Vicini, Frank A.

PURPOSE For patients with breast cancer undergoing breast conservation, escalating the dose (boost) of radiation to the lumpectomy cavity after whole-breast irradiation (WBI) reduces ipsilateral breast recurrence (IBR) but extends treatment duration. This phase III trial investigated whether boost delivery during WBI versus after WBI provides noninferior IBR and preserves cosmetic appearance. METHODS NRG/RTOG 1005 randomly assigned patients at higher risk for IBR after lumpectomy and axillary surgery to either a sequential boost of 12 Gy in six fractions(F) or 14 Gy in 7F after WBI of 50 Gy in 25F or 42.7 Gy in 16F (sequential arm) or a concurrent boost of 8 Gy in 15F of 0.53 Gy per day with WBI of 40 Gy in 15F (concurrent arm) using 3-dimensional conformal radiation therapy (RT) or intensity-modulated RT. Based on 1.59% 5-year IBR for the sequential arm, defining the noninferiority margin as a hazard ratio upper limit on the 90% CI of 2.12, 2,312 patients provide 80% power for noninferiority of IBR as first recurrence for the concurrent arm. Secondary end points included disease-free survival and overall survival, adverse events (AEs), and cosmetic outcomes. RESULTS Between May 24, 2011, and June 20, 2014, 2,354 patients were randomly assigned, with 2,255 eligible for analysis (sequential arm, n = 1,118; concurrent arm, n = 1,137). With median follow-up of 7.3 years, there were 56 IBR events; 5- and 7-year IBR were 2.1% and 2.2% on the sequential arm and 1.9% and 2.6% on the concurrent arm, respectively. The noninferiority criterion was met: HR (90% CI): 1.31 (0.84 to 2.04), P = .037. No differences were observed in AEs, cosmetic outcomes, or survival between arms. CONCLUSION Concurrent boost during WBI results in noninferior IBR compared with sequential boost without worsening toxicity or cosmetic outcomes and reduces overall treatment time.

Abstract Background NRG Oncology NSABP B-39/RTOG 0413 compared whole-breast irradiation (WBI) to accelerated partial-breast irradiation (APBI). APBI was not equivalent to WBI in local tumor control. Secondary outcome was quality of life (QOL). Methods The QOL sub-study used validated self-report questionnaires, including the Breast Cancer Treatment Outcome Scale (BCTOS) and the 36-Item Short Form Health Survey (SF-36) vitality scale. Assessments occurred before random assignment, at treatment completion (chemotherapy or radiotherapy), 4 weeks later, at 6, 12, 24, and 36 months. Primary aims: cosmesis change equivalency (baseline to 3 years; a priori margin of equivalence 0.4 standard deviations) and fatigue change superiority (baseline to end of treatment [EOT]) for APBI vs WBI, by patient groups treated with or without chemotherapy when appropriate. Results From March 21, 2005 to May 25, 2009, 975 patients enrolled in this sub-study; 950 had follow-up data. APBI had 3-year cosmesis equivalent to WBI (95% CI = -0.0001 to -0.16; equivalence margin -0.22 to -0.22) in all patients. The APBI group without chemotherapy had less EOT fatigue (P = .011; mean score APBI 63 vs WBI 59); the APBI group receiving chemotherapy had worse EOT fatigue (P = .011; APBI 43 vs WBI 49). The APBI group reported less pain (BCTOS) at EOT (WBI 2.29 vs APBI 1.97) but worse pain at 3 years (WBI 1.62 vs APBI 1.71). APBI patients reported greater convenience of care than with WBI and reported less symptom severity at EOT and 4 weeks later. Conclusion Cosmetic outcomes were similar for the APBI and WBI groups, with small statistically significant differences in other outcomes that varied over time. Differences in fatigue and other symptoms appeared to resolve by ≥6 months. APBI may be preferred by some patients, for whom extended treatment is burdensome. ClinicalTrials.gov NCT00103181.

Abstract Background: The benefit of adjuvant regional nodal irradiation including the chest wall after mastectomy (CWI+RNI) and with whole breast irradiation (WBI+RNI) after breast conserving surgery (BCS) is well established in pts with pathologically positive axillary nodes (pN+). Pts who present with axillary node involvement (cN+), receive neoadjuvant chemotherapy (NC), and are found to be pathologically node-negative at surgery (ypN0), have lower loco-regional recurrence (LRR) rates compared to those who remain pathologically node-positive (ypN+). This phase III, randomized trial aimed to evaluate whether CWI+RNI after mastectomy or addition of RNI to WBI after BCS significantly improves invasive breast cancer recurrence-free interval (IBC-RFI) in cN+ pts found to be ypN0 after NC. Methods: Eligible pts had clinical cT1-3, N1, M0 invasive breast cancer (biopsy-proven N+ by FNA/core needle bx), completed ≥8 wks of NC (and anti-HER2 therapy if HER2+), and were ypN0 after mastectomy or BCS and sentinel node biopsy (SLNB, ≥2 nodes), axillary lymph node dissection (ALND), or both. Pts were randomized to “No RNI” (i.e., observation after mastectomy or WBI after BCS) vs. “RNI” (i.e., CWI+RNI after mastectomy or WBI+RNI after BCS). Primary endpoint was IBC-RFI. Secondary endpoints reported here: LRR-free interval (LRRFI), distant recurrence-free interval (DRFI), disease-free survival (DFS), and overall survival (OS). Study was designed to have 80% power to detect 35% reduction in annual rate of IBC-RFI for an absolute risk reduction of 4.6% (5-yr cumulative rate). Per protocol, final analysis was to occur after 172 events or 10 yrs after study initiation.Here we report the time-driven analysis prespecified in the protocol. Results: From 9/13-12/20, 1,641 pts were enrolled; 1,556 pts were available for primary event analysis; median f/u time 59.5 mos (IQR 40.7-74.1). Pt/tumor characteristics were well balanced between groups. Median age 52 yrs (range 21-84); 31% non-white; 21% cT1, 60% cT2, 19% cT3; 23% triple-negative, 21% HR+/HER2-, 56% HER2+; 58% BCS; 55% SLNB, 45% ALND+/-SLNB; and 78% had breast pathologic complete response. At the time of the analysis, 109 IBC-RFI events (63% of the planned 172) were confirmed (“No RNI”: 59, “RNI”: 50). There was no statistically significant difference between groups for IBC-RFI (HR=0.88, 95%CI 0.60-1.29; p=0.51), 5-yr point estimates: 91.8% for “No RNI” and 92.7% for “RNI.” There were no statistically significant differences between the treatment groups for secondary endpoints. There were no study-related deaths and no unexpected toxicities.Grade 4 toxicity was rare (0.1% with “No RNI”, 0.5% with “RNI”); 6.5% of pts developed grade 3 toxicity in “No RNI” and 10% in “RNI” group. Most common grade 3 toxicity was radiation dermatitis (3.3% in “No RNI,” 5.7% in “RNI”). Conclusion: In pts who present with biopsy-proven axillary node involvement and convert their axillary nodes to ypN0 after NC, CWI+RNI after mastectomy, or WBI+RNI after BCS, did not significantly improve IBC-RFI, LRRFI, DRFI, DFS, or OS. These findings suggest that downstaging involved axillary nodes with NC can result in optimization of adjuvant radiotherapy without adversely affecting oncologic outcomes. Follow-up of pts for long-term outcomes continues. NCT01872975 *EPM and JW are co-first authors. Table 1 Citation Format: Eleftherios Mamounas, Hanna Bandos, Julia White, Thomas Julian, Atif Khan, Simona Shaitelman, Mylin Torres, Frank Vicini, Patricia Ganz, Susan McCloskey, Nilendu Gupta, X. Allen Li, Peter Lucas, Nadeem Abu-Rustum, Saumil Gandhi, Rahul Tendulkar, Robert Coleman, Keiichi Fujiwara, Samantha Seaward, William Irvin, Kristin Higgins, Robert Mutter, Jean-Francois Boileau, Andrew Muskovitz, Reshma Jagsi, Anna Weiss, Curran Walter Jr., Norman Wolmark. Loco-Regional Irradiation in Patients with Biopsy-proven Axillary Node Involvement at Presentation Who Become Pathologically Node-negative After Neoadjuvant Chemotherapy: Primary Outcomes of NRG Oncology/NSABP B-51/RTOG 1304 [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr GS02-07.

508 Background: PBI is an alternative to WBI, with potentially greater therapy (tx) compliance, and better integration with chemotherapy (CTX). NSABP B-39/RTOG 0413 clinical outcome results from 2018 did not show equivalence of PBI to WBI in local tumor control; PBI was statistically inferior, but with clinically small differences. PBI may be an acceptable alternative to WBI for some women. Understanding cosmesis and quality of life (QOL) treatment outcomes is important. Methods: B-39/0413 included a prospective QOL substudy with PRO evaluation of breast cancer treatment outcomes (cosmesis, function, pain) and fatigue using BCTOS and SF-36 vitality scales. Secondary QOL parameters included treatment related symptoms, perceived convenience of care, and the BPI pain scale. The study sample was stratified by CTX or not, as CTX is given before WBI but after PBI. PRO assessments occurred before randomization, the last day of adjuvant tx [CTX or radiation], 4 wks later, and 6, 12, 24, and 36 mo later. Primary aims included comparisons of change in fatigue from baseline to end of tx and equivalency of change in cosmesis from baseline to 36 mo for PBI v WBI. Separate analyses were done for CTX and non-CTX pts, controlling for axillary dissection. Each comparison used α=0.0125. Planned sample size was 964. Results: From 3-23-05 to 5-27-09, 975 pts were enrolled in the PRO study; 950 had follow-up data. 504 did not receive CTX and 446 received CTX. In non-CTX pts, PBI had less fatigue (p=0.011) and did not meet criteria for cosmesis equivalence (97.5% CI, -0.02 to 0.22; ∆=0.20). In CTX pts, PBI had worse fatigue (p=0.011) and equivalent cosmesis to WBI (97.5% CI, -0.09 to 0.21; ∆=0.24). In both groups, PBI pts reported less pain at end of tx. In non-CTX pts, PBI had more pain at 36 mo but in CTX pts, there was no difference. Convenience of care and treatment related symptom outcomes will be presented. Conclusions: In non-CTX pts, PBI is more convenient with less fatigue and slightly poorer cosmesis at 36 mo. Cosmesis was equivalent at 36 mo in CTX pts. Support: U10CA180868, -180822, UG1CA189867. Clinical trial information: NCT00103181.