Melatonin Supplementation for Cancer-Related Fatigue in Patients With Early Stage Breast Cancer Receiving Radiotherapy: A Double-Blind Placebo-Controlled Trial.

BACKGROUND: Fatigue is common in patients undergoing radiotherapy (RT) and can significantly impact quality of life. Melatonin, a safe inexpensive natural supplement, may improve symptoms and attenuate the side effects of RT. The purpose of this randomized double-blind placebo-controlled phase III trial was to assess the effects of melatonin for preventing fatigue and other symptoms in patients with breast cancer undergoing RT. METHODS: Female early stage or Ductal carcinoma in situ patients with breast cancer ≥18 years of age with Eastern Cooperative Oncology Group (ECOG) performance status <3, hemoglobin ≥9 g/dL, planned for outpatient RT treatment with curative intent, were randomized 1:1 to melatonin 20 mg or placebo, orally, starting the night before RT initiation until 2 weeks post-RT. Randomization was stratified according to treatment duration (<3 weeks, ≥3 weeks) and prior chemotherapy. The primary endpoint was the Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-Fatigue scale), and secondary endpoints were FACIT-F subscales, Edmonton Symptom Assessment Scale (ESAS), and Patient-Reported Outcomes Measurement Information System (PROMIS) scores obtained at baseline, and 2 and 8 weeks post-RT. A 2-sided ANOVA F-test at a 4.5% significance level for the primary endpoint was used. Secondary analyses were reported using an F-test at a 5% significance level. The goal was to recruit approximately 140 patients with interim analysis planned mid-recruitment. RESULTS: Eighty-five patients were screened for eligibility; 79 patients were randomized: 40 to melatonin and 39 to placebo; 78 patients were treated and included in the interim analysis at the mid-recruitment point. Baseline patient characteristics of age, race, and ECOG performance status were similar in both arms. The treatment effect was studied using a longitudinal mixed effects model with the effect of treatment over time (treatment × time) as the primary outcome parameter. The treatment × time for FACIT-Fatigue did not demonstrate statistical significance (P-value .83) in the melatonin group compared to placebo. In addition, secondary analyses of FACIT physical, social, emotional, and functional well-being scores did not demonstrate statistical significance (P-values of .35, .06, .62, and .71, respectively). Total PROMIS scores, collected as secondary outcome reported by patients, did not demonstrate statistically significant change over time either (P-value is .34). The other secondary scale, ESAS, was analyzed for each individual item and found to be nonsignificant, anxiety (P = .56), well-being (.82), drowsiness (.83), lack of appetite (.35), nausea (.79), pain (.50), shortness of breath (.77), sleep (.45), and tiredness (.56). Depression was the only item demonstrating statistical significance with a decrease of 0.01 unit in the placebo group, a change not considered clinically significant. Melatonin was well-tolerated with no grade 3 or 4 adverse events reported. The most common side effects were headache, somnolence, and abdominal pain. No patients died while participating in this study. Two patients died within a year of study completion from breast cancer recurrence. Sixteen patients withdrew prior to study completion for various reasons including adverse events, hospitalizations unrelated to study drug, RT discontinuation, and COVID-19 precautions. CONCLUSIONS: In this double-blind placebo-controlled phase III trial, melatonin did not prevent or significantly improve fatigue and other symptoms in patients with early stage breast cancer undergoing RT. The analysis, showing little evidence of an effect, at mid-recruitment, assured early termination of the trial.

Outcomes with Partial Breast Irradiation vs. Whole Breast Irradiation: a Meta-Analysis.

BACKGROUND: Several randomized trials have been performed comparing partial breast irradiation (PBI) and whole breast irradiation (WBI) though controversy remains, including regarding differences by PBI technique. We performed a meta-analysis to compare results between WBI versus PBI and between PBI techniques. METHODS: A systematic review was performed to identify modern randomized studies listed in MEDLINE from 2005 to 2020. PBI trials were divided into external beam radiation and brachytherapy techniques, with intraoperative radiation excluded. A Bayesian logistic regression model evaluated the risk of ipsilateral breast tumor recurrence (IBTR) and acute and chronic toxicities. The primary outcome was IBTR at 5 years with WBI compared with PBI. RESULTS: A total of 9758 patients from 7 studies were included (4840-WBI, 4918-PBI). At 5 years, no statistically significant difference in the rate of IBTR was noted between PBI (1.8%, 95% HPD 0.68-3.2%) and WBI (1.7%, 95% HPD 0.92-2.4%). By PBI technique, the 5-year rate of IBTR rate for external beam was 1.7% and 2.2% for brachytherapy. Rates of grade 2 + acute toxicity were 7.1% with PBI versus 47.5% with WBI. For late toxicities, grade 2/3 rates were 0%/0% with PBI compared with 1.0%/0% with WBI. CONCLUSIONS: IBTR rates were similar between PBI and WBI with no significant differences noted by PBI technique; PBI had reduced acute toxicities compared to WBI. Because studies did not provide toxicity data in a consistent fashion, definitive conclusions cannot be made with additional data from randomized trials needed to compare toxicity profiles between PBI techniques.

Long-term primary results of accelerated partial breast irradiation after breast-conserving surgery for early-stage breast cancer: a randomised, phase 3, equivalence trial.

BACKGROUND: Whole-breast irradiation after breast-conserving surgery for patients with early-stage breast cancer decreases ipsilateral breast-tumour recurrence (IBTR), yielding comparable results to mastectomy. It is unknown whether accelerated partial breast irradiation (APBI) to only the tumour-bearing quadrant, which shortens treatment duration, is equally effective. In our trial, we investigated whether APBI provides equivalent local tumour control after lumpectomy compared with whole-breast irradiation. METHODS: We did this randomised, phase 3, equivalence trial (NSABP B-39/RTOG 0413) in 154 clinical centres in the USA, Canada, Ireland, and Israel. Adult women (>18 years) with early-stage (0, I, or II; no evidence of distant metastases, but up to three axillary nodes could be positive) breast cancer (tumour size ≤3 cm; including all histologies and multifocal breast cancers), who had had lumpectomy with negative (ie, no detectable cancer cells) surgical margins, were randomly assigned (1:1) using a biased-coin-based minimisation algorithm to receive either whole-breast irradiation (whole-breast irradiation group) or APBI (APBI group). Whole-breast irradiation was delivered in 25 daily fractions of 50 Gy over 5 weeks, with or without a supplemental boost to the tumour bed, and APBI was delivered as 34 Gy of brachytherapy or 38·5 Gy of external bream radiation therapy in 10 fractions, over 5 treatment days within an 8-day period. Randomisation was stratified by disease stage, menopausal status, hormone-receptor status, and intention to receive chemotherapy. Patients, investigators, and statisticians could not be masked to treatment allocation. The primary outcome of invasive and non-invasive IBTR as a first recurrence was analysed in the intention-to-treat population, excluding those patients who were lost to follow-up, with an equivalency test on the basis of a 50% margin increase in the hazard ratio (90% CI for the observed HR between 0·667 and 1·5 for equivalence) and a Cox proportional hazard model. Survival was assessed by intention to treat, and sensitivity analyses were done in the per-protocol population. This trial is registered with ClinicalTrials.gov, NCT00103181. FINDINGS: Between March 21, 2005, and April 16, 2013, 4216 women were enrolled. 2109 were assigned to the whole-breast irradiation group and 2107 were assigned to the APBI group. 70 patients from the whole-breast irradiation group and 14 from the APBI group withdrew consent or were lost to follow-up at this stage, so 2039 and 2093 patients respectively were available for survival analysis. Further, three and four patients respectively were lost to clinical follow-up (ie, survival status was assessed by phone but no physical examination was done), leaving 2036 patients in the whole-breast irradiation group and 2089 in the APBI group evaluable for the primary outcome. At a median follow-up of 10·2 years (IQR 7·5-11·5), 90 (4%) of 2089 women eligible for the primary outcome in the APBI group and 71 (3%) of 2036 women in the whole-breast irradiation group had an IBTR (HR 1·22, 90% CI 0·94-1·58). The 10-year cumulative incidence of IBTR was 4·6% (95% CI 3·7-5·7) in the APBI group versus 3·9% (3·1-5·0) in the whole-breast irradiation group. 44 (2%) of 2039 patients in the whole-breast irradiation group and 49 (2%) of 2093 patients in the APBI group died from recurring breast cancer. There were no treatment-related deaths. Second cancers and treatment-related toxicities were similar between the two groups. 2020 patients in the whole-breast irradiation group and 2089 in APBI group had available data on adverse events. The highest toxicity grade reported was: grade 1 in 845 (40%), grade 2 in 921 (44%), and grade 3 in 201 (10%) patients in the APBI group, compared with grade 1 in 626 (31%), grade 2 in 1193 (59%), and grade 3 in 143 (7%) in the whole-breast irradiation group. INTERPRETATION: APBI did not meet the criteria for equivalence to whole-breast irradiation in controlling IBTR for breast-conserving therapy. Our trial had broad eligibility criteria, leading to a large, heterogeneous pool of patients and sufficient power to detect treatment equivalence, but was not designed to test equivalence in patient subgroups or outcomes from different APBI techniques. For patients with early-stage breast cancer, our findings support whole-breast irradiation following lumpectomy; however, with an absolute difference of less than 1% in the 10-year cumulative incidence of IBTR, APBI might be an acceptable alternative for some women. FUNDING: National Cancer Institute, US Department of Health and Human Services.

Shortened radiation therapy schedules for early-stage breast cancer: a review of hypofractionated whole-breast irradiation and accelerated partial breast irradiation.

Breast-conserving therapy consisting of segmental mastectomy followed by whole-breast irradiation (WBI) has become widely accepted as an alternative to mastectomy as a treatment for women with early-stage breast cancer. WBI is typically delivered over the course of 5-6 weeks to the whole breast. Hypofractionated whole-breast irradiation and accelerated partial breast irradiation have developed as alternative radiation techniques for select patients with favorable early-stage breast cancer. These radiation regimens allow for greater patient convenience and the potential for decreased health care costs. We review here the scientific rationale behind delivering a shorter course of radiation therapy using these distinct treatment regimens in this setting as well as an overview of the published data and pending trials comparing these alternative treatment regimens to WBI.

Partial Breast Irradiation for Patients With Early-Stage Invasive Breast Cancer or Ductal Carcinoma In Situ: An ASTRO Clinical Practice Guideline.

PURPOSE: This guideline provides evidence-based recommendations on appropriate indications and techniques for partial breast irradiation (PBI) for patients with early-stage invasive breast cancer and ductal carcinoma in situ. METHODS: ASTRO convened a task force to address 4 key questions focused on the appropriate indications and techniques for PBI as an alternative to whole breast irradiation (WBI) to result in similar rates of ipsilateral breast recurrence (IBR) and toxicity outcomes. Also addressed were aspects related to the technical delivery of PBI, including dose-fractionation regimens, target volumes, and treatment parameters for different PBI techniques. The guideline is based on a systematic review provided by the Agency for Healthcare Research and Quality. Recommendations were created using a predefined consensus-building methodology and system for grading evidence quality and recommendation strength. RESULTS: PBI delivered using 3-dimensional conformal radiation therapy, intensity modulated radiation therapy, multicatheter brachytherapy, and single-entry brachytherapy results in similar IBR as WBI with long-term follow-up. Some patient characteristics and tumor features were underrepresented in the randomized controlled trials, making it difficult to fully define IBR risks for patients with these features. Appropriate dose-fractionation regimens, target volume delineation, and treatment planning parameters for delivery of PBI are outlined. Intraoperative radiation therapy alone is associated with a higher IBR rate compared with WBI. A daily or every-other-day external beam PBI regimen is preferred over twice-daily regimens due to late toxicity concerns. CONCLUSIONS: Based on published data, the ASTRO task force has proposed recommendations to inform best clinical practices on the use of PBI.

Preliminary results of centralized HER2 testing in ductal carcinoma in situ (DCIS): NSABP B-43.

NSABP B-43 is the first prospective, randomized phase III multi-institution clinical trial targeting high-risk, HER2-positive DCIS. It compares whole breast irradiation alone with WBI given concurrently with trastuzumab in women with HER2-positive DCIS treated by lumpectomy. The primary aim is to determine if trastuzumab plus radiation will reduce in-breast tumor recurrence. HER2-positive DCIS was previously estimated at >50 %, occurring primarily in ER-negative, comedo-type DCIS of high nuclear grade. There has been no documented centralized multi-institutional HER2 analysis of DCIS. NSABP B-43 provides a unique opportunity to evaluate this in a large cohort of DCIS patients. Patients undergoing lumpectomy for DCIS without evidence of an invasive component are eligible. A central review of each patient's pure DCIS lesion is carried out by immunohistochemistry analysis. If the lesion is 2+, FISH analysis is performed. Patients whose tumors are HER2 3+ or FISH-positive are randomly assigned to receive two doses of trastuzumab during WBI or WBI alone. NSABP B-43 opened 11/9/08. As of 7/31/2013, 5,861 patients have had specimens received centrally, and 5,645 of those had analyzable blocks; 1,969 (34.9 %) were HER2 positive. A total of 1,428 patients have been accrued, 1,137 (79.6 %) of whom have follow-up information. The average follow-up time for the 1,137 patients is 23.3 months. No grade 4 or 5 toxicity has been observed. In NSABP B-43 the HER2-positive rate for pure DCIS among patients undergoing breast-preserving surgery is 34.9 %, lower than the previously reported rate. No trastuzumab-related safety signals have been observed. Interest in this trial has been robust.

Ultrashort courses of adjuvant breast radiotherapy: wave of the future or a fool's errand?

In accelerated partial breast irradiation (APBI), the most commonly used fractionation schemes include 340 or 385 centigrays delivered in a twice daily administration. A further progression of the APBI literature has been the recent interest in extremely short courses of adjuvant radiotherapy, usually delivered by intraoperative radiotherapy techniques. This newer area of single-fraction radiotherapy approaches remains highly contentious. In particular, the recently reported TARGIT trial has been the subject of both praise and scorn, and a critical examination of the trial data and the underlying hypotheses is warranted. Short-term outcomes of the related Italian ELIOT approach have also been reported. Although the assumptions of linear quadratic formalism are likely to hold true in the range of 2 to 8 grays, equating different schedules beyond this range is problematic. A major problem of current single-fraction approaches is that the treatment doses are chosen empirically, or are based on tolerability, or on the physical dose delivery characteristics of the chosen technology rather than radiobiological rationale. This review article summarizes the current data on ultrashort courses of adjuvant breast radiotherapy and highlights both the promise and the potential pitfalls of the abbreviated treatment.

ACR appropriateness criteria(®) ductal carcinoma in situ.

Ductal carcinoma in situ (DCIS) describes a wide spectrum of non-invasive tumors which carry a significant risk of invasive relapse, thus prevention of local recurrence is vital. For appropriate patients with limited disease, management with breast conserving surgery (BCS) followed by whole-breast radiation (RT) is supported by multiple Phase III studies, but mastectomy may be appropriate in selected patients. Omission of RT may also be reasonable in some patients, though which criteria are to be utilized remain unclear, and the existing data are contradictory with limited follow-up. Various RT techniques such as boost to the tumor bed, partial breast radiation or hypofractionated, whole-breast RT are increasingly utilized but the data to support their use specifically in DCIS is limited. Tamoxifen also increases local control for ER + DCIS, adding to the complexity of the local treatment management. This article reviews the existing scientific evidence, the controversies surrounding local management, and clinical guidelines for DCIS based on the group consensus by the ACR Breast Expert Panel. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances where evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

ACR Appropriateness Criteria® conservative surgery and radiation--stage I and II breast carcinoma: expert panel on radiation oncology: breast.

Breast conservation is a safe and effective alternative to mastectomy for the majority of women with early-stage breast cancer. Adjuvant radiation therapy lowers the risk of recurrence within the breast and also confers a survival benefit. Although acute side effects of radiation therapy are generally well tolerated; efforts are ongoing to minimize the long-term side effects of radiation, most prominently atherosclerotic heart disease. Efforts to minimize radiation therapy are also underway. They include omitting treatment altogether in the elderly and using accelerated, hypofractionated whole-breast irradiation, and accelerated partial-breast irradiation. Several randomized studies are ongoing to determine the efficacy, safety, and appropriate patients for these shorter treatments.

ACR appropriateness criteria® locally advanced breast cancer.

Locally advanced breast cancer (LABC) is a disease that is heterogeneous in its presentation, potentially curable, and generally necessitating multidisciplinary management. Radiation therapy (RT) plays an important role in the management of LABC. The integration of radiation with surgery, chemotherapy, and sometimes breast reconstruction can be complex. The American College of Radiology Appropriateness Criteria Breast Committee aims to provide guidance for the management of a variety of LABC cases. The American College of Radiology Appropriateness Criteria is evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances where evidence is either lacking or not definitive, expert opinion may be used to recommend imaging or treatment.

Comparison of Radiation With or Without Concurrent Trastuzumab for HER2-Positive Ductal Carcinoma In Situ Resected by Lumpectomy: A Phase III Clinical Trial.

PURPOSE: Preclinical studies report that trastuzumab (T) can boost radiotherapy (RT) effectiveness. The primary aim of the B-43 trial was to assess the efficacy of RT alone vs concurrent RT plus T in preventing recurrence of ipsilateral breast cancer (IBTR) in women with ductal carcinoma in situ (DCIS). PATIENTS AND METHODS: Eligibility: Eastern Cooperative Oncology Group (ECOG) performance status 0 or 1, DCIS resected by lumpectomy, known estrogen receptor (ER) and/or progesterone receptor (PgR), and human epidermal growth factor receptor 2 (HER2) status by centralized testing. Whole-breast RT was given concurrently with T. Stratification was by menopausal status, adjuvant endocrine therapy plan, and nuclear grade. Definitive intent-to-treat primary analysis was to be conducted when either 163 IBTR events occurred or all accrued patients were on study ≥ 5 years. RESULTS: There were 2,014 participants who were randomly assigned. Median follow-up time as of December 31, 2019, was 79.2 months. At primary definitive analysis, 114 IBTR events occurred: RT arm, 63 and RT plus T arm, 51 (hazard ratio [HR], 0.81; 95% CI, 0.56 to 1.17; P value = .26). There were 34 who were invasive: RT arm, 18 and RT plus T arm, 20 (HR, 1.11; 95% CI, 0.59 to 2.10; P value = .71). Seventy-six were DCIS: RT arm, 45 and RT plus T arm, 31 (HR, 0.68; 95% CI, 0.43 to 1.08; P value = .11). Annual IBTR event rates were: RT arm, 0.99%/y and RT plus T arm, 0.79%/y. The study did not reach the 163 protocol-specified events, so the definitive analysis was triggered by all patients having been on study for ≥ 5 years. CONCLUSION: Addition of T to RT did not achieve the objective of 36% reduction in IBTR rate but did achieve a modest but statistically nonsignificant reduction of 19%. Nonetheless, this trial had negative results. Further exploration of RT plus T is needed in HER2-positive DCIS before its routine delivery in patients with DCIS resected by lumpectomy.

Effectiveness of Breast-Conserving Surgery and 3-Dimensional Conformal Partial Breast Reirradiation for Recurrence of Breast Cancer in the Ipsilateral Breast: The NRG Oncology/RTOG 1014 Phase 2 Clinical Trial.

IMPORTANCE: Mastectomy is standard for recurrence of breast cancer after breast conservation therapy with whole breast irradiation. The emergence of partial breast irradiation led to consideration of its application for reirradiation after a second lumpectomy for treatment of recurrence of breast cancer in the ipsilateral breast. OBJECTIVES: To assess the effectiveness and adverse effects of partial breast reirradiation after a second lumpectomy and whether the treatment is an acceptable alternative to mastectomy. DESIGN, SETTING, AND PARTICIPANTS: The NRG Oncology/Radiation Therapy Oncology Group 1014 trial is a phase 2, single-arm, prospective clinical trial of 3-dimensional, conformal, external beam partial breast reirradiation after a second lumpectomy for recurrence of breast cancer in the ipsilateral breast after previous whole breast irradiation. The study opened on June 4, 2010, and closed June 18, 2013. Median follow-up was 5.5 years. This analysis used all data received at NRG Oncology through November 18, 2018. Eligible patients experienced a recurrence of breast tumor that was less than 3 cm and unifocal in the ipsilateral breast more than 1 year after breast-conserving therapy with whole breast irradiation and who had undergone excision with negative margins. INTERVENTIONS: Adjuvant partial breast reirradiation, 1.5 Gy twice daily for 30 treatments during 15 days (45 Gy), using a 3-dimensional conformal technique. MAIN OUTCOMES AND MEASURES: The main outcomes of the present study were the predefined secondary study objectives of recurrence of breast cancer in the ipsilateral breast, late adverse events (>1 year after treatment), mastectomy incidence, distant metastasis-free survival, overall survival, and circulating tumor cell incidence. RESULTS: A total of 65 women were enrolled, with 58 evaluable for analysis (mean [SD] age, 65.12 [9.95] years; 48 [83%] white). Of the recurrences of breast cancer in the ipsilateral breast, 23 (40%) were noninvasive and 35 (60%) were invasive. In all 58 patients, 53 (91%) had tumors 2 cm or smaller. All tumors were clinically node negative. A total of 44 patients (76%) tested positive for estrogen receptor, 33 (57%) for progesterone receptor, and 10 (17%) for ERBB2 (formerly HER2 or HER2/neu) overexpression. Four patients had breast cancer recurrence, with a 5-year cumulative incidence of 5% (95% CI, 1%-13%). Seven patients underwent ipsilateral mastectomies for a 5-year cumulative incidence of 10% (95% CI, 4%-20%). Both distant metastasis-free survival and overall survival rates were 95% (95% CI, 85%-98%). Four patients (7%) had grade 3 and none had grade 4 or higher late treatment adverse events. CONCLUSIONS AND RELEVANCE: For patients experiencing recurrence of breast cancer in the ipsilateral breast after lumpectomy and whole breast irradiation, a second breast conservation was achievable in 90%, with a low risk of re-recurrence of cancer in the ipsilateral breast using adjuvant partial breast reirradiation. This finding suggests that this treatment approach is an effective alternative to mastectomy.

Patterns of Failure Observed in the 2-Step Institution Credentialing Process for NRG Oncology/Radiation Therapy Oncology Group 1005 (NCT01349322) and Lessons Learned.

PURPOSE: To investigate patterns of failure in institutional credentialing submissions to NRG/RTOG 1005 with the aim of improving the quality and consistency for future breast cancer protocols. METHODS AND MATERIALS: NRG/RTOG 1005 allowed the submission of 3-dimensional conformal radiation therapy (3DCRT), intensity-modulated radiation therapy (IMRT), and simultaneous integrated boost (SIB) breast plans. Credentialing required institutions to pass a 2-step quality assurance (QA) process: (1) benchmark, requiring institutions to create a plan with no unacceptable deviations and ≤1 acceptable variation among the dose volume (DV) criteria, and (2) rapid review, requiring each institution's first protocol submission to have no unacceptable deviations among the DV criteria or contours. Overall rates, number of resubmissions, and reasons for resubmission were analyzed for each QA step. RESULTS: In total, 352 institutions participated in benchmark QA and 280 patients enrolled had rapid review QA. Benchmark initial failure rates were similar for 3DCRT (18%), IMRT (17%), and SIB (18%) plans. For 3DCRT and IMRT benchmark plans, ipsilateral lung most frequently failed the DV criteria, and SIB DV failures were seen most frequently for the heart. Rapid review contour initial failures (35%) were due to target rather than organs at risk. For 29% of the rapid review initial failures, the planning target volume boost eval volume was deemed an unacceptable deviation. CONCLUSIONS: The review of the benchmark and rapid review QA submissions indicates that acceptable variations or unacceptable deviations for the ipsilateral lung and heart dose constraints were the most commonly observed cause of benchmark QA failure, and unacceptable deviations in target contouring, rather than normal structure contouring, were the most common cause of rapid review QA failure. These findings suggest that a rigorous QA process is necessary for high quality and homogeneity in radiation therapy in multi-institutional trials of breast cancer to ensure that the benefits of radiation therapy far outweigh the risks.

Skin and chest wall dose with multi-catheter and MammoSite breast brachytherapy: Implications for late toxicity.

PURPOSE: Accelerated partial breast irradiation (APBI) continues to increase in popularity. Up to 14% of patients treated with the MammoSite (MS) report some degree of chronic pain, which may be related to chest wall toxicity. Reports from several institutions using the multicatheter (MC) technique have not shown associated elevated chest wall toxicity. Additionally, a recent investigation has suggested that increased toxicity may occur with the MS when the dose to the chest wall exceeds 125% of the prescribed dose. This investigation compares the skin and chest wall doses of a cohort of patients treated with the MC technique to a group treated with the MS. METHODS AND MATERIALS: The dosimetric data for 43 patients treated with the MC technique and 83 patients treated with the MS at Virginia Commonwealth University were reviewed. This cohort represents consecutively treated patients from our most recent experience to minimize any learning curve effect on dosimetry. Plans were generated using 3D software (Brachyvision, Varian Medical Systems, Inc., Palo Alto, CA). Multiple dwell positions were used for all MS patients to optimize dose delivery. The minimum distances from the planning target volume to the skin and chest wall were calculated, as well as the maximum doses delivered to the skin and chest wall. RESULTS: The mean skin distances for patients treated with the MC technique and the MS were 0.5 and 0.9cm, respectively (p<0.002). Despite the significantly smaller mean skin distance, the mean skin dose for the MC technique was only 2.3Gy per fraction (67% of prescription dose). The mean skin dose for the MS was 3.2Gy per fraction (94% of prescription dose, p<0.001). The mean chest wall distance was 0.9cm for the MC technique and 1.0cm for the MS (p=0.55). Again, the mean chest wall dose for the MC technique was only 2.3Gy per fraction (67% of prescription dose). The mean skin dose for the MS was 3.6Gy per fraction (105% of prescription dose, p<0.001). The percentage of patients receiving skin doses in excess of 125% for the MC and MS were 0% and 9.6%, respectively. The percentage of patients receiving chest wall doses in excess of 125% for the MC and MS were 0% and 38.6%, respectively. CONCLUSION: The MC technique results in more conformal dose delivery, with significantly lower mean skin and chest wall doses. Treatment with the MS was associated with significantly more patients receiving doses to the skin or chest wall in excess of 125% of the prescription. Given the limited followup available for the MS, and the significant dose delivered to the chest wall, the use of this device may be associated with a higher incidence of late chest wall toxicity than previously expected.

Lessons Learned From Hurricane Maria in Puerto Rico: Practical Measures to Mitigate the Impact of a Catastrophic Natural Disaster on Radiation Oncology Patients.

PURPOSE: Although the wind, rain, and flooding of Hurricane Maria in Puerto Rico abated shortly after its landfall on September 20, 2017, the disruption of the electrical, communications, transportation, and medical infrastructure of the island was unprecedented in scope and caused lasting harm for many months afterward. A compilation of recommendations from radiation oncologists who were in Puerto Rico during the disaster, and from a panel of American Society for Radiation Oncology (ASTRO) cancer experts was created. METHODS AND MATERIALS: Radiation oncologists throughout Puerto Rico collaborated and improvised to continue treating patients in the immediate aftermath of the storm and as routine clinical operations were restored gradually. Empirical lessons from the experience of radiation therapy administration in this profoundly altered context of limited resources, impaired communication, and inadequate transportation were organized into a recommended template, applicable to any radiation oncology practice. ASTRO disease-site experts provided evidence-guidelines for mitigating the impact of a 2- to 3-week interruption in radiation therapy. RESULTS: Practical measures to mitigate the medical impact of a disaster are summarized within the framework of "Prepare, Communicate, Operate, Compensate." Specific measures include the development of an emergency operations plan tailored to specific circumstances, prospective coordination with other radiation oncology clinics before a disaster, ongoing communications with emergency management organizations, and routine practice of alternate methods to disseminate information among providers and patients. CONCLUSIONS: These recommendations serve as a starting point to assist any radiation oncology practice in becoming more resiliently prepared for a local or regional disruption from any cause. Disease-site experts provide evidence-based guidelines on how to mitigate the impact of a 2- to 3-week interruption in radiation therapy for lung, head and neck, uterine cervix, breast, and prostate cancers through altered fractionation or dose escalation.

A Phase II trial of brachytherapy alone after lumpectomy for select breast cancer: tumor control and survival outcomes of RTOG 95-17.

PURPOSE: Radiation Therapy Oncology Group 95-17 is a prospective Phase II cooperative group trial of accelerated partial breast irradiation (APBI) alone using multicatheter brachytherapy after lumpectomy in select early-stage breast cancers. Tumor control and survival outcomes are reported. METHODS AND MATERIALS: Eligibility criteria included Stage I/II breast carcinoma confirmed to be <3 cm, unifocal, invasive nonlobular histology with zero to three positive axillary nodes without extracapsular extension. APBI treatment was delivered with either low-dose-rate (LDR) (45 Gy in 3.5-5 days) or high-dose-rate (HDR) brachytherapy (34 Gy in 10 twice-daily fractions over 5 days). End points evaluated included in-breast control, regional control, mastectomy-free rate, mastectomy-free survival, disease-free survival, and overall survival. The study was designed to analyze the HDR and LDR groups separately and without comparison. RESULTS: Between 1997 and 2000, 100 patients were accrued and 99 were eligible; 66 treated with HDR brachytherapy and 33 treated with LDR brachytherapy. Eighty-seven patients had T1 lesions and 12 had T2 lesions. Seventy-nine were pathologically N0 and 20 were N1. Median follow-up in the HDR group is 6.14 years with the 5-year estimates of in-breast, regional, and contralateral failure rates of 3%, 5%, and 2%, respectively. The LDR group experienced similar results with a median follow-up of 6.22 years. The 5-year estimates of in-breast, regional, and contralateral failure rates of 6%, 0%, and 6%, respectively. CONCLUSION: Patients treated with multicatheter partial breast brachytherapy in this trial experienced excellent in-breast control rates and overall outcome that compare with reports from APBI studies with similar extended follow-up.

Evaluation of coplanar partial left breast irradiation using tomotherapy-based topotherapy.

PURPOSE: To investigate the use of topotherapy for accelerated partial breast irradiation through field-design optimization and dosimetric comparison to linear accelerator-based three-dimensional conformal radiotherapy (3D-CRT) and intensity-modulated radiation therapy (IMRT). METHODS AND MATERIALS: Hypothetical 3-cm lumpectomy sites were contoured in each quadrant of a left breast by using dosimetric guidelines from the National Surgical Adjuvant Breast and Bowel Project B-39/Radiation Therapy Oncology Group 0413 protocol. Coplanar intensity-modulated topotherapy treatment plans were optimized by using two-, three-, four-, five-, and seven-field arrangements for delivery by the tomotherapy unit with fixed gantry angles. Optimized noncoplanar five-field 3D-CRT and IMRT were compared with corresponding topotherapy plans. RESULTS: On average, 99.5% +/- 0.5% of the target received 100% of the prescribed dose for all topotherapy plans. Average equivalent uniform doses ranged from 1.20-2.06, 0.79-1.76, and 0.10-0.29 Gy for heart, ipsilateral lung, and contralateral lung, respectively. Average volume of normal breast exceeding 90% of the prescription and average area of skin exceeding 35 Gy were lowest for five-field plans. Average uniformity indexes for five-field plans using 3D-CRT, IMRT, and topotherapy were 1.047, 1.050, and 1.040, respectively. Dose-volume histograms and calculated equivalent uniform doses of all three techniques illustrate clinically equivalent doses to ipsilateral breast, lung, and heart. CONCLUSIONS: This dosimetric evaluation for a single patient shows that coplanar partial breast topotherapy provides good target coverage with exceptionally low dose to organs at risk. Use of more than five fields provided no additional dosimetric advantage. A comparison of five-field topotherapy to 3D-CRT and IMRT for accelerated partial breast irradiation illustrates equivalent target conformality and uniformity.

Multi-institutional experience using the MammoSite radiation therapy system in the treatment of early-stage breast cancer: 2-year results.

PURPOSE: To present a retrospective multi-institutional experience of patients treated with the MammoSite radiation therapy system (RTS). METHODS AND MATERIALS: Nine institutions participated in a pooled analysis of data evaluating the clinical experience of the MammoSite RTS for delivering accelerated partial breast irradiation. Between 2000 and 2004, 483 patients were treated with the MammoSite RTS to 34 Gy delivered in 10 fractions. Treatment parameters were analyzed to identify factors affecting outcome. RESULTS: Median follow-up was 24 months (minimum of 1 year). Overall, infection was documented in 9% of patients, but the rate was only 4.8% if the catheter was placed after lumpectomy. Six patients (1.2%) experienced an in-breast failure; four failures occurred remote from the lumpectomy site (elsewhere failure). Cosmetic results were good/excellent in 91% of patients. Treatment parameters identified as significant on univariate analysis were tested in multivariate regression analysis. The closed-cavity placement technique significantly reduced the risk of infection (p = 0.0267). A skin spacing of <6 mm increased the risk of severe acute skin reaction (p = 0.0178) and telangiectasia (p = 0.0280). The use of prophylactic antibiotics reduced the risk of severe acute skin reaction (p < 0.0001). The use of multiple dwell positions reduced the risk of severe hyperpigmentation (p = 0.0278). Infection was associated with an increased risk of fair or poor overall cosmesis (p = 0.0009). CONCLUSIONS: In this series of patients, the MammoSite RTS seems to have acceptable toxicity rates and cosmetic outcomes, comparable to those with whole-breast radiotherapy. On the basis of these data, the closed-cavity placement technique, use of prophylactic antibiotics, use of multiple dwell positions, and a minimum skin spacing of 6 mm seem to improve patient outcome.