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Purpose To update brachytherapy recommendations for pretreatment evaluation, treatment, and dosimetric issues for thoracic brachytherapy for lung cancer. Methods and Materials Members of the American Brachytherapy Society with expertise in thoracic brachytherapy updated recommendations for thoracic brachytherapy based on literature review and clinical experience. Results The American Brachytherapy Society consensus guidelines recommend the use of endobronchial brachytherapy for disease palliation in patients with central obstructing lesions, particularly in patients who have previously received external beam radiotherapy. The use of interstitial implants after incomplete resection may improve outcomes and provide enhanced palliation. Early reports support the use of CT-guided intratumoral volume implants within clinical studies. The use of brachytherapy routinely after sublobar resection is not generally recommended, unless within the confines of a clinical trial or a registry. Conclusions American Brachytherapy Society recommendations for thoracic brachytherapy are provided. Practitioners are encouraged to follow these guidelines and to develop further clinical trials to examine this treatment modality to increase the evidence base for its use.

Purpose The aim of this study was to define current patterns of care among radiation oncologists who use skin surface brachytherapy for the treatment of cutaneous squamous cell carcinoma (cSCC) and basal cell carcinoma (BCC) in academic and community settings. Methods and Materials A 30-question electronic survey was administered to clinician members of the American Brachytherapy Society. The respondents were asked to provide details regarding their clinical practice and their approach to skin surface brachytherapy. Results A total of 16 surveys were returned. Among the respondents, aggregate experience varied from 8 to 1800 cases. Most preferred brachytherapy over external beam radiation because of shorter treatment course, conformality of treatment for irregular or curved targets, and shallow dose deposition. Of the total, 60% of respondents routinely estimated lesion depth via ultrasound before initiating treatment. Treatment margin on gross disease varied widely (range, 3–15 mm; median, 5 mm). Hypofractionation was the preferred dose schedule. Prescribed doses ranged from 30 Gy in five fractions to 64 Gy in 32 fractions (EQD2, 40 Gy–65 Gy). There was a tendency to increase the number of fractions for larger targets, although some used the same fractionation regardless of anatomic location or lesion size. There was no consensus on dosimetric constraints, and some respondents reported cases of severe toxicity, particularly when treating the pretibial skin. Conclusions This pattern of care study suggests that skin brachytherapy can be a convenient and safe tool for treatment of BCC and cSCC. Prospective trials and the development of expert consensus guidelines would be beneficial for optimizing skin surface brachytherapy and reducing practice variation.

Intensity-modulated radiation therapy (IMRT) has been applied for treatments of primary head with neck nodes, lung with supraclavicular nodes, and high-risk prostate cancer with pelvis wall nodes, all of which require large fields. However, the design of the Varian multileaf collimator requires fields >14 cm in width to be split into 2 or more carriage movements. With the split-field technique, both the number of monitor units (MUs) and total treatment time are significantly increased. Although many different approaches have been investigated to reduce the MU, including introducing new leaf segmentation algorithms, none have resulted in widespread success. In addition, for most clinics, writing such algorithms is not a feasible solution, particularly with commercial treatment planning systems. We introduce a new approach that can minimize the number of split fields and reduce the total MUs, thereby reducing treatment time. The technique is demonstrated on the Eclipse planning system V7.3, but could be generalized to any other system.

Purpose To assess toxicity and outcome following permanent iodine-125 seed implant as an adjunct to surgical resection in cases of advanced thoracic malignancy. Methods and Materials An institutional review board-approved retrospective review was performed. Fifty-nine patients were identified as having undergone thoracic brachytherapy seed implantation between September 1999 and December 2006. Data for patient demographics, tumor details, and morbidity and mortality were recorded. Results Fifty-nine patients received 64 implants. At a median follow-up of 17 months, 1-year and 2-year Kaplan-Meier rates of estimated overall survival were 94.1% and 82.0%, respectively. The 1-year and 2-year local control rates were 80.1% and 67.4%, respectively. The median time to develop local recurrence was 11 months. Grades 3 and 4 toxicity rates were 12% at 1 year. Conclusions This review shows relatively low toxicity for interstitial planar seed implantation after thoracic surgical resection. The high local control results suggest that an incomplete oncologic surgery plus a brachytherapy implant for treating advanced thoracic malignancy merit further investigation.

After breast-conserving surgery, a seroma often forms in the surgical cavity. If not drained, it may affect the volume of tumor bed requiring a boost after whole-breast radiation therapy (WBRT). Our objective was to evaluate the change in seroma volume that occurs during WBRT, before boost planning.A retrospective review was performed of women receiving breast-conserving therapy with evidence of seroma at the time of WBRT planning. Computed tomography (CT) simulation was performed before WBRT and before the tumor bed boost. All patients received either a hypofractionated (42.4 Gy/16 fraction + 9.6 Gy/4 fraction boost) or standard fractionated (50.4 Gy/28 fraction + 10 Gy/5 fraction boost) regimen. Seroma volumes were contoured and compared on CT at the time of WBRT simulation and tumor bed boost planning.Twenty-four patients with evidence of seroma were identified and all patients received WBRT without drainage of the seroma. Mean seroma volume before WBRT and at boost planning were significantly different at 65.7 cm(3) (SD, 50.5 cm(3)) and 35.6 cm(3) (SD, 24.8 cm(3)), respectively (p0.001). Mean and median reduction in seroma volume during radiation were 39.6% (SD, 23.8%) and 46.2% (range, 10.7-76.7%), respectively. Fractionation schedule was not correlated with change in seroma volume. Length of time from surgery to start of radiation therapy showed an inverse correlation with change in seroma volume (Pearson correlation r = -0.53, p0.01).The volume of seroma changes significantly during WBRT. Consequently, the accuracy of breast boost planning is likely affected, as is the volume of normal breast tissue irradiated. CT-based boost planning before boost irradiation is suggested to ensure appropriate coverage.

Placement of the MammoSite® breast brachytherapy catheter is most commonly performed either intraoperatively or under ultrasound-guided technique. Below, we present a case report of an alternate approach utilizing CT-scan guidance. This is the first reported case of a balloon brachytherapy catheter placement with this technique.

Purpose This review examines the role of permanent radioactive seed implantation in thoracic malignancy. This technique can be used intraoperatively to provide additional highly localized radiation therapy in cases where optimal oncologic margins are unattainable or to palliate unresectable disease. Methods and materials Relevant trials were identified through a systematic literature search using Pubmed. Results The intraoperative placement of brachytherapy seeds has been described after sublobar resection for non–small-cell lung cancer (NSCLC), where surgical margins are close or microscopically positive and in the presence of macroscopic residual disease. This brachytherapy technique is currently the focus of a randomized prospective trial in the USA in patients unfit for lobectomy for early-stage NSCLC. Conclusions This review summarizes the methods of brachytherapy seed placement and the published experience of brachytherapy implants within the thorax, also examining radiation safety and postoperative dosimetry. This technique has the potential to improve local control with optimal sparing of normal tissue owing to its highly conformal radiotherapy delivery.

Background and Purpose IMRT clinical trials lack dose prescription and specification standards similar to ICRU standards for two- and three-dimensional external beam planning. In this study, we analyzed dose distributions for patients whose treatment plans incorporated IMRT, and compared the dose determined at the ICRU reference point to the PTV doses determined from dose–volume histograms. Additionally, we evaluated if ICRU reference type single-point dose prescriptions are suitable for IMRT dose prescriptions. Materials and methods For this study, IMRT plans of 117 patients treated at our institution were randomly selected and analyzed. The treatment plans were clinically applied to the following disease sites: abdominal (11), anal (10), brain (11), gynecological (15), head and neck (25), lung (15), male pelvis (10) and prostate (20). The ICRU reference point was located in each treatment plan following ICRU Report 50 guidelines. The reference point was placed in the central part of the PTV and at or near the isocenter. In each case, the dose was calculated and recorded to this point. For each patient – volume and dose (PTV, PTV mean, median and modal) information was extracted from the planned dose–volume histogram. Results The ICRU reference dose vs PTV mean dose relationship in IMRT exhibited a weak positive association (Pearson correlation coefficient 0.63). In approximately 65% of the cases studied, dose at the ICRU reference point was greater than the corresponding PTV mean dose. The dose difference between ICRU reference and PTV mean doses was ⩽2% in approximately 79% of the cases studied (average 1.21% (±1.55), range −4% to +4%). Paired t-test analyses showed that the ICRU reference doses and PTV median doses were statistically similar (p = 0.42). The magnitude of PTV did not influence the difference between ICRU reference and PTV mean doses. Conclusions The general relationship between ICRU reference and PTV mean doses in IMRT is similar to that in 3D CRT distributions. Point doses in IMRT are influenced by the degree of intensity modulation as well as calculation grid size utilized. Although the ICRU reference point type prescriptions conceptually may be extended for IMRT dose prescriptions and used as a representative of tumor dose, new universally acceptable dose prescription and specification standards for IMRT based on RTOG IMRT prescription model incorporating dose–volume specification would likely lead to greater consistency among treatment centers.

Purpose We correlated rectal and bladder point and volumetric dose data in patients treated for advanced cervix cancers with combined intracavitary-interstitial high-dose-rate (HDR) brachytherapy (BT). The results are compared with published Vienna applicator data. Methods and Materials We retrospectively analyzed 30 individual combined intracavitary plus interstitial implants from 10 patients treated with external beam radiation therapy (EBRT) followed by HDR BT for locally advanced cervix carcinoma. EBRT consisted of 45 Gy to the pelvis followed by 9–14.4 Gy boost to involved parametria. BT consisted of a total dose of 21 Gy delivered in 7 Gy fraction. For each implant, CT-image-based simulation and image-guided BT treatment planning was performed. Bladder and rectal doses were evaluated and analyzed using both International commission on Radiation Units and Measurements (ICRU) reference points and dose–volume histograms. The cumulative doses to the rectum and bladder were calculated by combining contributions from external beam therapy and BT. To facilitate comparison with published literature, the total doses were normalized to equivalent dose in 2-Gy fractions (EQD 2 ) using the equation EQD 2total = EQD 2EBRT + EQD 2BT . Results For the patient population considered, the mean ICRU bladder dose was 75 (±4) Gy 3 compared to bladder D 0.1 cc and D 2 cc doses of 84 (±4) and 78 (±3) Gy 3 , respectively. The mean ICRU rectal dose was 73 (±4) Gy 3 compared to rectal D 0.1 cc and D 2 cc doses of 79 (±5) and 74 (±4) Gy 3 , respectively. For rectum, the mean dose ratios ( D 0.1 cc / D ICRU ) and ( D 2 cc / D ICRU ) were 1.08 and 1.01, respectively, compared to Vienna applicator study mean dose ratios of 1.08 and 0.93, respectively. ICRU rectal dose correlated with volumetric rectal doses and best with volumetric D 2 cc dose ( r S = 0.91, p = 0.0003); however, ICRU bladder dose did not correlate with volumetric bladder dose. Conclusions Our study findings reveal a strong correlation between ICRU rectal reference dose and volumetric rectal D 2 cc dose in combined intracavitary-interstitial HDR brachytherapy. This surrogate rectal–dose relationship is valuable in establishing rectal tolerance dose levels in transitioning from traditional two-dimensional to image-based three-dimensional dose planning.

Objective. There is no standard high-dose-rate (HDR) brachytherapy dose for locally advanced cervical cancer. The objective of this study was to determine the efficacy, toxicity and clinicopathologic predictive markers affecting survival using cisplatin (CDDP) concomitant with external beam pelvic radiotherapy (EBRT) and two 9-Gy HDR insertions for the treatment of locally advanced cervical cancer. Methods. 77 consecutive patients with Stage IB2–IV cervical cancer treated with CDDP, EBRT and two 9-Gy HDR insertions were included. Kaplan–Meier methods and Cox proportional hazards models were applied for survival statistics. Results. Median age was 53. 90% had squamous cell carcinoma. Median follow-up time was 3.5 years (range 0.5–12 years). Overall 5-year progression-free survival (PFS) was 75%. Local control rate and 5-year PFS were 88% and 83%, respectively, for Stages IB2/II, and 68% and 61%, respectively, for Stages III/IV. Grade 3/4 GI symptoms were the most common acute side effects (47%). Grade 3/4 late toxicities occurred in five (6%) patients. Conclusions. HDR brachytherapy regimens consisting of two 9-Gy HDR insertions have similar efficacy and side effect profiles as other brachytherapy regimens for the treatment of cervical cancer with improved safety and patient convenience.

Ovarian cancer and fallopian tube cancer typically fail in the abdomen, along with the pelvis, making them more systemic diseases. With this consideration, effective chemotherapy has slowly replaced the use of whole abdominal radiation.

Purpose To assess the radiation dose delivered to the heart and ipsilateral lung during accelerated partial breast brachytherapy using a MammoSite™ applicator and compare to those produced by whole breast external beam radiotherapy (WBRT). Materials and methods Dosimetric analysis was conducted on patients receiving MammoSite breast brachytherapy following conservative surgery for invasive ductal carcinoma. Cardiac dose was evaluated for patients with left breast tumors with a CT scan encompassing the entire heart. Lung dose was evaluated for patients in whom the entire lung was scanned. The prescription dose of 3400 cGy was 1 cm from the balloon surface. MammoSite dosimetry was compared to simulated WBRT fields with and without radiobiological correction for the effects of dose and fractionation. Dose parameters such as the volume of the structure receiving 10 Gy or more (V10) and the dose received by 20 cc of the structure (D20), were calculated as well as the maximum and mean doses received. Results Fifteen patients were studied, five had complete lung data and six had left-sided tumors with complete cardiac data. Ipsilateral lung volumes ranged from 925–1380 cc. Cardiac volumes ranged from 337–551 cc. MammoSite resulted in a significantly lower percentage lung V30 and lung and cardiac V20 than the WBRT fields, with and without radiobiological correction. Conclusion This study gives low values for incidental radiation received by the heart and ipsilateral lung using the MammoSite applicator. The volume of heart and lung irradiated to clinically significant levels was significantly lower with the MammoSite applicator than using simulated WBRT fields of the same CT data sets. Trial registration Dana Farber Trial Registry number 03-179

Purpose Primary treatment fails in >70% of locally advanced head and neck cancer patients. Salvage therapy has a 30–40% response rate, but few long-term survivors. Intensity-modulated radiotherapy (IMRT) has recently emerged as a new modality for salvage therapy. This retrospective study evaluated our experience using every-other-week IMRT with concurrent chemotherapy. Methods and Materials Between 2001 and 2006, 41 patients underwent IMRT as repeat RT with concurrent chemotherapy. All but 6 patients received 60 Gy at 2 Gy/fraction. RT was delivered on an alternating week schedule. Results With a median follow-up time of 14 months, the overall response rate was 75.6%, with a complete response and partial response rate of 58.5% and 17.1%, respectively. The Kaplan-Meier estimate of overall survival, disease-free survival, and progression-free survival at 24 months was 48.7%, 48.1%, and 38%, respectively. Patients who underwent surgery as a part of their salvage therapy had a mean estimated survival of 30.9 months compared with 22.8 months for patients who received only chemoradiotherapy (p = 0.126). Grade 3 or 4 acute toxicities occurred in 31.7% of patients, but all had resolved within 2 months of therapy completion. No deaths occurred during treatment, except for 1 patient, who died shortly after discontinuing treatment early because of previously undiagnosed metastatic disease; 6 patients had long-term complications. Conclusions Concurrent chemotherapy with repeat radiotherapy with IMRT given every other week appears to be both well tolerated and feasible in patients treated with previous radiotherapy for recurrent head and neck cancer. IMRT represents a reasonable modality for reducing treatment-related toxicities in a repeat RT setting.

PURPOSE: Permanent implantation of I-125 seeds may be used when uninvolved surgical margins are unobtainable or close. Two cases of mediastinal carcinoid tumors with prior chemoradiation had tumors adherent to esophageal muscularis. Both underwent intraoperative permanent seed implantation and developed esophageal fistulas requiring surgical correction. METHODS AND MATERIALS: Custom permanent I-125 seed mesh implants were fashioned intraoperatively in a geometrically coherent pattern. The implants were directly sutured to the partially resected esophageal wall. The postimplant CT scans were fused with the postfistula scans to provide dosimetric information at the fistula site. Doses were calculated from time of insertion to time of fistula formation. Neither patient showed evidence of disease recurrence at the time of fistula repair. RESULTS: Patient 1 developed an esophageal-pleural fistula 83 days after seed implantation. Patient 2 developed a broncho-pleural fistula 300 days after seed implantation. CONCLUSIONS: These cases demonstrated that implantation in the setting of extensive subcarinal space dissection and partial esophageal wall resection could cause fistula formation and the need for additional surgery. The high mucosal dose, despite the relatively low activity implant, was due to lack of geometric sparing of the mucosa. We recommend that extensive subcarinal space dissection be considered a contraindication to permanent seed implantation. (c) 2007. American Brachytherapy Society. All rights reserved.

632 Background: To compare the areas of residual disease after neoadjuvant pelvic radiation with 5-FU based chemotherapy for rectal cancer using Intensity Modulated Radiation Therapy (IMRT) with simultaneous integrated boost (SIB) technique compared to 3D Conformal Radiation Therapy (3DCRT) Methods: Fourty nine (49) consecutive rectal cancer patients treated with pelvic radiation and concurrent 5-FU based chemotherapy were analyzed. We compared twenty-eight (28) patients treated on an institutional IMRT protocol versus twenty-one (21) patients treated with 3DCRT. All patients received 45-50.4 Gy to the pelvis in 3DCRT group. All patients with IMRT received 45 Gy in 25 fractions to the pelvic no des. The primary rectal tumor recieved a simultaneous integrated boost to a dose of 50 Gy in 25 fractions. IMRT planning was done with dose constraints for bladder, rectum, and small bowel and bone marrow. All patients in both groups received 5-FU based chemotherapy during radiation. Evaluation of toxicity was based on RTOG criteria. 2 patients in the 3DCRT group and 2 in IMRT group received either growth factors or blood-products transfusion and needed hospitalization during treatment secondary to acute toxicities. Results: All patients completed their prescribed course of radiation. CR rates were 5/21(23%) in 3DCRT and 4/28(25%) in the IMRT-SIB (p-value 0.74). 9/21(42%) in 3D and 19/29(65%) in the IMRT group underwent Low anterior resection according to the location of the tumor. There was no grade 4 toxicity in the IMRT-SIB group. Overall grade 2 toxicity in 3D Vs IMRT-SIB group was - GI -52% Vs 19%, GU- 8% Vs 8%, skin 42 Vs 4%, hematologic 33 Vs 47%. Overall Grade 1 toxicity in 3DCRT Vs IMRT group was- GI- 33% Vs 52%, GU 23% vs 28%, Skin 52% Vs 38%, hematologic 4% Vs 33%. Conclusions: Neoadjuvant pelvic radiation with 5 FU for rectal cancer has similar local control rates. There is less GI, skin and hematologic toxicity when delivered via IMRT-SIB versus 3DCRT. IMRT is safe and may allow dose escalation with potential probability of increased tumor response.

Objective Case report of a young woman with a rare vulvar malignancy who received treatment with a personalized multidisciplinary approach to balance management of her malignancy without compromising survival with her desire for future pregnancy. Design Case report. Setting University hospital. Patient(s) A 33-year-old woman, gravida 2, para 1-0-1-1, who had a diagnosis of synovial cell sarcoma of the vulva and who desired future fertility. Intervention(s) At multiple steps, treatment was planned to try to maximize fertility preservation without potentially affecting initial treatment, which included a radical hemivulvectomy with bilateral lymph node dissection, brachytherapy with interstitial needles (20 Gy), and external beam radiation therapy (50 Gy). Main Outcome Measure(s) Treatment and eradication of the malignancy and achievement of a successful subsequent pregnancy and live birth. Result(s) The patient had no evidence of disease for 2 years after treatment. During that time she received preconception counseling by both a perinatologist and a reproductive endocrinologist. She conceived with the use of ultrasound monitoring to time intercourse specifically with ovulation from the contralateral ovary and had an uncomplicated pregnancy with a term delivery. Conclusion(s) By using several disciplines and subspecialists, this patient received personalized treatment for a rare cancer, focused at curing her cancer and optimizing her future fertility.