Golshan, Mehra

AbstractBackgroundThe management of early breast cancer (BC) has witnessed an uprise in the use of neoadjuvant therapy and a remarkable reshaping of the systemic therapy postneoadjuvant treatment in the last few years, with the evolution of many controversial clinical situations that require consensus.MethodsDuring the 14th Breast‐Gynecological and Immuno‐Oncology International Cancer Conference held in Egypt in 2022, a panel of 44 BC experts from 13 countries voted on statements concerning debatable challenges in the neo/adjuvant treatment setting. The recommendations were subsequently updated based on the most recent data emerging. A modified Delphi approach was used to develop this consensus. A consensus was achieved when ≥75% of voters selected an answer.Results and ConclusionsThe consensus recommendations addressed different escalation and de‐escalation strategies in the setting of neoadjuvant therapy for early BC. The recommendations recapitulate the available clinical evidence and expert opinion to individualize patient management and optimize therapy outcomes. Consensus was reached in 63% of the statements (52/83), and the rationale behind each statement was clarified.

LBA2 Background: About 6% of newly diagnosed breast cancer patients present with Stage IV disease and an intact primary tumor (IPT). Locoregional treatment (LRT) for the IPT is hypothesized to improve survival based on retrospective analyses, but randomized trials have provided conflicting data. We now report the results of E2108, a Phase 3 trial that examined the worth of LRT for the IPT following initial systemic therapy. Methods: Stage IV patients with IPT were registered, treated with optimal systemic therapy (OST) based on patient and tumor characteristics; those who did not progress during 4-8 months of OST were randomized to LRT for the IPT, or no LRT. The primary endpoint was overall survival (OS), with locoregional disease control as a secondary endpoint. Stratified log rank test and Cox proportional hazard model were used to compare OS between treatment groups. Cumulative incidence of locoregional recurrence/progression was estimated and Gray test was used for treatment group comparisons. The trial was designed to detect an improvement in 3 year OS rate from 30% with OST alone to 49.3% for OST+LRT (power 95%, 1-sided alpha 0.05) with full information expected after 152 deaths; the data monitoring committee recommended data release after 80% of full information. Results: 390 patients were enrolled between 2/8/11 and 7/23/15, and received OST. Of these, 256 eligible patients were randomized to either continued OST alone (N = 131) or OST+LRT (N = 125).There were 121 deaths and 43 locoregional progression events after a median follow up 59 months (range: 0-91). There was no significant difference in OS (3-year OS rate 68.4% in OST+LRT vs. 67.9% OST alone arm, stratified log-rank p = 0.63, HR = 1.09, 90% CI: 0.80, 1.49) or in progression-free survival (p = 0.40). The locoregional recurrence/progression was significantly higher in the OST alone arm (3-year rate 25.6% vs 10.2%, Gray test p = 0.003). Health-related quality of life (HRQOL) measured by FACT-B Trial Outcome Index was significantly worse in the OST+LRT arm than OST alone arm at 18 months post randomization (60% completion, Wilcoxon rank sum test p = 0.01), but no difference was observed at time points 6 months (74% completion) or 30 months (56% completion). Conclusions: Early local therapy does not improve survival in patients with de novo metastatic breast cancer and an IPT. Although there was a 2.5-fold higher risk of local disease progression without LRT, LRT of the IPT did not lead to improved HRQOL. Clinical trial information: NCT01242800 .

591 Background: Both Cb and Bev demonstrate activity when combined with standard chemotherapy in TNBC. CALGB 40603 is a 2x2 randomized trial that previously demonstrated that adding Cb to NACT significantly increased pathologic complete responses in the breast/axilla (pCR), while adding Bev did not (Sikov, JCO 2015). Here we report 5-year LTOs and assess factors that influenced them. Methods: 443 patients with clinical stage II-III previously untreated TNBC received 12 weeks of paclitaxel (wP) +/- Cb then dose-dense AC, +/- Bev before surgery. The primary endpoint was pCR. Analyses of LTOs (event-free survival (EFS), distant recurrence-free interval (DRFI) and overall survival (OS)), impact of residual cancer burden and other variables were secondary. Results: Median follow-up was 5.7 years (y); 5y EFS was 70.9% (95% CI; 66.7%-75.4%), DRFI 76.3% (72.3%-80.5%) and OS 76.9% (72.9%-81.2%). Pretreatment clinical stage and achieving pCR correlated with LTOs, while age, race, subtype (basal-like vs. not) and tumor grade did not. Among pCR 5y EFS was 86.4% vs. 57.5% for non-pCR (HR 0.28, 0.19-0.43), OS was 88.7% vs 66.5% (HR = 0.28, 0.17-0.44). This relationship was similar in all trial arms. Any residual disease conferred poorer outcome; compared with pCR/Residual Cancer Burden (RCB) 0, EFS HRs were 2.29 (1.32-3.97), 3.01 (1.90-4.74), and 9.67 (5.66-16.51) for RCBI, II and III, respectively. There were no improvements in LTOs with Cb (EFS HR 0.99, 0.70-1.40) or Bev (EFS HR 0.91, 0.64-1.29). In an exploratory analysis, receipt of ≥11 doses of wP was associated with better EFS (HR 1.92, 1.33-2.77); this was particularly notable in Cb-treated arms. Conclusions: As expected, regardless of treatment arm pCR was associated with markedly better LTOs, and pts with any residual disease had significantly worse outcomes. The addition of Cb or Bev to standard NACT for TNBC did not improve LTOs in this trial, although it should be noted that the trial was not powered for this endpoint. Omission of chemotherapy doses may result in poorer outcomes, especially among Cb-treated pts, which may warrant further evaluation. Support: U10CA180821; U10CA180882; Genentech; https://acknowledgments.alliancefound.org ; NCT00861705 Clinical trial information: NCT00861705.

Abstract Background:Neoadjuvant chemotherapy (NCT) is used frequently to downstage locally advanced tumors and facilitate breast conservation. However, we have previously reported that achievement of radiographic complete response (rCR) or pathologic complete response (pCR) does not impact choice of surgery for many patients. This secondary analysis reports treatment outcomes across 9 NCI comprehensive cancer centers in women receiving both NCT and breast MR imaging to assess whether treatment outcomes among women receiving NCT differs according to choice of locoregional treatment. Methods:1077 women from 9 institutions were retrospectively identified as having undergone NCT with MR imaging obtained both before and after systemic treatment. Systemic treatment regimen was not prespecified, but receipt of at least 80% of all planned cycles was required prior to final MR imaging. We performed a univariate analysis as well as a multivariable Cox proportional hazard regression to identify covariates associated with overall survival (OS), disease-free survival (DFS) and time to recurrence (TTR). rCR was defined as no residual enhancement on post-treatment breast MRI. Results:1077 patients diagnosed and treated with NCT for stage I-III invasive breast cancer from January 1, 2002 to June 16, 2014 were analyzed for all endpoints. Median follow-up was 4.2 years, (range 0.1 to 13 years). Median age of the cohort was 50 years, (range 19-87 years). 473 (43.9%) had ER(+) and/or PR(+)/HER2(-) disease, 348 (32.3%) had HER2(+) disease, and 256 (23.8%) had ER(-)/PR(-)/HER2(-) (triple negative) disease. Mastectomy or breast conserving therapy (BCT) was recorded as the definitive surgery in 675 (62.7%) and 402 (37.3%) of patients, respectively. Radiation receipt was confirmed in 84.1% of BCT and 68.3% of mastectomy patients. Overall there were 134 recurrences, 168 disease events and 89 deaths. Among patients with pCR, there were 7/161 (7.2%) recurrences in those undergoing mastectomy and 6/143 (5.1%) in those undergoing lumpectomy (p=0.81). Among patients who achieved an rCR, there were recurrences in 5% of those undergoing mastectomy and 2.9% in those undergoing lumpectomy (p=0.53). In multivariable analysis of the entire cohort, only clinical stage, ER status and pCR remained independently associated with DFS. Notably, subset analysis showed that lumpectomy was independently associated with improved TTR (HR 0.40; 95% CI 0.17-0.97) in the triple negative group only, but this did not translate into improved DFS with lumpectomy in this group. Radiographic CR as determined by breast MRI accurately predicted presence or absence of pCR in 74% of cases, but was not independently associated with DFS, OS or TTP. Conclusions:Among a contemporary cohort of women receiving neoadjuvant systemic therapy and breast MR imaging at 9 NCI designated cancer centers, type of surgery did not impact DFS, OS or TTP. The only exception was found in the triple negative group in which the lumpectomy group had a more favorable TTP compared to the mastectomy group. These findings provide additional evidence that in women who are appropriate candidates for lumpectomy after NCT, BCT does not compromise long-term cancer outcomes. Citation Format: De Los Santos J, Hyslop T, Alvarado M, Forero A, Golshan M, Hieken T, Horton J, Hudis C, McGuire K, Meric-Bernstam F, Nanda R, Zagar T, Hwang S. Treatment outcomes in patients with invasive breast cancer treated with neoadjuvant systemic therapy and breast MR imaging: Results of a secondary analysis of TBCRC 017. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr S3-06.

Abstract Background: Retrospective studies suggest that primary breast surgery is associated with improved overall survival (OS) in Stage IV breast cancer. TBCRC 013 is a multi-center prospective registry study evaluating the role of surgery for the primary tumor in Stage IV disease. Methods: From 7/09 - 4/12, 128 eligible pts from 14 sites were enrolled in two cohorts (A: Stage IV with intact primary tumor (n = 112); B: metastases (mets) within 3 months of primary surgery (n = 16)). Baseline patient and tumor characteristics, and surgery of the primary were correlated with 2yr overall survival (OS) using log rank, Kaplan Meier and Cox regression for all patients. Comparisons were also made between cohorts A and B and within cohort A stratified by response to systemic therapy. Responders included those with any response (partial,complete) or stable disease at distant sites. Results: Median pt age was 52yrs(21-79) and median primary tumor size 3.2cm(0.7-15). Phenotypes were ER+ 106 (83%), HER2neg 91(71%), and triple neg 10(8%). 60(47%) had bone-only mets. The only significant baseline difference between cohorts A and B was the presence of palpable nodes (A:62% vs B:0%, p<0.001). There were no differences in age, tumor size, ECOG scores, ER or HER2 status, number or sites of mets between cohorts A and B. At a median follow-up of 25 mo (95%CI, 23-31), 2yr OS for all pts is 86% (80-92) and is superior in cohort B as compared to A, (100% vs 84%, p = 0.03). On multivariate analysis (MVA) including all pts, only surgery, ER and HER2 positivity were associated with improved OS (table). Among 112 pts with an intact primary (Arm A), 17(15%) were non-responsive (NR) to systemic therapy, 3(18%) of whom required palliative surgery at a median time of 10.4mos. 2yr OS among NR was 33% (15-69) as compared to 94% (88-99) in Arm A responders (R) (p<0.001). ER positivity was the only baseline difference between NR (65%) and R (88%) within Arm A (p = 0.02). Among 94(85%) Arm A responders, 39(41%) had elective surgery (median 8.4 mos, 95%CI:6.9-10.3) and only 1 of the remaining 47(2%) required palliation. When limited to Arm A responders, elective surgery was not associated with improved 2yr OS (surgery vs not: 94% vs 92%, p = 0.5). Median time to progression following elective surgery was 12 mos (95%CI,8-19mos). When cohort B (n = 16) and cohort A surgery groups (n = 39) are combined, surgery of the primary tumor is associated with improved 2yr OS (96% vs 74%, p = 0.002). Conclusions: In this prospective registry study, patients diagnosed with mets within 3 months of primary breast surgery have an improved 2yr OS. When all pts having surgery (A + B) are examined, surgery is associated with improved OS on MVA, but when limited to Arm A responders, elective surgery does not improve OS. Given that the number of Arm A responders is small, results from the prospective randomized trial will be needed to address this question. These data also demonstrate that the need for surgical palliation of the primary tumor is uncommon in the modern era. Multivariate Analysis for OSN = 128HR Death (95%CI)pvalueSurgery0.28 (0.10-0.74)0.01ER positivity0.28 (0.10-0.72)0.01HER2 positivity0.21 (0.06-0.74)0.01MVA included: age, tumor size, ECOG, ER, PR, HER2, met sites, and surgery Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-18-09.