Meta-Analysis of 5-Fraction Preoperative Radiotherapy for Soft Tissue Sarcoma.

OBJECTIVES: Studies investigating preoperative 5-fraction radiation therapy (RT) for soft tissue sarcoma (STS) are limited. We performed a meta-analysis to determine the efficacy and safety of this treatment paradigm. METHODS: This study-level meta-analysis was conducted using Bayesian methods. Statistical estimation for risk of outcome rates was conducted by posterior mean and 95% highest posterior density (HPD) intervals. Studies with 2-year local control (LC) and description of major wound complications (MWC) per the CAN-NCIC-SR2 study were included and served as the primary endpoints. Secondary endpoints included rates of acute and late toxicity. A total of 10 studies were identified and 7 met the inclusion criteria. Subgroup analyses were performed for ≥30 Gy vs <30 Gy. RESULTS: A total of 209 patients from 7 studies were included. Five studies used ≥30 Gy (n=144), and 2 studies <30 Gy (n=64). Median follow-up was 29 months (range: 21 to 57 mo). Primary tumor location was lower extremity in 68% and upper extremity in 22%. Most tumors were intermediate or high grade (95%, 160/169), and 50% (79/158) were >10 cm. The two-year LC for the entire cohort was 96.9%, and the rate of MWC was 30.6%. There was a trend toward improved LC with ≥ 30 Gy (95% HPD: 0.95 to 0.99 vs 0.84 to 0.99). There was no difference in MWC (95% HPD: 0.18 to 0.42 vs 0.17 to 0.55) or late toxicity between the groups. CONCLUSION: Preoperative 5-fraction RT for STS demonstrates excellent 2-year LC with MWC and toxicity similar to standard fractionation preoperative RT. Multi-institutional trials with a universal RT protocol are warranted.

Cancer Diagnoses and Use of Radiation Therapy Among Persons Experiencing Homelessness.

PURPOSE: Persons experiencing homelessness (PEH) have low rates of cancer screening and worse cancer mortality compared with persons not experiencing homelessness. Data regarding cancer diagnosis and treatment in PEH are limited. We investigated cancer prevalence and use of radiation therapy (RT) in PEH. METHODS AND MATERIALS: Patients presenting between January 1, 2014, and September 27, 2021, at a large metropolitan hospital system were assessed for homelessness via intake screening or chart search. PEH data were cross-referenced with the institution's cancer database to identify PEH with cancer diagnoses. Demographic, clinical, and treatment variables were abstracted. RESULTS: Of a total of 9654 (9250 evaluable) PEH with a median age of 42 years, 81 patients (0.88%) had at least 1 cancer diagnosis and 5 had multiple diagnoses, for a total of 87 PEH with at least 1 cancer diagnosis. The median age at diagnosis was 60 years. In total, 43% were female and 51% were Black, and 43% presented with advanced or metastatic disease. Lung (17%), prostate (15%), leukemia/lymphoma (13%), and head/neck (9%) were the most common diagnoses. In total, 17% of patients underwent surgery alone, 13% received chemotherapy alone, 14% received RT alone, and 6% received hormone therapy alone. A total of 8% of patients underwent no treatment, and 43% underwent multimodality therapy. In total, 58% of treated patients never achieved disease-free status. Of the 31 patients who received RT, 87% received external beam RT. Most patients (70%) received hypofractionated regimens. For patients who had multifraction treatment, the treatment completion rate was 85%, significantly lower than the departmental completion rate of 98% (P < .00001). CONCLUSIONS: In a large cohort of PEH in a metropolitan setting, cancer diagnoses were uncommon and were frequently in advanced stages. Most patients underwent single-modality treatment or no treatment at all. Despite the use of hypofractionation, the RT completion rate was low, likely reflecting complex barriers to care. Further interventions to optimize cancer diagnosis and treatment in PEH are urgently needed.

Early outcomes of ultra-hypofractionated preoperative radiation therapy for soft tissue sarcoma followed by immediate surgical resection.

BACKGROUND: There is increasing interest in shorter courses of radiation therapy (RT) in the management of soft tissue sarcoma (STS). We report our institutional experience for patients undergoing ultra-hypofractionated preoperative RT followed by immediate resection. METHODS: An IRB approved review of patients treated with preoperative 5 fraction, once daily RT followed by immediate resection (within 7 days) for STS of the extremity or trunk was conducted. The primary endpoints are major wound complications and local control (LC). Secondary endpoints include grade ≥ 2 toxicity, metastasis free survival (MFS), and overall survival (OS). RESULTS: Twenty-two patients with a median age of 67 years (range 30-87) and median follow-up of 24.5 months (IQR 17.0-35.7) met eligibility criteria; 18/22 patients (81.8 %) had ≥ 1 year follow-up. Primary tumor location was lower extremity in 15 patients (68.2 %), upper extremity in 5 (22.7 %), and trunk in 2 (9.1 %). All patients received 30 Gy in 5 fractions. The median time to resection following RT was 1 day (range 0-5). The median time from biopsy to resection was 34 days (range 20-69). Local control was 100 %; in patients with localized disease, 2-year MFS and OS were 71.3 % and 76.9 %, respectively. Major wound complications occurred in 9 patients (40.9 %), with wound complications requiring reoperation occurring in 8 patients (36.4 %). Other acute and late grade ≥ 2 toxicities were seen in 0 and 4 patients (18.2 %), respectively. CONCLUSION: Ultra-hypofractionated preoperative RT followed by immediate resection permits expedited completion of oncologic therapy with early results demonstrating excellent local control and acceptable toxicity. Prospective data with long-term follow-up is needed.

Five Fraction External Beam Partial Breast Irradiation: A User's Guide.

OBJECTIVE: Mature follow up from multiple randomized trials have demonstrated the safety and efficacy of external beam partial breast irradiation (PBI) for appropriately selected patients with early stage breast cancer. Despite this evidence, external beam PBI remains underutilized. In this user guide we outline patient selection, workflow, and address possible challenges to aid in implementation of evidence-based external beam PBI. MATERIALS AND METHODS: Review of the current guidelines for PBI suitability, surgical considerations, treatment technique, simulation, contouring, and treatment planning, citing the latest published literature to support PBI utilization. RESULTS: Prospective data supports the use of 30 Gy in 5 fractions delivered with intensity modulated radiation therapy on a daily or every other day basis for a significant proportion of early stage breast cancer patients. The surgical cavity must be clearly visualized on treatment planning scan, recommend 3-5 weeks post-operatively, and the recommended clinical target volume expansion on the surgical cavity is 0.5-1.0 cm. A planning target volume expansion, based on motion management and image guidance, of 0.5-1.0 cm should be used. Organ at risk dose constraints of heart V3Gy ≤10% and contralateral breast Dmax ≤1 Gy are often achievable. CONCLUSIONS: Five fraction external beam PBI is a highly effective treatment with very limited toxicity for patients with early stage breast cancer following breast conserving surgery. Commonly utilized intensity modulated treatment planning techniques with plan delivery on standard linear accelerators results significant normal tissue sparing and makes implementation feasible at most radiation oncology centers.

Risk factors for breast cancer-related lymphedema in patients undergoing 3 years of prospective surveillance with intervention.

BACKGROUND: To evaluate risk factors (treatment-related, comorbidities, and lifestyle) for breast cancer-related lymphedema (BCRL) within the context of a Prospective Surveillance and Early Intervention (PSEI) model of care for subclinical BCRL. METHODS: The parent randomized clinical trial assigned patients newly diagnosed with breast cancer to PSEI with either bioimpedance spectroscopy (BIS) or tape measurement (TM). Surgical, systemic and radiation treatments, comorbidities, and lifestyle factors were recorded. Detection of subclinical BCRL (change from baseline of either BIS L-Dex ≥6.5 or tape volume ≥ 5% and < 10%) triggered an intervention with compression therapy. Volume change from baseline ≥10% indicated progression to chronic lymphedema and need for complex decongestive physiotherapy. In this secondary analysis, multinomial logistic regressions including main and interaction effects of the study group and risk factors were used to test for factor associations with outcomes (no lymphedema, subclinical lymphedema, progression to chronic lymphedema after intervention, progression to chronic lymphedema without intervention). Post hoc tests of significant interaction effects were conducted using Bonferroni-corrected alphas of .008; otherwise, an alpha of .05 was used for statistical significance. RESULTS: The sample (n = 918; TM = 457; BIS = 461) was female with a median age of 58.4 years. Factors associated with BCRL risk included axillary lymph node dissection (ALND) (p < .001), taxane-based chemotherapy (p < .001), regional nodal irradiation (RNI) (p ≤ .001), body mass index >30 (p = .002), and rurality (p = .037). Mastectomy, age, hypertension, diabetes, seroma, smoking, and air travel were not associated with BCRL risk. CONCLUSIONS: Within the context of 3 years of PSEI for subclinical lymphedema, variables of ALND, taxane-based chemotherapy, RNI, body mass index >30, and rurality increased risk.

A multi-institutional prediction model to estimate the risk of recurrence and mortality after mastectomy for T1-2N1 breast cancer.

BACKGROUND: Post-mastectomy radiation therapy (PMRT) in women with pathologic stage T1-2N1M0 breast cancer is controversial. METHODS: Data from five North American institutions including women undergoing mastectomy without neoadjuvant therapy with pT1-2N1M0 breast cancer treated from 2006 to 2015 were pooled for analysis. Competing-risks regression was performed to identify factors associated with locoregional recurrence (LRR), distant metastasis (DM), overall recurrence (OR), and breast cancer mortality (BCM). RESULTS: A total of 3532 patients were included for analysis with a median follow-up time among survivors of 6.8 years (interquartile range [IQR], 4.5-9.5 years). The 2154 (61%) patients who received PMRT had significantly more adverse risk factors than those patients not receiving PMRT: younger age, larger tumors, more positive lymph nodes, lymphovascular invasion, extracapsular extension, and positive margins (p < .05 for all). On competing risk regression analysis, receipt of PMRT was significantly associated with a decreased risk of LRR (hazard ratio [HR], 0.21; 95% confidence interval [CI], 0.14-0.31; p < .001) and OR (HR, 0.76; 95% CI, 0.62-0.94; p = .011). Model performance metrics for each end point showed good discrimination and calibration. An online prediction model to estimate predicted risks for each outcome based on individual patient and tumor characteristics was created from the model. CONCLUSIONS: In a large multi-institutional cohort of patients, PMRT for T1-2N1 breast cancer was associated with a significant reduction in locoregional and overall recurrence after accounting for known prognostic factors. An online calculator was developed to aid in personalized decision-making regarding PMRT in this population.

Six-Year Results From a Phase I/II Trial for Hypofractionated Accelerated Partial Breast Irradiation Using a 2-Day Dose Schedule.

BACKGROUND: To report 6-year outcomes from a phase I/II trial using balloon-based brachytherapy to deliver APBI in 2 days. METHODS: A total of 45 patients with early-stage breast cancer received adjuvant APBI in 2 days with high-dose rate (HDR) brachytherapy totaling 2800 cGy in 4 fractions (700 cGy BID) using a balloon-based applicator as part of a prospective phase I/II clinical trial. All patients had negative margins and skin spacing ≥8 mm. We evaluated toxicities (CTCAE v3) as well as ipsilateral breast tumor recurrence (IBTR), regional nodal failure (RNF), distant metastasis, disease-free survival, cause-specific survival, and overall survival. RESULTS: Median age and tumor size were 66 years old (48 to 83) and 0.8 cm (0.2 to 2.3 cm), respectively. Four percent of patients were N1 (n=2) and 73% were estrogen receptor (ER) positive (n=32). Median follow-up was 6.2 years (2.4 to 8.0 y). Nearly all toxicities at 6 years were grade 1 to 2 except 1 instance of grade 3 telangiectasia (2%). Eleven percent (n=5) of patients had chronic asymptomatic fat necrosis whereas asymptomatic seromas were noted on mammogram in 13% of cases (n=6). Cosmesis at last follow-up was good or excellent in 91% of cases (n=40) and fair in 9% (n=4). Two of the previously reported rib fractures healed with conservative measures. There were no IBTR or RNF (6 y IBTR/RNF rate 0%); however, 2 patients experienced distant metastasis (4% at 6 y). The 6-year actuarial disease-free survival, cause-specific survival, and overall survival were 96%, 100%, and 93%, respectively. CONCLUSIONS: Hypofractionated 2-day APBI using brachytherapy resulted in excellent clinical outcomes with acceptable chronic toxicities.

Four-year results using balloon-based brachytherapy to deliver accelerated partial breast irradiation with a 2-day dose fractionation schedule.

PURPOSE: We present 4-year results from a Phase I/II trial using balloon-based brachytherapy to deliver accelerated partial breast irradiation in 2 days. MATERIALS/METHODS: Forty-five patients received breast-conserving surgery followed by adjuvant radiation therapy using a balloon-based brachytherapy applicator delivering 2800 cGy in four fractions over 2 days. Outcomes analyzed include toxicities scored using the NCI Common Toxicity Criteria v3.0 scale, ipsilateral breast tumor recurrence, regional nodal failure, distant metastasis, disease-free survival, cause-specific survival, and overall survival. RESULTS: Median age was 66 years (range, 48-83 years) and median tumor size was 0.6 cm (range, 0.2-2.3 cm). Five percent of patients were node positive (n=2), whereas 73% was estrogen receptor positive (n=33). Median followup was 3.7 years (2.4-7.0 years) with greater than 2 years of followup for all patients. Only Grades 1 and 2 chronic toxicities were noted with fat necrosis (18%) and asymptomatic seromas (42%) being the most common toxicities. Seven percent of patients developed ipsilateral rib fractures (n=3), although this was not statistically associated with maximum rib dose (p=0.31). Ninety-eight percent of patients had a good or excellent radiation-related cosmetic outcome at the time of last followup. There were no ipsilateral breast tumor recurrences or regional nodal failures; however, 2 patients developed distant metastases. Four-year actuarial disease-free survival, cause-specific survival, and overall survival were 96%, 100%, and 93%, respectively. CONCLUSIONS: Treatment of early-stage breast cancer patients with breast-conserving therapy using a 2-day radiation dose schedule resulted in acceptable chronic toxicity and similar clinical outcomes as standard 5-day fractionation.