Citations

Abstract Background: NET is offered to postmenopausal patients (pts) with clinical stage 2/3 ER+/HER2- BC to promote breast-conserving surgery. Also limited surgical accessibility during the COVID19 pandemic has increased NET utility. Inability to identify ET-resistant disease at diagnosis risks disease progression (PD) and delays more effective treatments. Dowsett et al. recently demonstrated that baseline levels of ER, progesterone receptor (PR), Ki67 (>15% vs ≤15%), and Ki67 (>10% vs ≤10%) 2-4 weeks (wks) after starting NET may improve appropriate patient (pt) selection for NET (PMC7280290). The ER, PR and Ki67-based prediction model divides pts with primary ER+/HER2- BC into 3 groups for appropriateness for NET: (Group 1) NET is likely to be inappropriate (Allred ER <6 or ER 6 and PgR <6), (Group 2) NET may be appropriate and a biopsy for on-treatment Ki67 analysis may be considered after 2-4 wks of NET (2A: ER 7 or 8 and PgR <6 and 2B: ER 6 or 7 and PgR ≥6) given that on-treatment Ki67 >10% has been associated with worse outcome (PMC5455353), or (Group 3) NET is appropriate (ER 8 and PgR ≥6). The ALTERNATE trial (NCT01953588) randomized postmenopausal women with clinical stage II or III, ER+ (Allred score 6-8)/HER2- BC to receive anastrozole (ANA), fulvestrant (FUL), or ANA + FUL for 6 months, unless Ki67 was >10% on wk 4 or 12 biopsy, in which case pts were triaged to receive neoadjuvant chemotherapy (NCT) or surgery. As previously reported, the ET-sensitive disease (mPEPI 0 plus pCR) rates were similar across the treatment arms and overall 22% (286 of 1,299) pts had Ki67 >10% at wk 4 or 12. The ALTERNATE trial therefore provides a large independent data set to evaluate the NET appropriateness model. Results: Among 1,299 eligible pts randomized to receive 6 months of NET, 214 were excluded due to absent HR Allred score (n=41) or absence of pre-treatment and wk 4 Ki67 determinations (n=173). The proportions of the remaining 1,085 pts in Group 1, 2 and 3 were 1% (n=10), 43% (n= 468), and 56% (n=607), respectively. On-study Ki67 >10% prompting conversion from NET to NCT/Surgery occurred in: Group 1 90% (9 of 10), Group 2 30% (141 of 468), and Group 3 17% (104 of 607) (Table 1). Among the 1,075 pts in Groups 2 and 3, 260 (24%) pts had Ki67 ≤15% at baseline (BL), among whom only 14 (5.4%) had Ki67 >10% at wk 4, compared to 231 of the 815 (28.3%) who had BL Ki67 >15% and subsequent Ki67 >10% at wk 4. 2% of pts who remained on NET due to on-treatment Ki67 <10% had PD. Response and PEPI-0 rates by group will be reported. Conclusion: ALTERNATE trial data support a model whereby levels of ER, PR and Ki67 at diagnosis can be used for the identification of postmenopausal pts with primary ER+/HER2- BC who are appropriate for NET. When baseline ER Allred scores are >6 and Ki67 ≤15%, there is a low likelihood of ET-resistant disease. When BL Ki67 is >15%, ET sensitivity is variable, and on-treatment biopsy for Ki67 may assist in triaging regarding NET appropriateness, particularly given the extremely low local PD rates seen in ALTERNATE when on-treatment Ki67 was <10%. Support: U10CA180821, U10CA180882, U24CA196171, UG1CA189856, U10CA180868 (NRG); NCI BIQSFP, BCRF, Genentech, AstraZeneca. https://acknowledgments.alliancefound.org; Clinical Trials.gov Identifier: NCT01953588 Table 1 Baseline levels of ER, PR, and Ki67 in Relation to Wk 4 Ki67 (N=1,085)BaselineWeek 4GroupNERAllred ScorePRAllred ScoreKi67Ki67 ≤10%N (%)Ki67 >10%N (%)1N=26<6≤15%0 (0%)2 (100%)9 (90)N=86<6>15%1 (12.5%)7 (87.5%)2AN=647 or 8<6≤15%61 (95.3%)3 (4.7%)90 (30.1)N=2357 or 8<6>15%148 (63%)87 (37%)2BN=466 or 7≥6≤15%42 (91.3%)4 (8.7%)51 (30.2)N=1236 or 7≥6>15%76 (61.8%)47 (38.2%)3N=1508≥6≤15%143 (95.3%)7 (4.7%)104 (17.1)N=4578≥6>15%360 (78.8%)97 (21.2%) Citation Format: Matthew J Ellis, Vera Suman, A. Marilyn Leitch, Souzan Sanati, Kiran Vij, Gary W Unzeitig, Jeremy Hoog, Mark Watson, Olwen Hahn, Joseph Guenther, Abigail Caudle, Erika Crouch, Horacio Maluf, Mitch Dowsett, Amy Tiersten, Monica Mita, Wajeeha Razaq, Tina J Hieken, Yang Wang, Travis Dockter, Jo Anne Zujewski, Anna Weiss, Clifford Hudis, Eric P Winer, Kelly Hunt, Ann H Partridge, Cynthia X Ma, Lisa A Carey. Validation of a predictive model for potential response to neoadjuvant endocrine therapy (NET) in postmenopausal women with clinical stage II or III estrogen receptor positive (ER+) and HER2 negative (HER2-) breast cancer (BC): An ALTERNATE trial analysis (Alliance A011106) [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PD2-10.

Abstract Background: Young age at diagnosis is an independent risk factor for recurrence and death from breast cancer (BC), with the greatest impact of young age demonstrated in hormone receptor positive (HR+) disease. Younger women are less likely to be adherent to endocrine therapy (ET), which may contribute to disparate outcomes. Methods: As part of a prospective cohort that enrolled women with BC diagnosed at age ≤40 between 2006-2016, we identified women with HR+, Stage I-III BC. Serial surveys with items assessing socio-demographic and treatment information including medication use are administered 1-2 times per year. Medical record review was used to ascertain stage and HR status and to confirm recurrent disease (locoregional, distant, or new primary breast cancer). Women who initiated ET but discontinued it <5-years post-diagnosis without resumption were classified as non-persistent. Univariable and multivariable regression models were fit to identify predictors of non-persistence and recurrence.Results: Among 607 women who initiated ET (median age at diagnosis: 36, range:17-40; 38%, 45%, 17% were Stage 1, 2, and 3, respectively).16% (99/607) were non-persistent, of whom 30% (30/99) discontinued ET ≤2 years post-diagnosis and over half had discontinued (54%, 54/99) by 3 years. In multivariable regression, those who were younger at diagnosis (age ≤30 vs. 36-40: OR: 3.39, 95% CI: 1.84-6.24; age 31-36 vs. 36-40: OR: 2.81 95% CI: 1.70-4.64) were more likely to discontinue ET while those with a higher stage at diagnosis were less likely to discontinue ET (Stage 2 vs. 1: OR: 0.46, 95% CI: 0.29-0.74; Stage 3 vs 1: OR: 0.32, 95% CI: 0.15-0.68). At a median follow-up time from diagnosis of 7.8 years (range 1-13 years), 15% of women (88/607) recurred or developed a new primary BC at a median time from diagnosis of 3.5 years (range 1-12 years). Of these, 66% (58/88) were distant recurrences, 32% (28/88) loco-regional, and 2% (2/88) new primary BCs. Rates of recurrence were higher among women who were persistent (81/508, 16%) vs. non-persistent (7/99, 7%, p=0.02). In multivariable regression, those who were non-persistent were less likely to recur (OR: 0.43, 95% CI: 0.19-0.98) while those with a higher stage were more likely to recur (Stage 3 vs. 1: OR: 2.36, 95% CI: 1.03-5.41). Sociodemographic, patient, and other treatment factors did not predict recurrence. Conclusions: Approximately 16% of young women with HR+ BC stop ET earlier than indicated, however non-persistence was not a risk factor for BC recurrence a median of 8 years following diagnosis in our cohort. Importantly, women with higher risk disease who are likely to benefit most from adherence to ET were less likely to discontinue treatment. Extended follow-up will further inform the impact of non-persistence on the incidence of late recurrences for which women with HR+ BC are at increased risk. Citation Format: Shoshana M Rosenberg, Yue Zheng, Philip Poorvu, Kathryn Ruddy, Rachel Gaither, Rulla Tamimi, Lidia Schapira, Jeffrey Peppercorn, Steven Come, Virginia Borges, Ann Partridge. Endocrine therapy non-persistence and recurrence in young women with early stage breast cancer [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PD2-08.

Abstract Background: Ki67 values >10% 2-4 weeks (wks) after starting neoadjuvant ET (NET) indicates persistent cell proliferation, resistance to ET, and is associated with increased risk of recurrence. The ACOSOG Z1031 trial suggested that these tumors are also relatively chemotherapy (chemo) resistant with a low pathologic complete response (pCR) rate to NCT. The ALTERNATE trial (NCT01953588) is a randomized study of neoadjuvant anastrozole (ANA), fulvestrant (FUL), or ANA + FUL in postmenopausal patients (pt) with newly diagnosed clinical stage II or III ER+ (Allred score 6-8)/HER2- BC. Ki67 >10% at wk 4 or 12 after starting NET triggered triage to NCT of physician choice or weekly paclitaxel. Pts who refused protocol-directed therapy, were not candidates for NCT, or decided to undergo immediate surgery are being followed per protocol. Here we report the rates of pCR and residual cancer burden (RCB) following NCT for pts triaged to NCT due to Ki67 >10% at wk 4 or 12. Results: Of the 1,299 eligible pts randomized to receive ANA, FUL, or ANA + FUL, 286 (22%) had Ki67 >10% at wk 4 or 12. 168 of these 286 pts (58.7%) chose to switch to NCT, 32 went to surgery (11.2%), and 86 discontinued further protocol-directed therapy (30.1%). Among the 168 pts who underwent NCT, the presenting clinical T stages were cT2 (n=113; 67.26%), cT3 (n=47; 27.98%) and cT4 (n=8; 4.76%) and N stages were cN0 (n=82; 48.8%), cN1 (n=75; 44.6%), cN2/3 (n=9; 5.4%) and cNx (n=2; 1.2%). Central ER testing was performed on pre-treatment biopsies and confirmed ER Allred score 6-8 in 155 of 168 (92.2%) pts, with the rest being ER Allred score 4-5 (n=5; 3%), ER- (Allred score 0) (n=2; 1.2%), or not tested (n=6; 3.6%). Most (n=139; 82.7%) were ER+/PR+, while 17.3% (n=29) were ER+/PR-, and tumor grades were G1 (n=10; 6%), G2 (n=99; 58.9%), G3 (n=54; 32.1%), not reported (n=5; 3%). Baseline Ki67 levels prior to NET were >10% in 94% (n=158), ≤10% in 3% (n=5), and not done in 3% (n=5). NCT regimens administered included doxorubicin/cyclophosphamide (AC) followed by paclitaxel (T) (n=60; 35.71%); weekly paclitaxel (n=56; 33.33%), docetaxel/cyclophosphamide (TC) (n=33; 19.65%), other doxorubicin and/or taxane containing regimen (n=17; 10.12%), and cyclophosphamide/methotrexate/fluorouracil (CMF) (n=2; 1.19%). 35 (20.8%) pts did not complete planned course of NCT due to toxicity (n=27) or refusal (n=8). 154 NCT pts underwent surgery (mastectomy in 40.3%, and breast conserving surgery in 59.7%). The path ypT stages were Tis/0 (n=10; 6.5%), T1 (n=62; 40.3%), T2 (n=61; 39.6%), and T3/4 (n=21; 13.6%), and the ypN stages were N0 (n=66; 42.9%), N1 (n=57; 37%), N2/3 (n=30; 19.5%), and Nx (n=1; 0.6%). Among the 168 pts who started on NCT (intent to treat population), there were 8 pCRs (no invasive disease in the breast or lymph nodes) (4.8%; 95% CI: 2.1% to 9.2%). Residual Cancer Burden (RCB) categories include RCB 0 (n=8; 4.8%), RCB 1 (n=15; 8.9%), RCB 2 (n=82; 48.8%), RCB 3 (n=42; 25.0%), and not determined (n=21; 12.5%). Correlations of baseline pt and tumor characteristics with pathology response to NCT will also be presented. Conclusion: In pts with NET-resistant ER+/HER2- BC, salvage NCT is not likely to induce a complete or near complete response. More effective treatments are needed for this high-risk ER+/HER2- pt population. Support: U10CA180821, U10CA180882, U24CA196171, UG1CA189856, U10CA180868 (NRG); NCI BIQSFP, BCRF, Genentech, AstraZeneca. https://acknowledgments.alliancefound.org. Clinical Trials.gov Identifier: NCT01953588 Citation Format: Cynthia X Ma, Vera Suman, A. Marilyn Leitch, Souzan Sanati, Kiran Vij, Gary W Unzeitig, Jeremy Hoog, Mark Watson, Olwen Hahn, Joseph Guenther, Abigail Caudle, Erika Crouch, Horacio Maluf, Amy Tiersten, Monica Mita, Wajeeha Razaq, Tina J Hieken, Yang Wang, Travis Dockter, Jo Anne Zujewski, Anna Weiss, Kelly Hunt, Clifford Hudis, Eric P Winer, Matthew J Ellis, Lisa A Carey, Ann H Partridge. Neoadjuvant chemotherapy (NCT) response in postmenopausal women with clinical stage II or III estrogen receptor positive (ER+) and HER2 negative (HER2-) breast cancer (BC) resistant to endocrine therapy (ET) in the ALTERNATE trial (Alliance A011106) [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr GS4-05.

Abstract Background: Pregnancy-related issues are a priority for young breast cancer (BC) patients. Increasing evidence has shown that pregnancy after prior BC diagnosis is feasible. Nevertheless, few BC survivors conceive following anticancer treatment completion and many physicians remain concerned about the potentially detrimental effects of pregnancy after BC in terms of fetal/obstetrical outcomes and maternal prognosis. This systematic review and meta-analysis aims at providing updated and solid evidence on these important issues. Methods: A systematic literature review up to January 31, 2020 with no language restriction was conducted to identify studies including patients with a pregnancy after prior BC diagnosis. Chances of pregnancy after BC, fetal and obstetrical outcomes, disease-free survival (DFS) and overall survival (OS) were assessed. Pooled relative risks (RRs), hazard ratios (HRs) or odds ratio (ORs) with 95% confidence intervals (CI) were calculated using the random effects models. The study is registered with the PROSPERO registration number CRD42020158324. Results: Overall, 39 studies were included. Out of the 8,265,713 young women included in these studies, 8,093,401 were from the general population, 57,739 had cancers other than BC, 114,573 had BC. Among the 114,573 BC patients, 7,505 had a pregnancy after BC diagnosis and 107,068 did not. Compared to women from the general population, BC patients had 60% reduced chances of having a pregnancy following anticancer treatment completion (RR 0.40, 95% CI 0.32-0.49). Among other cancer patients, only women with prior cervical cancer had lower pregnancy rates (RR 0.33, 95% CI 0.31-0.35) than BC patients. Compared to the general population, BC survivors had significantly increased risks of low birth weight (OR 1.50, 95% CI 1.31-1.73), small for gestational age (OR 1.16, 95% CI 1.01-1.33), preterm delivery (OR 1.45, 95% CI 1.11-1.88) and caesarean section (OR 1.14, 95% CI 1.04-1.25). No significant increased risk of congenital abnormalities (OR 1.63, 95% CI 0.89-2.98) or other pregnancy or delivery complications (spontaneous or induced abortion, gestosis, antepartum or postpartum hemorrhage) was observed. Prior chemotherapy exposure or short pregnancy interval (defined as <2 or <5 years after BC diagnosis) were not associated with additional increased risk of complications. Pregnancy after BC was not associated with a negative impact on patients’ outcomes. Compared to BC patients without subsequent pregnancy, those with pregnancy after BC had better OS (HR 0.56, 95% CI 0.46-0.67) and DFS (HR 0.73, 95% CI 0.56-0.94). Similar results were observed in the studies correcting for the potential “healthy mother effect” (OS: HR 0.52, 95% CI 0.42-0.65; DFS: HR 0.74, 95% CI 0.58-0.96). No detrimental prognostic effect of pregnancy after BC was observed in patients with hormone-receptor positive disease (DFS: HR 1.10, 95% CI 0.73-1.66), while better outcomes were observed for those with hormone-receptor negative disease (DFS: HR 0.72, 95% CI 0.55-0.95). The safety of pregnancy after BC was observed irrespective of BRCA status, nodal status, previous chemotherapy exposure, pregnancy interval and pregnancy outcomes. Conclusions: This large meta-analysis provides solid evidence on the safety of pregnancy after prior BC diagnosis. The increased risk of fetal and obstetrical complications (but not of congenital abnormalities) calls for ensuring a closer monitoring of these pregnancies. The significantly reduced chances of conceiving as compared to the general population and other cancer patients should raise further awareness on the need to improve the oncofertility counseling of young BC patients wishing to complete their family planning following anticancer treatment completion. Citation Format: Eva Blondeaux, Marta Perachino, Marco Bruzzone, Richard A. Anderson, Evandro De Azambuja, Philip D. Poorvu, Hee Jeong Kim, Cynthia Villarreal-Garza, Barbara Pistilli, Ines Vaz-Luis, Cristina Saura, Kathryn J. Ruddy, Maria Alice Franzoi, Chiara Sertoli, Marcello Ceppi, Hatem A. Azim, Jr., Frederic Amant, Isabelle Demeestere, Lucia Del Mastro, Ann H. Partridge, Olivia Pagani, Fedro A. Peccatori, Matteo Lambertini. Chances of pregnancy after breast cancer, reproductive and disease outcomes: A systematic review and meta-analysis [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr GS3-09.

Objective: We aimed to investigate eligibility for breast conserving surgery (BCS) pre- and post-neoadjuvant systemic therapy (NST), and trends in the surgical treatment of young breast cancer patients. Background: Young women with breast cancer are more likely to present with larger tumors and aggressive phenotypes, and may benefit from NST. Little is known about how response to NST influences surgical decisions in young women. Methods: The Young Women's Breast Cancer Study, a multicenter prospective cohort of women diagnosed with breast cancer at age ≤40, enrolled 1302 patients from 2006 to 2016. Disease characteristics, surgical recommendations, and reasons for choosing mastectomy among BCS-eligible patients were obtained through the medical record. Trends in use of NST, rate of clinical and pathologic complete response, and surgery were also assessed. Results: Of 1117 women with unilateral stage I-III breast cancer, 315 (28%) received NST. Pre-NST, 26% were BCS eligible, 17% were borderline eligible, and 55% were ineligible. After NST, BCS eligibility increased from 26% to 42% (P < 0.0001). Among BCS-eligible patients after NST (n = 133), 41% chose mastectomy with reasons being patient preference (53%), BRCA or TP53 mutation (35%), and family history (5%). From 2006 to 2016, the rates of NST (P = 0.0012), clinical complete response (P < 0.0001), and bilateral mastectomy (P < 0.0001) increased, but the rate of BCS did not increase (P = 0.34). Conclusion: While the proportion of young women eligible for BCS increased after NST, many patients chose mastectomy, suggesting that surgical decisions are often driven by factors beyond extent of disease and treatment response.

BackgroundMany young women with newly diagnosed breast cancer are interested in future pregnancies. Prospective data regarding fertility interest and reproductive patterns after diagnosis are needed to counsel patients.MethodsThe Young Women's Breast Cancer Study is a multicenter, prospective cohort of women who were diagnosed with breast cancer at age ≤40 years between 2006 and 2016. Women complete surveys at baseline, every 6 months for 3 years, then annually. Here, the authors describe fertility interest and pregnancies within 5 years of diagnosis for women with stage 0 through III breast cancer.ResultsOf 1026 eligible participants, 368 (36%) reported interest in future biologic children at least once within 5 years after diagnosis, including 16% at 5 years after diagnosis. Among 130 women who attempted to become pregnant, 90 (69.2%) conceived; and, among 896 women who did not attempt to conceive, 18 (2.0%) became pregnant, with a total of 152 pregnancies resulting in 91 live births. Factors associated with pregnancy included younger versus older age at diagnosis (aged ≤30 vs 36‐40 years: odds ratio [OR], 6.63; 95% CI, 3.18‐13.83; P < .0001; aged 31‐35 vs 36‐40 years: OR, 5.86; 95% CI, 3.37‐10.17; P < .0001) and being nulliparous versus parous (OR, 2.66; 95% CI, 1.56‐4.53; P = .001). The receipt of endocrine therapy versus no endocrine therapy (OR, 0.35; 95% CI, 0.20‐0.59; P = .001) was inversely associated with pregnancy.ConclusionsMany women remain interested in future fertility in the 4 years after a breast cancer diagnosis, indicating that longitudinal fertility discussions are needed. Although a minority of those interested in having children attempted to become pregnant in the first 5 years, most who attempted to conceive did so and had live births.

Abstract Antimullerian hormone (AMH) is a promising biomarker for ovarian reserve. In this study, we assessed AMH before and 1 year after initiation of adjuvant chemotherapy on National Surgical Adjuvant Breast and Bowel Project (NSABP)/NRG Oncology B-47 in female participants aged 42 years and younger (median age = 39 years). At baseline, median AMH was 1.2 ng/mL; 13 (4.7%) values were less than 0.1 ng/mL (the threshold for detectable levels, in the perimenopause and menopause range), and 57 values (20.6%) were less than 0.5 ng/mL. At 1 year, 215 (77.6%) were less than 0.1 ng/mL, and 264 (95.3%) were less than 0.5 ng/mL. Postchemotherapy menses were reported by 46.2% of participants. Multivariable logistic regression found that the odds of having postchemotherapy menses increased with younger age, higher body mass index, and higher prechemotherapy AMH, but not by trastuzumab administration or by the choice of chemotherapy (doxorubicin-cyclophosphamide followed by paclitaxel vs docetaxel-cyclophosphamide). We conclude that higher prechemotherapy AMH predicts a lower risk of chemotherapy-induced amenorrhea and that AMH 1 year after chemotherapy initiation is not informative in this setting because it is likely to be very low.

PURPOSE CALGB 40601 assessed whether dual versus single human epidermal growth factor receptor 2 (HER2) –targeting drugs added to neoadjuvant chemotherapy increased pathologic complete response (pCR). Here, we report relapse-free survival (RFS), overall survival (OS), and gene expression signatures that predict pCR and survival. PATIENTS AND METHODS Three hundred five women with untreated stage II and III HER2-positive breast cancer were randomly assigned to receive weekly paclitaxel combined with trastuzumab plus lapatinib (THL), trastuzumab (TH), or lapatinib (TL). The primary end point was pCR, and secondary end points included RFS, OS, and gene expression analyses. mRNA sequencing was performed on 264 pretreatment samples. RESULTS One hundred eighteen patients were randomly allocated to THL, 120 to TH, and 67 to TL. At more than 7 years of follow-up, THL had significantly better RFS and OS than did TH (RFS hazard ratio, 0.32; 95% CI, 0.14 to 0.71; P = .005; OS hazard ratio, 0.34; 95% CI, 0.12 to 0.94; P = .037), with no difference between TH and TL. Of 688 previously described gene expression signatures, significant associations were found in 215 with pCR, 45 with RFS, and only 22 with both pCR and RFS (3.2%). Specifically, eight immune signatures were significantly correlated with a higher pCR rate and better RFS. Among patients with residual disease, the immunoglobulin G signature was an independent, good prognostic factor, whereas the HER2-enriched signature, which was associated with a higher pCR rate, showed a significantly shorter RFS. CONCLUSION In CALGB 40601, dual HER2-targeting resulted in significant RFS and OS benefits. Integration of intrinsic subtype and immune signatures allowed for the prediction of pCR and RFS, both overall and within the residual disease group. These approaches may provide means for rational escalation and de-escalation treatment strategies in HER2-positive breast cancer.