin-1 in cancer tissue samples. Using multivariate analyses, the hazard ratios of LR and CSS were 2.60 (95% CI 1.50-4.52) (P=.001) and 1.94 (95% CI 1.18-3.19) (P=.010), respectively., Conclusion: Galectin-1 is an independent prognostic factor associated with LR and CSS in stage I-II cervical cancer patients undergoing definitive radiation therapy. Further studies targeting galectin-1 may improve the local control of cervical cancer., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Purpose: To investigate vascular responses during fractionated radiation therapy (F-RT) and the effects of targeting pericytes or bone marrow-derived cells (BMDCs) on the efficacy of F-RT., Methods and Materials: Murine prostate TRAMP-C1 tumors were grown in control mice or mice transplanted with green fluorescent protein-tagged bone marrow (GFP-BM), and irradiated with 60 Gy in 15 fractions. Mice were also treated with gefitinib (an epidermal growth factor receptor inhibitor) or AMD3100 (a CXCR4 antagonist) to examine the effects of combination treatment. The responses of tumor vasculatures to these treatments and changes of tumor microenvironment were assessed., Results: After F-RT, the tumor microvascular density (MVD) was reduced; however, the surviving vessels were dilated, incorporated with GFP-positive cells, tightly adhered to pericytes, and well perfused with Hoechst 33342, suggesting a more mature structure formed primarily via vasculogenesis. Although the gefitinib+F-RT combination affected the vascular structure by dissociating pericytes from the vascular wall, it did not further delay tumor growth. These tumors had higher MVD and better vascular perfusion function, leading to less hypoxia and tumor necrosis. By contrast, the AMD3100+F-RT combination significantly enhanced tumor growth delay more than F-RT alone, and these tumors had lower MVD and poorer vascular perfusion function, resulting in increased hypoxia. These tumor vessels were rarely covered by pericytes and free of GFP-positive cells., Conclusions: Vasculogenesis is a major mechanism for tumor vessel survival during F-RT. Complex interactions occur between vessel-targeting agents and F-RT, and a synergistic effect may not always exist. To enhance F-RT, using CXCR4 inhibitor to block BM cell influx and the vasculogenesis process is a better strategy than targeting pericytes by epidermal growth factor receptor inhibitor., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Purpose: The microvasculature of a tumor plays an important role in its response to radiation therapy. Dynamic contrast-enhanced magnetic resonance imaging (DCE MRI) and blood oxygen level-dependent (BOLD) MRI are both sensitive to vascular characteristics. The present study proposed a partial irradiation approach to a xenograft tumor to investigate the intratumoral response to radiation therapy using DCE and BOLD MRI., Methods and Materials: TRAMP-C1 tumors were grown in C57BL/6J mice. Partial irradiation was performed on the distal half of the tumor with a single dose of 15 Gy. DCE MRI was performed to derive the endothelium transfer constant, K(trans), using pharmacokinetic analysis. BOLD MRI was performed using quantitative R2 measurements with carbogen breathing. The histology of the tumor was analyzed using hematoxylin and eosin staining and CD31 staining to detect endothelial cells. The differences between the irradiated and nonirradiated regions of the tumor were assessed using K(trans) values, ΔR2 values in response to carbogen and microvascular density (MVD) measurements., Results: A significantly increased K(trans) and reduced BOLD response to carbogen were found in the irradiated region of the tumor compared with the nonirradiated region (P<.05). Histologic analysis showed a significant aggregation of giant cells and a reduced MVD in the irradiated region of the tumor. The radiation-induced difference in the BOLD response was associated with differences in MVD and K(trans)., Conclusions: We demonstrated that DCE MRI and carbogen-challenge BOLD MRI can detect differential responses within a tumor that may potentially serve as noninvasive imaging biomarkers to detect microvascular changes in response to radiation therapy., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Purpose: To study the prognostic value of human papillomavirus (HPV) genotypes in patients with advanced cervical cancer treated with radiation therapy (RT) alone or concurrent chemoradiation therapy (CCRT)., Methods and Materials: Between August 1993 and May 2000, 327 patients with advanced squamous cell carcinoma of the cervix (International Federation of Gynecology and Obstetrics stage III/IVA or stage IIB with positive lymph nodes) were eligible for this study. HPV genotypes were determined using the Easychip® HPV genechip. Outcomes were analyzed using Kaplan-Meier survival analysis and the Cox proportional hazards model., Results: We detected 22 HPV genotypes in 323 (98.8%) patients. The leading 4 types were HPV16, 58, 18, and 33. The 5-year overall and disease-specific survival estimates for the entire cohort were 41.9% and 51.4%, respectively. CCRT improved the 5-year disease-specific survival by an absolute 9.8%, but this was not statistically significant (P=.089). There was a significant improvement in disease-specific survival in the CCRT group for HPV18-positive (60.9% vs 30.4%, P=.019) and HPV58-positive (69.3% vs 48.9%, P=.026) patients compared with the RT alone group. In contrast, the differences in survival with CCRT compared with RT alone in the HPV16-positive and HPV-33 positive subgroups were not statistically significant (P=.86 and P=.53, respectively). An improved disease-specific survival was observed for CCRT treated patients infected with both HPV16 and HPV18, but these differenced also were not statistically significant., Conclusions: The HPV genotype may be a useful predictive factor for the effect of CCRT in patients with advanced squamous cell carcinoma of the cervix. Verifying these results in prospective trials could have an impact on tailoring future treatment based on HPV genotype., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Purpose: To compare clinical behaviors and treatment outcomes between patients with squamous cell carcinoma (SCC) and adenocarcinoma/adenosquamous carcinoma (AC/ASC) of the cervix treated with radical hysterectomy (RH) and adjuvant radiotherapy (RT) or concurrent chemoradiotherapy (CCRT)., Methods and Materials: A total of 318 Stage IB-IIB cervical cancer patients, 202 (63.5%) with SCC and 116 (36.5%) with AC/ASC, treated by RH and adjuvant RT/CCRT, were included. The indications for RT/CCRT were deep stromal invasion, positive resection margin, parametrial invasion, or lymph node (LN) metastasis. Postoperative CCRT was administered in 65 SCC patients (32%) and 80 AC/ASC patients (69%). Patients with presence of parametrial invasion or LN metastasis were stratified into a high-risk group, and the rest into an intermediate-risk group. The patterns of failure and factors influencing survival were evaluated., Results: The treatment failed in 39 SCC patients (19.3%) and 39 AC/ASC patients (33.6%). The 5-year relapse-free survival rates for SCC and AC/ASC patients were 83.4% and 66.5%, respectively (p = 0.000). Distant metastasis was the major failure pattern in both groups. After multivariate analysis, prognostic factors for local recurrence included younger age, parametrial invasion, AC/ASC histology, and positive resection margin; for distant recurrence they included parametrial invasion, LN metastasis, and AC/ASC histology. Compared with SCC patients, those with AC/ASC had higher local relapse rates for the intermediate-risk group but a higher distant metastasis rate for the high-risk group. Postoperative CCRT tended to improve survival for intermediate-risk but not for high-risk AC/ASC patients., Conclusions: Adenocarcinoma/adenosquamous carcinoma is an independent prognostic factor for cervical cancer patients treated by RH and postoperative RT. Concurrent chemoradiotherapy could improve survival for intermediate-risk, but not necessarily high-risk, AC/ASC patients., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Purpose: To investigate vasculatures and microenvironment in tumors growing from preirradiated tissues (pre-IR tumors) and study the vascular responses of pre-IR tumors to radiation and antiangiogenic therapy., Methods and Materials: Transgenic adenocarcinoma of the mouse prostate C1 tumors were implanted into unirradiated or preirradiated tissues and examined for vascularity, hypoxia, and tumor-associated macrophage (TAM) infiltrates by immunohistochemistry. The origin of tumor endothelial cells was studied by green fluorescent protein-tagged bone marrow (GFP-BM) transplantation. The response of tumor endothelial cells to radiation and antiangiogenic agent was evaluated by apoptotic assay., Results: The pre-IR tumors had obvious tumor bed effects (TBE), with slower growth rate, lower microvascular density (MVD), and more necrotic and hypoxic fraction compared with control tumors. The vessels were dilated, tightly adhered with pericytes, and incorporated with transplanted GFP-BM cells. In addition, hypoxic regions became aggregated with TAM. As pre-IR tumors developed, the TBE was overcome at the tumor edge where the MVD increased, TAM did not aggregate, and the GFP-BM cells did not incorporate into the vessels. The vessels at tumor edge were more sensitive to the following ionizing radiation and antiangiogenic agent than those in the central low MVD regions., Conclusions: This study demonstrates that vasculatures in regions with TBE are mainly formed by vasculogenesis and resistant to radiation and antiangiogenic therapy. Tumor bed effects could be overcome at the edge of larger tumors, but where vasculatures are formed by angiogenesis and sensitive to both treatments. Vasculatures formed by vasculogenesis should be the crucial target for the treatment of recurrent tumors after radiotherapy., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Purpose: To study the outcomes of patients with adenocarcinoma/adenosquamous carcinoma (AC/ASC) of the cervix primarily treated with radiotherapy (RT), identify the prognostic factors, and evaluate the efficacy of concurrent chemoradiotherapy (CCRT) or salvage surgery., Methods and Materials: A total of 148 patients with Stage I-IVA AC/ASC of cervix after full-course definitive RT were included. Of the 148 patients, 77% had advanced stage disease. Treatment failure was categorized as either distant or local failure. Local failure was further separated into persistent tumor or local relapse after complete remission. The effectiveness of CCRT with cisplatin and/or paclitaxel was examined, and the surgical salvage rate for local failure was reviewed., Results: The 5-year relapse-free survival rate was 68%, 38%, 49%, 30%, and 0% for those with Stage IB/IIA nonbulky, IB/IIA bulky, IIB, III, and IVA disease, respectively, and appeared inferior to that of those with squamous cell carcinoma of the cervix treated using the same RT protocol. Incomplete tumor regression after RT, a low hemoglobin level, and positive lymph node metastasis were independent poor prognostic factors for relapse-free survival. CCRT with weekly cisplatinum did not improve the outcome for our AC/ASC patients. Salvage surgery rescued 30% of patients with persistent disease., Conclusion: Patients with AC/ASC of the cervix primarily treated with RT had inferior outcomes compared to those with squamous cell carcinoma. Incomplete tumor regression after RT was the most important prognostic factor for local failure. Salvage surgery for patients with persistent tumor should be encouraged for selected patients. Our results did not demonstrate a benefit of CCRT with cisplatin for this disease., (Copyright © 2011. Published by Elsevier Inc.)

Purpose: To study the prognostic value of the human papillomavirus (HPV) genotypes in cervical cancer patients undergoing radiotherapy., Patients and Methods: A total of 1,010 patients with cervical cancer after radiotherapy between 1993 and 2000 were eligible for this study. The HPV genotypes were determined by a genechip, which detects 38 types of HPV. The patient characteristics and treatment outcomes were analyzed using the Cox regression hazard model and classification and regression tree decision tree method., Results: A total of 25 genotypes of HPV were detected in 992 specimens (98.2%). The leading 8 types were HPV16, 58, 18, 33, 52, 39, 31, and 45. These types belong to two high-risk HPV species: alpha-7 (HPV18, 39, 45) and alpha-9 (HPV16, 31, 33, 52, 58). Three HPV-based risk groups, which were independent of established prognostic factors, such as International Federation of Gynecology and Obstetrics stage, age, pathologic features, squamous cell carcinoma antigen, and lymph node metastasis, were associated with the survival outcomes. The high-risk group consisted of the patients without HPV infection or the ones infected with the alpha-7 species only. Patients co-infected with the alpha-7 and alpha-9 species belonged to the medium-risk group, and the others were included in the low-risk group., Conclusion: The results of the present study have confirmed the prognostic value of HPV genotypes in cervical cancer treated with radiotherapy. The different effect of the alpha-7 and alpha-9 species on the radiation response deserves additional exploration., (Copyright © 2010 Elsevier Inc. All rights reserved.)

Purpose: To investigate the effects of single and fractionated doses of radiation on tumors and tumor-associated macrophages (TAMs), and to elucidate the potential of TAMs to influence tumor growth., Methods and Materials: A murine prostate cell line, TRAMP-C1, was grown in C57Bl/6J mice to 4-mm tumor diameter and irradiated with either 25 Gy in a single dose, or 60 Gy in 15 fractions. The tumors were removed at the indicated times and assessed for a variety of markers related to TAM content, activation status, and function., Results: In tumors receiving a single radiation dose, arginase (Arg-I), and cycloxygenase-2 (COX-2) mRNA expression increased as a small transient wave within 24 h and a larger persistent wave starting after 3 days. Inducible nitric oxide synthase (iNOS) mRNA was elevated only after 3 days and continued to increase up to 3 weeks. After fractionated irradiation, Arg-1 and COX-2 mRNA levels increased within 5 days, whereas iNOS was increased only after 10 fractions of irradiation had been given. Increased levels of Arg-I, COX-2, and, to a lesser extent, iNOS protein were found to associate with TAMs 1-2 weeks after tumor irradiation. Function of TAMs were compared by mixing them with TRAMP-C1 cells and injecting them into mice; TRAMP-C1 cells mixed with TAMs from irradiated tumors appeared earlier and grew significantly faster than those mixed with TAMs from unirradiated tumors or TRAMP-C1 alone., Conclusions: Tumor-associated macrophages in the postirradiated tumor microenvironment express higher levels of Arg-1, COX-2, and iNOS, and promote early tumor growth in vivo.

Purpose: To identify prognostic factors for local and distant relapse and perform risk stratification for patients with advanced cervical cancer treated with radiotherapy (RT) alone., Methods and Materials: A total of 1031 patients with Stage IB-IVA squamous cell carcinoma of the cervix treated with full-course RT but without any chemotherapy were included for analysis. Of these, 311 patients with nonbulky Stage IB-IIA disease were designated the reference group and the other 720 patients were the study group. The associations of stage, squamous cell carcinoma antigen (SCC-ag) level, hemoglobin level, age, cell differentiation, and pelvic lymph node status with treatment failure were evaluated. The independent prognostic factors were identified by multivariate analysis. The study group was further stratified into subgroups using combinations of these risk factors., Results: In the study group, independent risk factors for local relapse were advanced stage and age <45 years. The 5-year local relapse-free survival rate was 86% for patients > or =45 years with bulky Stage IB-IIA or IIB disease, and was even greater, up to 90% if the SCC-ag level was <2. In contrast, it was 65% for patients with Stage IIIB who were <45 years old. The independent risk factors for distant failure were advanced stage, SCC-ag level >2, and positive pelvic lymph nodes. The 5-year distant relapse-free survival rate was 83% for patients with bulky Stage IB-IIA and IIB disease, SCC-ag level <2, and negative lymph nodes and 43% for patients with Stage III, SCC-ag level >2, and positive lymph nodes., Conclusion: The risk of treatment failure in advanced-stage cervical cancer patients treated by RT alone can be more precisely predicted by risk stratification. A certain subgroup of patients had better control than the others. The benefit of treating these relatively low-risk patients with additional treatment such as concurrent chemotherapy should be further evaluated in prospective studies or meta-analyses.

Purpose: To study retrospectively the characteristics and survival of patients with recurrent squamous cell carcinoma (SCC) of the cervix after definitive radiotherapy (RT) and to identify subsets of patients who might benefit from aggressive salvage treatment., Methods and Materials: Between 1990 and 1999, 1292 patients with Stage I-IVA SCC of the cervix underwent full-course RT. Of the 1292 patients, 375 (29%) had either local or distant failure and were included in this analysis. The 35 patients (2.7%) with both pelvic and distant relapse were excluded. In the 162 patients with local failure, 71 (44%) had persistent disease and 91 (56%) had a relapse after complete tumor regression. Of these 162 patients, 47 (29%) received salvage surgery. In the 213 patients with distant failure, 46 (22%) had isolated para-aortic lymph node (PALN) metastasis, and 35 (76%) of them were treated with concurrent chemoradiotherapy/RT. Patients with supraclavicular lymph node (SCLN) relapse usually underwent concurrent chemoradiotherapy. Palliative chemotherapy and/or RT were given by decision of the responsible attending physician., Results: The independent prognostic factors for local failure were advanced stage and young age (<45 years) and, for distant failure, were advanced stage, positive pelvic lymph nodes, and high serum SCC-antigen levels. The 5-year overall survival rate was 10% and 11%, respectively, for patients with local or distant failure. For local relapse, the 5-year overall survival rate was 29% vs. 3% (p = 0.0001) for patients with vs. without salvage surgery and 22% vs. 9% vs. 4% for patients with tumors confined to the cervix, tumors extending but not beyond the cervix and adjacent tissues, and tumor extending beyond adjacent tissues but contained within the pelvis (p = 0.005). The survival rates, either with or without salvage surgery, were nearly identical between patients with persistent disease and those with relapse after complete regression. The 3-year overall survival rate was 34%, 28%, and 5% (p = 0.001), respectively, for patients with PALN relapse alone, SCLN relapse with or without PALN relapse, and relapse other than PALN and SCLN. Of the patients with PALN relapse alone, 27% survived >5 years., Conclusion: For recurrent SCC of the cervix after RT, patients with isolated PALN relapse salvaged by RT or combined chemoradiotherapy or those with cervical relapse salvaged by surgery can achieve long-term survival. Early detection of relapse with aggressive salvage treatment is important for achieving better outcome. Patients with persistent disease or relapse after complete remission had similar outcomes. Patients with SCLN relapse had a longer survival time than those with other metastases (except PALN), and palliative RT might be beneficial.

Purpose: Nasopharyngeal carcinoma is rare in the United States and common in southern China. Evaluating American patients treated using a uniform technique and staged with CT scanning, we determined whether Chinese and non-Chinese patients differ in presentation and outcome., Methods and Materials: Between 1979 and 1996, 172 patients treated at Massachusetts General Hospital received primary radiotherapy with curative intent for nasopharyngeal carcinoma. Forty-one patients (24%) were of Chinese descent, and 41% of cancers were classified as having lymphoepithelioma histologic features. Most patients received twice-daily radiotherapy and a brachytherapy boost, receiving a median dose of 72 Gy to the nasopharynx., Results: At the initial presentation, the Chinese patients were significantly younger, less likely to smoke, more likely to have Stage IV disease, and more likely to have cancer with lymphoepithelioma histologic features. After controlling for stage, age, histologic type, and treatment variables, Chinese patients were significantly more likely to develop distant metastases (p <0.05). Although Chinese race does not predict for local control or overall survival, a younger age, continued tobacco use, total radiation dose, and lymphoepithelioma histologic features do., Conclusion: In a large retrospective analysis of nasopharyngeal carcinoma, Chinese and non-Chinese patients differed significantly in presentation-age, stage, and histologic features-and outcome. We suggest as an explanation differences in intrinsic tumor biology rather than differences in treatment techniques or staging systems. Additional trials in endemic countries are needed to confirm the optimal treatment of Chinese and Chinese-American patients.

Purpose: To retrospectively investigate whether postoperative low-pelvic radiotherapy (RT) is an appropriate treatment for node-negative, high-risk Stage I-IIA cervical cancer patients., Methods and Materials: A total of 228 Stage I-IIA cervical cancer patients treated by radical surgery and postoperative RT were included in this study. All patients had histopathologically negative pelvic node metastasis, but at least one of the following risk factors: parametrial involvement, positive or close resection margins, invasion depth two-thirds or greater cervical stromal thickness. Seventy-nine patients (35%) received 30-50 Gy (median 44) to whole pelvis and a boost dose to the low pelvis (whole-pelvic RT group); the other 149 patients (65%) received low-pelvic RT only (low-pelvic RT group). For both groups, the total external RT dose to the low pelvis ranged from 40 to 60 Gy (median 50). The potential factors associated with survival, small bowel (gastrointestinal) complications, and leg lymphedema were analyzed, and patients who had a relapse in the upper pelvis were identified., Results: The 5-year overall and disease-specific survival rate was 84% and 86%, respectively. After multivariate analysis, only bulky tumor (>or=4 cm) and non-squamous cell carcinoma were significantly associated with survival. Parametrial involvement, lymph-vascular invasion, 50.4 Gy to the low pelvis, but not old age and treatment technique (AP-PA vs. box), were significantly associated with gastrointestinal complications. Three patients (2%) in the low-pelvic RT group and 6 patients (8%) in the whole-pelvic RT group were found to have Grade III or higher small bowel complications (p = 0.023). Thirty-one percent of patients developed lymphedema of the leg. A dose to the low pelvis >50.4 Gy and an AP-PA field, but not whole-pelvic RT, old age, or the number of sampled lymph nodes, were associated with lymphedema of the leg. Five patients (3.6%) of the low-pelvic RT group and none of the whole-pelvic RT group developed upper pelvis relapse. Three of these 5 patients had upper pelvic relapse alone., Conclusion: Compared with whole-pelvic RT plus low-pelvic boost, low-pelvic RT alone significantly reduces the small bowel complications in node-negative, high-risk, Stage I-IIA cervical cancer patients. Although low-pelvic RT alone increases the incidence of upper pelvic relapse, its effect on survival is not substantial. Low-pelvic RT alone appears to be an appropriate treatment method for this group of patients.

Purpose: To evaluate the clinical features of isolated paraaortic lymph node (PALN) recurrence after definitive radiotherapy, and analyze the prognostic factors and effect of salvage treatment., Methods and Materials: Of a total 876 patients who received pelvic radiotherapy after the diagnosis of primary cervical carcinoma, 26 were found to have isolated PALN recurrence as the first recurrent site, and these patients enrolled in this study. Only those with primary-site carcinoma controlled and who were free of other distant metastases were eligible. Nineteen of the 26 patients accepted salvage therapy. Fourteen patients accepted concurrent chemoradiation (CCRT), 1 accepted radiation to the paraaortic region, and 4 accepted chemotherapy alone. Clinical parameters evaluated included tumor markers (SCC and CEA) and image studies., Results: Seven of the 26 patients were alive and disease-free. All 7 survivors had salvage treatment with radiation to the paraaortic region and concurrent cisplatin-based chemotherapy. None of the patients receiving chemotherapy or radiation alone enjoyed long-term, disease-free survival. The 5-year survival rate for isolated PALN recurrence of the 14 patients who accepted salvage concurrent chemoradiation (CCRT) was 51.2%. The presence of a clinical symptom at the time of PALN recurrence was analyzed. Seven of the 12 asymptomatic patients and none of the 14 symptomatic patients survived without disease after salvage treatment. The SCC levels at recurrence showed a statistically significant relationship to disease-free survival., Conclusions: An SCC level of < or = 4 ng/ml and a lack of symptoms at the time of recurrence were good prognostic factors in isolated PALN recurrence after primary radiation therapy. In addition to concurrent CCRT, periodical surveillance with tumor markers and imaging studies allowed early detection and salvage of those patients.

Purpose: To evaluate our policy of performing neck dissection based on regional response after definitive radiotherapy in patients with supraglottic carcinoma and to identify the prognostic factors in this group of patients., Methods and Materials: Between 1970 and 1995, 121 patients with node-positive squamous cell carcinoma of the supraglottic larynx were treated with definitive radiotherapy. Sixty-nine percent of patients presented with 1997 AJCC Stage IV disease. The N-stage distribution was N1, 49; N2, 62; and N3, 10. The median size of the lymph nodes was 3 cm (range, 0.5-8 cm). Forty-five patients received once-a-day treatment with a median total dose of 65 Gy (range, 58.0-70.8 Gy) in 1.8-2.0 Gy per fraction over 48 days, and 76 patients received split-course accelerated hyperfractionation with a median total dose of 67.2 Gy (range, 63.2-73.6 Gy) in 1.6 Gy twice a day over 43 days. Patients whose lymph nodes were not clinically detectable at 4-6 weeks after the completion of radiotherapy (complete response) were followed without any neck dissection. Patients with persistent neck adenopathy (partial response) underwent neck dissection whenever possible. Mean follow-up of the living patients was 6.5 years., Results: Regional response was related to the size of lymph nodes at presentation. Eighty-seven percent of patients with nodal size of 3 cm or less had a complete response, whereas 43% of patients with nodal size greater than 3 cm had a partial response. The rate of regional control at 3 years for all patients in the study was 66%. The 3-year ultimate regional control rate after salvage neck dissection was 75%. A relapse in both the primary and regional sites was the most common pattern of relapse, accounting for 39% of all the failures. Local failure was associated with subsequent regional relapse with a relative risk of 4.3. For patients with complete response in whom postradiotherapy neck dissection was withheld, the regional control rates were 75% and 86% for N1 and N2, respectively. The rate of isolated regional relapse in this group of patients was 7.5%. In multivariate analysis, significant favorable factors predictive for regional control were female gender, accelerated hyperfractionation, and complete response; whereas factors predictive for overall survival were Karnofsky Performance Scale score and regional response. The rate of Radiation Therapy Oncology Group (RTOG) Grade 2 or 3 neck fibrosis was 17% and 23% for patients with and without postradiotherapy neck dissection, respectively., Conclusion: Isolated regional relapse is not common in patients with supraglottic carcinoma when a complete response is achieved at 4-6 weeks after definitive radiotherapy and postradiotherapy neck dissection is not performed. Female gender, accelerated hyperfractionation, and complete response are favorable predictors of regional control.

Purpose: To investigate the prognostic significance of the pre- and posttreatment serum squamous cell carcinoma antigen (SCC) levels in patients with Stage I-IVA squamous cell carcinoma of the cervix primarily treated by radiotherapy., Materials and Methods: 401 patients with squamous cell carcinoma of cervix primarily treated with radiotherapy (RT) were included in this study. All had preRT, and 249 patients had postRT serum SCC values. The association of pretreatment SCC level with the clinical parameters, including stage, hemoglobin (Hb) level, age, cell differentiation, and lymph node status, was assessed by univariate and multivariate analysis. The prognostic significance of pretreatment SCC level and these clinical parameters were evaluated. The impact of postRT residual induration and SCC levels on survival was analyzed., Results: 1. PreRT SCC level strongly correlated with stage. After controlling for stage, only SCC levels higher than 10 ng/ml were associated with enlarged lymph nodes shown in CT scan. No association of preRT SCC level with other clinical parameters was found. 2. SCC level higher than 10 ng/ml, but not between 2-10 ng/ml, had significant impact on survival in a multivariate analysis. Stage, Hb levels (<10 g/dl) and positive lymph node shown by CT scan were also independent prognostic factors for survival. No significant difference in failure pattern in terms of local and/or distant sites was found in patients with different SCC levels. 3. Patients with residual induration and/or persistently elevated SCC level at 2-3 months after RT had a significantly higher incidence of treatment failure. Persistently elevated SCC level is a stronger predictor for treatment failure than residual induration by pelvic examination, and is associated with a higher incidence of distant metastasis. One third of patients with initial SCC level higher than 10 ng/ml had persistently elevated SCC., Conclusion: Pretreatment SCC levels higher than 10 ng/ml are an independent predictor for poor prognosis in patients included in this study, and can be used as one of the prognostic factors for selection of patients for intensive treatment. Persistently elevated SCC levels after RT is a strong predictor for treatment failure. A combination of clinical pelvic examination and SCC levels provides useful information for the need of further work-up and management.

Purpose: To present the treatment results and assess the optimal radiation dose and the role of brachytherapy in early stage nasopharyngeal cancer (NPC)., Methods and Materials: One hundred eighty-three patients with Stage I and II (American Joint Committee on Cancer Staging System, 1987) NPC completed the planned radiotherapy in our institution from 1979 to 1991. In 133 patients, radiotherapy was given to the nasopharynx by external beam to 64.8-68.4 Gy. Further boost was done by high dose rate (HDR) brachytherapy for 5-16.5 Gy in one to three fractions. For the remaining 50 patients, a course of external radiotherapy to the nasopharynx for 68.4-72 Gy was given to nasopharynx. Age (>40 or not), sex, neck boost or not, brachytherapy, and irradiation dose were analyzed to determine significant factors that influence the probabilities of local control and actuarial survival., Results: The 5-year disease-specific survival was 85.8% and local control was 83%. Only the brachytherapy and irradiation dose significantly affected the results. The use of the brachytherapy had significant impact on overall survival and local control. Furthermore, we compared the prognostic effect of various radiation dosage among Group I of 50 patients (<72.5 Gy, no brachytherapy, excluding four patients who received brachytherapy), Group II of 71 patients (72.5-75 Gy; one to two fractions of brachytherapy), and Group III of 58 patients (>75 Gy; three fractions of brachytherapy). Five-year disease-specific survival rates of Group I, Group II, and Group III were 77, 95.5, and 82.4%, respectively. Five-year local control rates were: 73.7, 93.9, and 79.5%. We found that the Group II had the best actuarial survival and local control rate (log-rank test,p < 0.05). Most patients receiving brachytherapy encountered foul odor because of nasopharynx crust; 12 of them had palate or sphenoid sinus floor perforation or nasopharynx necrosis. None of the patients without brachytherapy experienced the same complications., Conclusions: The optimal radiotherapy dose to the nasopharynx area in early stage NPC may be within 72.5 to 75 Gy by our treatment protocol. A dose of more than 75 Gy did not have significant local control or survival advantage. The use of brachytherapy to elevate radiation dose had significant local control and survival benefit for early stage NPC patients, but the fractionation size should be decreased to reduce the complications.

Purpose: To study the effects of midcourse treatment break or gaps related to the local control of T3 carcinoma of the oropharynx and larynx following accelerated hyperfractionated radiation therapy., Methods and Materials: All patients were treated at the Massachusetts General Hospital from 1979 through 1994 with treatment consisting of 1.6 Gy per traction, two fractions a day for the treatment of T3 carcinoma of the oropharynx and larynx. They were entered in the head and neck data base. Their treatment dates, treatment breaks, and doses vs. local control were analyzed and compared. A p-value of 0.05 was considered statistically significant., Results: A total of 162 patients were available for review. Due to the acute severe mucosal effects, most of the patients required a midcourse pause or "break" after a dose of 38.4-48 Gy before treatment could be resumed and completed. The data indicate that (a) prolongation of the treatment gap for more than 14 days, (b) total treatment course longer than 45 days, (c) total dose less than 67 Gy, and (d) male gender adversely affected local control. In spite of the gaps, the female patients with advanced carcinomas enjoyed the benefits of improved local control after the accelerated hyperfractionated radiation therapy., Conclusions: Accelerated hyperfractionation radiation therapy using 1.6 Gy per fraction/twice-a-day (b.i.d.) for a total dose of 70.4 Gy in 6 weeks is effective in achieving high local control of T3 squamous cell carcinoma of the oropharynx and larynx. The midcourse treatment gap should be as short as possible with the projected total dose and time. Should the gaps be unduly prolonged due to various circumstances, further increase in the total dose, for example, 72-75 Gy, and/or increase of the fraction sizes, for example, 1.8-2.0 Gy/f b.i.d. after the gap may be necessary to compensate for the adverse effects of the tumor regeneration from the prolonged gap.

Purpose: To analyze our experience treating soft tissue sarcomas of the head and neck in adults, and to identify patterns of failure and prognostic factors., Methods and Materials: The records of 57 patients with Stage M0 disease treated by radiation with or without surgery between 1972 and 1993 were reviewed. Median follow-up time was 4.3 years (range, 1.1-16.8 years). A group of potential prognostic factors was evaluated, including age at diagnosis, sex, initial tumor presentation (primary vs. recurrent), grade, T-stage, direct tumor extension, tumor depth, duration of treatment, and radiation dose., Results: The subset of angiosarcomas (11 out of 57 patients) had a considerably adverse effect on treatment outcome for the total group of sarcomas, with actuarial 5-year overall survival (OS), locoregional control (LRC), and freedom from distant metastasis (FDM) rates being 31%, 24%, and 42%, respectively. In contrast, for the remaining 46 patients with other histopathological tumor types, OS, LRC, and FDM rates were significantly higher (74%, 69%, and 83%, respectively). For this group of patients, significant prognostic factors identified by uni- and multivariate analysis included tumor grade as a predictor of OS and T-stage as a predictor of LRC (p < or = 0.050). Those patients who experienced a locoregional recurrence were at a significantly increased risk of dying (p = 0.004 in a multivariate model). All 17 patients without direct tumor extension to neurovascular structures, bone, contiguous organs, or skin remained free from distant failure. In contrast, 27% of 29 patients with direct extension had developed distant metastases at 5 years. In multivariate analysis, the absence of direct extension was a positive predictor of FDM (p = 0.007) and of OS (p = 0.034)., Conclusions: 1) Angiosarcomas of the head and neck have a considerably poorer prognosis than other soft tissue sarcomas of this site. 2) In addition to tumor grade and size, direct tumor extension may be a useful additional staging parameter. 3) High rates of locoregional failure in the head and neck area, a potential cause of morbidity and death, indicate a need for improved treatment strategies.

Purpose: The purpose of this paper is to present local control rates of carcinoma of the larynx in relation to the total treatment course after radical radiation therapy., Methods and Materials: A total of 1350 patients with laryngeal carcinoma treated at the Massachusetts General Hospital for the past three decades were available for analysis. Treatment courses were divided into two groups: 45 days and > 45 days. The local control rates were compared and evaluated for statistical differences., Results: The data indicated that prolonged treatment course adversely affects local tumor control of both advanced glottic and supraglottic lesions, but to a lesser degree for the early tumors., Conclusion: The study indicated that for optimal local control, radiation treatment should be completed as soon as possible, preferably within 6.5 weeks, either by once- or twice-daily accelerated programs. The local control of early T1 glottic cancer has been exceedingly satisfactory by conventional once-daily radiation therapy. Further improvement by shortening of treatment time for such early lesions will be difficult to assess without a prospective randomized trial.

Purpose: Occasionally in the long-term survivors of early carcinoma of the larynx, following radiation therapy a second carcinoma may arise from the previously irradiated larynx. Traditionally, management of such lesions is by non-radiation means in the belief that a further full course of radiation therapy is not possible and may exceed the tolerance of the normal laryngeal structures. Unfortunately, surgical treatment of the second carcinoma is often either total or partial laryngectomy which may not be acceptable to the patients and therefore radiation therapy is used as an alternative., Methods and Materials: This paper presents our experience in re-irradiation of laryngeal carcinomas arising from the previously irradiated larynx. As of October 1992 a total of 20 patients were available for evaluation. Most patients had Stage I and II laryngeal carcinoma and received high doses of re-irradiation ranging from 60 to 70 Gy either by conventional or accelerated hyperfractionation schemes., Results: The 5-year actuarial local control and survival rates were 60 to 93%, respectively. The majority of the survivors had relatively normal and functional larynges. Those who failed locally had total laryngectomy without significant postoperative complications., Conclusion: With this information the radiation tolerance of laryngeal structures is found to be much higher than commonly believed and re-irradiation for early carcinoma of the larynx is possible and proved to be a useful alternative to surgery and laryngectomy is therefore reserved for failure. The techniques of re-irradiation will be discussed.

Purpose: Locally advanced inverted papilloma and inverted papilloma associated with squamous cell carcinoma are at high risk of local failure due to limitations of surgical resection resulting in repeat surgical procedures. The role of adjuvant radiation therapy is poorly defined. This study reviews a single institution experience of radiation therapy in the management of this disease., Methods and Material: Between 1977 and 1990 25 patients were treated at the Massachusetts General Hospital and the Massachusetts Eye and Ear Infirmary with radiation therapy for inverted papilloma (seven patients) and inverted papilloma associated with squamous cell carcinoma (18 patients) of the nasal cavity and paranasal sinuses. All patients presented with locally advanced invasive tumors; 5 of 7 with inverted papilloma had previous resections and 4 of 18 with associated squamous cell carcinoma had history of prior surgical excisions of inverted papilloma only (three patients) or inverted papilloma with squamous cell carcinoma in situ (one patient). Sixteen patients underwent radiation treatment following gross total resection, eight patients after subtotal tumor resection and one patient was inoperable by local invasion and received radiation therapy alone., Results: Local control was achieved in 6 of 7 patients with inverted papilloma only and one patient required additional resection for persistent disease. Of 18 patients with associated squamous cell carcinoma, 17 were locally controlled after radiation therapy and one had persistent tumor. One patient failed locally 3 years after treatment. With a mean observation time of 4.8 years (range: 0.5-12.9 years) all seven (100%) patients with inverted papilloma only and 15 of 18 (83%) patients with associated invasive carcinoma are alive and without evidence of disease. Three patients with inverted papilloma associated with squamous cell carcinoma died, two patients as a result of their disease (one patient with persistent disease, one patient after local failure) and one patient of intercurrent disease. No failure in either regional lymph nodes or at distant sites was recorded. In the majority of cases radiation therapy was well-tolerated., Conclusions: Combined radiation therapy and surgery can offer excellent long-term control and should be considered in patients with history of recurrent disease, in the presence of suspected residual disease, after incomplete resection or for unresectable lesions. Patients with associated squamous cell carcinoma have a more aggressive course, however radiation therapy still has the prospect of permanent disease-free survival in patients who achieve local control.

This paper presents our experience and the local control rates of a group of patients with inoperable and unresectable lesions treated by photon irradiation from 1980 through 1989. The patient material consists of a total of 24 patients, 9 with carcinoma arising from the parotid gland and 15 with lesions in the minor salivary glands, mainly the oral cavity and oropharynx. The pathologic slides were reviewed and malignancy of various cell types confirmed. The 5-year actuarial local control of parotid gland lesions after photon irradiation was 100% and the survival rate was 65%. For the minor salivary gland lesions, the 5-year actuarial local control was 78% and the survival rate with or without disease was 93%. All lesions were irradiated by accelerated hyperfractionated photons (bid) with 1.6 Gy per fraction, intermixed with various boost techniques including electron beam, intraoral cone, interstitial implant, and/or submental photons for a total of 65-70 Gy. Most treatment failures of parotid cancer were due to distant metastases. The present series showed excellent local control and satisfactory survival of inoperable and unresectable salivary gland carcinomas after state-of-the-art photon irradiation, comparable to that achieved by neutron irradiation. The late complications were minimal. A controlled randomized trial may be indicated.

Lymphoma of the conjunctiva is rare. It presents in older patients as a mass lesion and usually remains localized. Surgery is limited to biopsy, and radiation therapy is the definitive treatment of choice. The entire conjunctiva is treated. Relatively high doses (approximately 30 Gy) are required for local control, which may lead to cataract formation. Twelve patients with conjunctival lymphoma were treated at the Massachusetts General Hospital between 1979 and 1988. Ten of 12 patients presented with a unilateral lesion; 2 of 12 with bilateral lesions. Two of 12 patients were found to have systemic disease at the time of presentation. One patient developed conjunctival lymphoma 5 years after the diagnosis of generalized disease. Using electron beam, all patients were treated with a single anterior circular field to total doses ranging from 24 Gy to 30 Gy delivered in 8 to 16 fractions over 9 to 20 days. In all cases, the lens was shielded by a specially designed plastic contact lens bearing a 12 mm diameter lead shield. The lens dose was determined at varying depths beneath the shield for 6 MeV and 9 MeV electron beams and ranged from a minimum of 5% to an absolute maximum of 18% of the total dose delivered to the tumor. Local control was maintained in all patients with follow-up to 9 1/2 years. One patient relapsed distantly 3 years after treatment. One of 12 patients died of systemic disease 4 years after treatment of the ocular lesion. Two patients developed cataracts 4 and 5 years after treatment; one had bilateral cataract, although only one eye had been treated. Both patients were over 75 years old. In both cases, the cataracts were felt to be senile cataracts which are ophthalmologically and radiographically distinguishable from radiation induced lesions.

In October 1979 we started an accelerated hyperfractionation program consisting of 1.6 Gy/fraction, 2 fractions/day for 12 days or 38.4 Gy. Due to acute toxicity, the patients were then given a 2-week break and resumed once daily radiation therapy with 1.8 Gy/fraction up to 65 Gy, designated as the b.i.d.-q.d. program. In August 1982, the program was changed and the latter part of the treatment was continued on the twice daily program with 1.6 Gy/fraction for a total of 64 Gy, designated as the b.i.d.-b.i.d. program. We evaluated the local control rates of 140 patients with squamous cell carcinomas arising from the oropharynx, that is faucial tonsil and base of tongue. After these treatment regimens, the 36 month actuarial local rates for the T1-4 lesions were 56% for b.i.d.-q.d. (52 patients) and 85% for b.i.d.-b.i.d. (88 patients) with a p value of 0.0013. For the T1-2 lesions the corresponding rates were 81% (13 patients) and 97% (44 patients) with a p value of 0.53. The difference was marked for the T3-4 lesions, that is 47% vs 77% respectively with a p value of 0.017, and those patients without nodal metastases, that is 46% vs 93% with a p value of 0.00043. The improvement was probably due to marked shortening of the overall treatment course following b.i.d.-b.i.d. accelerated program--in this case 1 1/2 weeks. Our preliminary data suggests that the b.i.d.-b.i.d. program is superior to the b.i.d.-q.d. program. The seemingly improved local control rates for the treatment of oropharyngeal carcinomas requires a clinical prospectively randomized trial for confirmation, that is b.i.d.-b.i.d. versus b.i.d.-q.d. versus standard fractionation (q.d.) program.

A total of 30 patients with histologically confirmed sebaceous carcinoma of the ocular adnexa were evaluated at our institution from 1974-1986. There were 18 women and 12 men in the series with a median age of 61 years. Ten cases received radiotherapy with curative intent. Four patients were treated definitively with doses ranging from 45-63.0 Gy over 4-7 weeks. Six patients received post-operative radiotherapy to the parotid bed and ipsilateral cervical lymph node chain for parotid metastases developing within 36 months of initial surgical treatment. Patients with lower lid lesions and significant pagetoid histologic components were more likely to develop parotid lymph node metastases. Local control at the primary site after radiation and/or surgery was 90% with follow-up ranging from 2-10 years. Overall disease specific actuarial survival at 5 years was 96%. Radiation therapy is an effective treatment modality in adnexal sebaceous carcinoma. With employment of careful technique and state-of-the-art technology, long term local control and survival with satisfactory cosmetic and functional results can be anticipated.

With an increasing number of high energy accelerators in operation, intra-oral electron radiotherapy is likely to become a more widely-used modality in the treatment of lesions of the oral cavity. However, there is one potential problem associated with this modality which concerns patient safety. There must never be any uncontrolled movement of the couch or gantry while the cone is in the patient's mouth, otherwise serious consequences could occur. In an effort to overcome this problem, a set of cones previously constructed by us for use in intra-oral electron radiotherapy has been modified to include a breakaway safety feature. This modification consists of separating the plate into which each of the treatment cones screws, into two pieces, the dividing line being in the shape of a cone frustum flaring out in the upward direction. A set of four spring plungers projecting into a notch on the inner ring prevents the cone from being pushed upwards without the application of an upward force. The amount of force required to push the cone upwards can be changed by adjusting the pressure of the spring plungers.

The employment of a 10 MV X ray beam for treatment of head and neck tumors has been investigated. A 1.2 cm thick beam spoiler positioned 7 cm from the patient surface was used to achieve adequate dose to the superficial region. This technique provides at least 90% depth dose at 0.5 cm depth, which is clinically required for the treatment. For departments able to acquire only one megavoltage machine, the technique can provide an option to treat adequately both shallow as well as deep-seated tumors by choosing a high megavoltage machine; a low megavoltage machine cannot provide an equivalent option to treat deep-seated tumors.

A set of intra-oral cones has been constructed for electron beam therapy from a linear accelerator. We have modified the 4 cm X 4 cm treatment accessory provided with this machine by simply removing the lower collimator and replacing it with a brass plate into which all the cones can fit, so that they are easily interchangeable. Six circular cones, with diameters ranging from 27 mm and to 45 mm, plus two elliptical cones are currently in use. A light field system has been built that fits into the acrylic compartment directly above the base, and provides a clear, well-illuminated view of the treatment field. The dosimetry for these cones shows that the percent depth dose curve for a 41 mm diameter field is the same as that obtained with the 4 cm X 4 cm treatment accessory, and that the isodose curves are very similar. This intra-oral cone system has been in operation for over two years and we have found it very useful in boosting the dose to specific primary lesions in the oral cavity, for example, oral tongue, floor of mouth, retromolar trigone, and soft palate.

An afterloading vaginal applicator has been built that incorporates two ovoid sources and two tandem sources arranged in the shape of a T, the tandems forming the upright and the ovoids, orthogonal to the tandems, located at the ends of the crossbar. The body of the applicator was designed and constructed to correspond to the 90 cGy/hr contour for a source loading of 10 mg Ra Eq 137Cs for the ovoids and 15 mg Ra Eq 137Cs for the tandems. TLD measurements made at various points located around the applicator in the AP and lateral planes indicate agreement with the dose calculated by computer to within +/- 1%.

We report the radiation therapy of keratoacanthoma in 13 patients using orthovoltage X rays and electrons. All patients had an excellent cosmetic result, and time to regression was dose dependent up to a dose corresponding to TDF 50; increasing dose beyond this level did not accelerate time to regression past 2.4 months. We also note a heretofore undocumented association between keratoacanthoma and second malignancy.