p4EBP1 staining predicts outcome in ER-positive endocrine-resistant metastatic breast cancer patients treated with everolimus and exemestane

BACKGROUND

To identify patients most likely to respond to everolimus, a mammalian target of rapamycin (mTOR) inhibitor, a prospective biomarker study was conducted in hormone receptor-positive endocrine-resistant metastatic breast cancer patients treated with exemestane-everolimus therapy.

METHODS

Metastatic tumor biopsies were processed for immunohistochemical staining (p4EBP1, PTEN, pAKT, LKB1, and pS6K). ESR1, PIK3CA and AKT1 gene mutations were detected by NGS. The primary endpoint was the association between the p4EBP1 expression and clinical benefit rate (CBR) at 6 months of everolimus plus exemestane treatment.

RESULTS

Of 150 patients included, 107 were evaluable for the primary endpoint. p4EBP1 staining above the median (Allred score ≥6) was associated with a higher CBR at 6 months (62% versus 40% in high-p4EBP1 versus low-p4EBP1, χ2 test, p = 0.026) and a longer progression-free survival (PFS) (median PFS of 9.2 versus 5.8 months in high-p4EBP1 versus low-p4EBP1; p = 0.02). When tested with other biomarkers, only p4EBP1 remained a significant predictive marker of PFS in multivariate analysis (hazard ratio, 0.591; p = 0.01).

CONCLUSIONS

This study identified a subset of patients with hormone receptor-positive endocrine-resistant metastatic breast cancer and poor outcome who would derive less benefit from everolimus and exemestane. p4EBP1 may be a useful predictive biomarker in routine clinical practice.

CLINICAL TRIAL REGISTRATION

NCT02444390.

Dynamics of Long-Term Patient-Reported Quality of Life and Health Behaviors After Adjuvant Breast Cancer Chemotherapy

We aimed to characterize long-term quality of life (QOL) trajectories among patients with breast cancer treated with adjuvant chemotherapy and to identify related patterns of health behaviors.

Long-Term Longitudinal Patterns of Patient-Reported Fatigue After Breast Cancer: A Group-Based Trajectory Analysis

PURPOSE

Fatigue is recognized as one of the most burdensome and long-lasting adverse effects of cancer and cancer treatment. We aimed to characterize long-term fatigue trajectories among breast cancer survivors.

METHODS

We performed a detailed longitudinal analysis of fatigue using a large ongoing national prospective clinical study (CANcer TOxicity, ClinicalTrials.gov identifier: NCT01993498) of patients with stage I-III breast cancer treated from 2012 to 2015. Fatigue was assessed at diagnosis and year 1, 2, and 4 postdiagnosis. Baseline clinical, sociodemographic, behavioral, tumor-related, and treatment-related characteristics were available. Trajectories of fatigue and risk factors of trajectory-group membership were identified by iterative estimates of group-based trajectory models.

RESULTS

Three trajectory groups were identified for severe global fatigue (n = 4,173). Twenty-one percent of patients were in the high-risk group, having risk estimates of severe global fatigue of 94.8% (95% CI, 86.6 to 100.0) at diagnosis and 64.6% (95% CI, 59.2 to 70.1) at year 4; 19% of patients clustered in the deteriorating group with risk estimates of severe global fatigue of 13.8% (95% CI, 6.7 to 20.9) at diagnosis and 64.5% (95% CI, 57.3 to 71.8) at year 4; 60% were in the low-risk group with risk estimates of 3.6% (95% CI, 2.5 to 4.7) at diagnosis and 9.6% (95% CI, 7.5 to 11.7) at year 4. The distinct dimensions of fatigue clustered in different trajectory groups than those identified by severe global fatigue, being differentially affected by sociodemographic, clinical, and treatment-related factors.

CONCLUSION

Our findings highlight the multidimensional nature of cancer-related fatigue and the complexity of its risk factors. This study helps to identify patients with increased risk of severe fatigue and to inform personalized interventions to ameliorate this problem.

A phase III randomized trial of weight loss to reduce cancer-related fatigue among overweight and obese breast cancer patients: MEDEA Study design

Background

Elevated body mass index (BMI) represents a risk factor for cancer-related fatigue (CRF). Weight loss interventions are feasible and safe in cancer survivors, leading to improved cardio-metabolic and quality of life (QOL) outcomes and modulating inflammatory biomarkers. Randomized data are lacking showing that a lifestyle intervention aimed at weight loss, combining improved diet, exercise, and motivational counseling, reduces CRF. Motivating to Exercise and Diet, and Educating to healthy behaviors After breast cancer (MEDEA) is a multi-center, randomized controlled trial evaluating the impact of weight loss on CRF in overweight or obese survivors of breast cancer. Herein, we described the MEDEA methodology.

Methods

Patients (N = 220) with stage I–III breast cancer and BMI ≥ 25 kg/m², within 12 months of primary treatment, and able to walk ≥ 400 m are eligible to enroll. Participants are randomized 1:1 to health education alone vs. a personalized telephone-based weight loss intervention plus health education. Both arms receive a health education program focusing on healthy living. Patients in the intervention arm are paired with an individual lifestyle coach, who delivers the intervention through 24 semi-structured telephone calls over 1 year. Intervention goals include weight loss ≥ 10% of baseline, caloric restriction of 500–1000 Kcal/day, and increased physical activity (PA) to 150 (initial phase) and 225–300 min/week (maintenance phase). The intervention is based on the social cognitive theory and is adapted from the Breast Cancer Weight Loss trial (BWEL, A011401). The primary endpoint is the difference in self-reported CRF (EORTC QLQ-C30) between arms. Secondary endpoints include the following: QOL (EORTC QLQ-C30, -BR45, -FA12), anxiety, and depression (HADS); weight and BMI, dietary habits and quality, PA, and sleep; health care costs (hospital-admissions, all-drug consumption, sick leaves) and cost-effectiveness (cost per quality-adjusted life-year); and patient motivation and satisfaction. The primary analysis of MEDEA will compare self-reported CRF at 12 months post-randomization between arms, with 80.0% power (two-sided α = 0.05) to detect a standardized effect size of 0.40.

Discussion

MEDEA will test the impact of a weight loss intervention on CRF among overweight or obese BC survivors, potentially providing additional management strategies and contributing to establish weight loss support as a new standard of clinical care.

Trial registration

ClinicalTrials.govNCT04304924

Abstract P2-13-27: Infusion-related reactions in patients receiving pertuzumab and trastuzumab: A retrospective study

BACKGROUND: The use of two anti-HER2 monoclonal antibodies (mAbs) (pertuzumab and trastuzumab) combined with taxanes is the standard of care for first line treatment in HER2-positive metastatic breast cancer (mBC). Infusion related reactions (IRR) during first administration of anti-HER2 mAb have been reported. Reintroduction of the causal drugs is often possible, but there is no data to identify patients at highest risk of developing IRR and modalities of safe reintroduction. The aim of this study was to report patients who experienced IRR during anti-HER2 mAbs infusions at Institut Curie Hospitals (ICH) and to describe these reactions. METHODS: All IRR cases must be reported to the ICH pharmacies. We retrospectively inspected the electronic record of patients who experienced an IRR during pertuzumab (Pmab) and trastuzumab (Tmab). We collected patients’ characteristics, grade of IRR and outcomes. RESULTS: From January 2013 to December 2020, a total of 223 patients had at least one Pmab+Tmab infusion as part of their BC treatment. Among them, 28 patients (8%) with anti-HER2 mAb IRR were identified. All patients but one had an HER2-positive BC; the HER2-negative case was a HER3-mutant mBC. Twelve patients (43%) had de novo mBC. Twenty-six patients (93%) received Pmab+Tmab as first line treatment for mBC. Ten patients were previously exposed to Tmab and three to Pmab+Tmab for (neo)adjuvant treatment. At IRR onset, 21 patients (75%) had liver metastasis, with more than five liver metastases for 19 of them. Fifteen patients (55%) had liver enzymes upper normal limit. IRR occurred during first anti-HER2-mAb infusion in 22 patients (79%) despite pre-treatment with antihistaminic and/or glucosteroids for taxanes. The other IRR were reported at the 2nd, 5th, 6th, 8th and > 10th cycle of Pmab+Tmab. Sixteen IRR (57%) were attributed to Pmab infusion, 9 (32%) to Tmab infusion and 3 (11%) to Tmab and/or Pmab. Al IRR were declared to the pharmacovigilance agency. Majority of reactions were mild to moderate (54% of grade 2). Most frequent symptoms associated with IRR were: thrills (68%), hyperthermia (64%); low oxygen saturation (36%), pain (25%), hypotension (21%), cutaneous (18%) and digestive (18%) reaction. Three patients were transferred to ICU. One death was attributed to anti-HER2 mAb IRR (death was attributed to respiratory distress during the first Tmab infusion). Reintroduction off Pmab+Tmab was performed in 18 patients, after pre-treatment with antihistaminic and/or glucosteroids and with vital function monitoring in conventional hospitalization. No recurrence of IRR was observed in 15/18 patients. For the 3 patients with recurrent IRR, symptoms were mild to moderate. Objective response to anti-HER2 treatments was observed in twenty three patients (82%; 8 complete responses; 15 partial responses). Median PFS was 16 months. CONCLUSIONS: Most anti-Her2-mAb IRR occurs during first infusion, are mild to moderate and do not require a transfer in ICU. Our study suggests that patients with high liver burden might be over-represented among those experiencing an IRR. Reintroduction of Pmab+Tmab was safe in most patients, allowing the continuation of the anti-HER2 dual blockade.

Citation Format: Delphine Loirat, Juliette Logeart, Pauline Vaflard, Aurélien Noret, Mathilde Saint-Ghislain, Edith Borcoman, Audrey Hurgon, Cyrille Cros, Thomas Genevee, Audrey Bellesoeur, Francesco Ricci, Florence Lerebours, Laurence Escalup, Marie-Paule Sablin, François-Clément Bidard, Paul H. Cottu, Jean-Yves Pierga. Infusion-related reactions in patients receiving pertuzumab and trastuzumab: A retrospective study [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P2-13-27.

Results of TRIO-14, a phase II, multicenter, randomized, placebo-controlled trial of carboplatin-paclitaxel versus carboplatin-paclitaxel-ganitumab in newly diagnosed epithelial ovarian cancer

PURPOSE

Insulin-like growth factor (IGF) signaling is implicated in pathogenesis and chemotherapy resistance of epithelial ovarian cancer (EOC). We explored efficacy and safety of adding ganitumab, a monoclonal antibody targeting IGF-1R, to carboplatin/paclitaxel (CP) chemotherapy in patients with primary EOC.

DESIGN

Patients were randomly assigned to receive CP/ganitumab (18 mg/kg q3w) or CP/placebo for 6 cycles followed by 6 cycles of single agent ganitumab/placebo maintenance therapy as front-line therapy. Primary endpoint was progression free survival. Secondary endpoints were time to progression and overall survival. Pretreatment samples were prospectively collected for retrospective biomarker analyses.

RESULTS

170 patients enrolled. 165 patients assessable for toxicity. Median PFS was 15.7 months with CP/ganitumab and 16.7 months with CP/placebo (HR 1.23; 95% CI 0.82-1.83, P = 0.313). All grade neutropenia (84.1% vs 71.4%), thrombocytopenia (75.3% vs 57.1%) and hyperglycemia (15.9% vs 2.6%) were more common in the ganitumab group compared to the placebo group. Ganitumab/placebo related serious adverse events were reported in 26.1% of the patients with ganitumab and in 6.5% with placebo. Non-progression related fatal events were more common with ganitumab (5 versus 2 patients). The ganitumab group experienced more dose delays which resulted in lower relative dose intensity of chemotherapy in the experimental group. In an exploratory model IGFBP2 expression was predictive of ganitumab response (treatment interaction; PFS, P = 0.03; OS, P = 0.01).

CONCLUSION

Addition of ganitumab to CP chemotherapy in primary EOC did not improve PFS. Our results do not support further study of ganitumab in unselected EOC patients.

Onapristone Extended Release: Safety Evaluation from Phase I-II Studies with an Emphasis on Hepatotoxicity

Introduction

Antiprogestins have demonstrated promising activity against breast and gynecological cancers, but liver-related safety concerns limited the advancement of this therapeutic class. Onapristone is a full progesterone receptor antagonist originally developed as an oral contraceptive and later evaluated in phase II studies for metastatic breast cancer. Because of liver enzyme elevations identified during clinical studies, further development was halted. Evaluation of antiprogestin pharmacology and pharmacokinetic data suggested that liver enzyme elevations might be related to off-target or metabolic effects associated with clinical drug exposure.

Objective

We explored whether the use of a pharmaceutic strategy targeting efficacious systemic dose concentrations, but with diminished peak serum concentrations and/or total drug exposure would mitigate hepatotoxicity. Twice-daily dosing of an extended-release formulation of onapristone was developed and clinically evaluated in light of renewed interest in antiprogestin therapy for treating progesterone receptor-positive breast and gynecologic cancers. The hepatotoxic potential of extended-release onapristone was assessed from two phase I–II studies involving patients with breast, ovarian, endometrial, and prostate cancer.

Results

Among the 88 patients in two phase I–II studies in progesterone receptor-positive malignancies treated with extended-release onapristone, elevated alanine aminotransferase/aspartate aminotransferase levels were found in 20% of patients with liver metastases compared with 6.3% without metastases. Of five patients with grade 3 or higher alanine aminotransferase elevations with or without bilirubin elevations (four with breast cancer and one with endometrial cancer), four were assessed as unrelated to extended-release onapristone by the safety data review committee. Furthermore, while the fifth patient’s liver enzyme elevations were considered possibly drug related by the study investigator, they were adjudicated as unlikely to be related (< 25% likelihood) by a subsequent independent hepatologist.

Conclusions

These results suggest that the extended-release formulation by reducing drug exposure may be associated with a reduced risk of hepatotoxicity, and supports the continued clinical evaluation of extended-release onapristone for treating progesterone receptor-positive cancers.

Alpelisib and fulvestrant efficacy in HR-positive HER2-negative PIK3CA-mutant advanced breast cancer: Data from the French early access program

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Background: In 11.2018, the PIK3CA-inhibitor alpelisib was made available in France through an early access program (EAP), in combination with fulvestrant in pre-treated PIK3CA-mutant, HR-positive, HER2-negative advanced breast cancer (ABC) patients. Patients had to received two or more prior systemic treatments for ABC, including an aromatase inhibitor and a CDK4/6 inhibitor in the absence of contraindications. This retrospective real-life, EAP-based study aimed to assess the efficacy and safety of alpelisib/fulvestrant combination in the post CDK4/6 inhibitor setting. Methods: The IRB-approved protocol and call for data were sent on 10.2020 to the cancer centers which participated the most in the EAP prospective registry. Eligible patients were women who started alpelisib/fulvestrant between 11. 2018 and 10.2020 as part of the EAP (which excluded patients with visceral crisis or inflammatory BC). Alpelisib and fulvestrant were used at standard doses. Primary endpoint was PFS by local investigators using RECIST1.1. Secondary endpoints included objective response rate and safety (NCI CTCAE v5.0). Results: 10 centers provided individual data regarding 209 consecutive patients. Patients had received a median number of 4 (1-14) previous systemic treatments for ABC, including CDK4/6 inhibitors, chemotherapy, fulvestrant (alone or in combination) and everolimus for 206 (98.8%), 159 (76.1%), 163 (78%) and 123 (58.8%) patients, respectively. With a median FU of 7.0 months, median PFS was 4.0 months (95%CI [3.5;5.0]) and 35.4% of 164 evaluable patients had an objective response. After stratification on the number of prior lines of treatment, prior exposure to everolimus had no impact on PFS (mPFS in the 123 patients pretreated with everolimus: 4.0m, 95%CI [3.5-5.5]). Of note, this population was enriched in patients who had a long disease control by everolimus (median time spent on everolimus: 7.0m, range (6.5-9.0)). In multivariable analysis, characteristics significantly associated with longer PFS were PS < 3 (HR = 0.03, 95%CI [0.02-0.29]) and prior treatment with fulvestrant (HR = 0.53, 95%CI [0.32-0.89]). N = 81(38.8%) patients discontinued alpelisib due to adverse events (AEs). Most frequent grade 3/4 AEs were hyperglycemia, skin rash, diarrhea and fatigue occurring in 13.4, 8.1, 4.8 and 1.9 % of patients, respectively. Conclusions: Despite heavy pre-treatments, alpelisib +fulvestrant had a clinically relevant efficacy in the French EAP population. Interestingly, prior treatment with either everolimus or fulvestrant did not overtly impair alpelisib-fulvestrant efficacy. The best treatment sequence for PI3KCA/mTOR inhibitors could be examined in future trials in PIK3CA-mutant ER+/HER2- ABC patients.

Abstract OT-38-01: MEDEA: A randomized trial of weight loss to reduce cancer-related fatigue (CRF) among overweight and obese breast cancer (BC) patients

Rationale: Overweight and obesity are highly prevalent among BC patients and are linked to poorer prognosis and worse patient-reported outcomes (PROs). Weight loss interventions, based on caloric restriction, increased physical activity (PA) and behavioral counselling, are safe and feasible among BC survivors and hold the promise to improve BC-specific outcomes. MEDEA: Motivating to Exercise and Diet, and Educating to healthy behaviors After breast cancer (ClinicalTrials.gov NCT04304924) will evaluate the impact of weight loss on CRF.

Trial design: French multi-center 1:1 randomized controlled trial comparing a 12-month personalized, telephone-based weight loss program + health education intervention vs health education alone in overweight or obese BC patients.

Endpoints and measures: Primary endpoint: difference in self-reported CRF 12 months post-randomization between arms, measured using the EORTC QLQ-C30 CRF subscale. Secondary endpoints: 1) PROs (EORTC QLQ-C30, -B45, -FA12), anxiety and depression (Hospital Anxiety and Depression Scale); 2) weight and body mass index (BMI), diet habits and quality, PA, sleep; 3) cost-effectiveness (number and length of hospital-admissions, all-drug consumption, number and duration of sick leaves). Accelerometer data will be collected to track PA and sleep measures. Qualitative analyses will evaluate patient motivation and satisfaction.

Main eligibility criteria: stage I-II-III BC, primary BC treatment completed within the prior 12 months (definitive surgery, adjuvant chemo-, and/or radio-therapy, if administered), BMI ≥25 kg/m2, ability to walk at least 400 meters at any pace, ECOG PS 0-1, not participating in another weight loss, dietary or PA intervention clinical trial.

Intervention and Control arms: The intervention and health education program are adapted from the BWEL: Breast Cancer WEight Loss study (ClinicalTrials.gov NCT02750826; PI Ligibel JA). The behavior change program is based on the Social Cognitive Theory. Patients in the intervention arm are paired with an individual lifestyle coach, who delivers the intervention through 24 semi-structured telephone calls of 30-60 minutes, supplemented by a detailed participant workbook and scheduled as follows: 1) intensive phase (weeks 1-12), 12 weekly calls; 2) consolidation phase (weeks 13-24), 6 bi-weekly calls; 3) maintenance phase (weeks 25-52), 1 monthly call. Coaches were hired and trained specifically for MEDEA, they are located at a centralized call center and receive support from coordinating nutrition, PA, and behavioral experts. Regular meetings with study team and investigators assure standardized delivery of the intervention and troubleshooting. Intervention goals include weight loss ≥10% of baseline weight, caloric restriction of 500-1000 Kcal/day, increased PA to 150 minutes/week in the initial phase and 225-300 minutes/week in the maintenance phase. Toolbox solutions are offered to tailor the intervention and meet the needs of specific ethnic, socioeconomic or other patient populations with difficulties in achieving intervention goals. All participants in both arms receive a health education program focusing on healthy living.

Accrual: MEDEA will enroll 220 patients overall. Recruitment started in June 2020.

Statistical considerations: The primary analysis of MEDEA will compare the primary endpoint of CRF scores at the 12-month post-randomization time point between arms. The study has 90.0% power at two-sided α=0.05 to detect a standardized effect size of 0.40 (sample size inflated for drop outs). For interpreting the clinical significance of effects, 0.2, 0.5 and 0.8 standard deviation effects will be considered as small, moderate, and large (Cohen, 1988). All other measures, time points and analyses will be considered secondary or exploratory.

Citation Format: Antonio Di Meglio, Elise Martin, Stefan Michiels, Cecile Charles, Tracy E. Crane, Aude Barbier, Bruno Raynard, Anthony Mangin, Olivier Tredan, Paul H. Cottu, Laurence Vanlemmens, Carine Segura-Djezzar, Anne Lesur, Barbara Pistilli, Florence Joly, Thomas Ginsbourger, Bernadette Coquet, Guillemette Jacob, Aude Sirven, Julia Bonastre, Jennifer A. Ligibel, Ines Vaz-Luis. MEDEA: A randomized trial of weight loss to reduce cancer-related fatigue (CRF) among overweight and obese breast cancer (BC) patients [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 OT-38-01.

Changes in weight, physical and psychosocial patient-reported outcomes among obese women receiving treatment for early-stage breast cancer: A nationwide clinical study

BACKGROUND

Evidence on how weight loss correlates to health-related quality-of-life (HRQOL) among obese breast cancer (BC) patients is limited. We aimed to evaluate associations between weight changes and HRQOL.

METHODS

We included 993 obese women with stage I-II-III BC from CANTO, a multicenter, prospective cohort collecting longitudinal, objectively-assessed anthropometric measures and HRQOL data (NCT01993498). Associations between weight changes (±5% between diagnosis and post-treatment [shortly after completion of surgery, adjuvant chemo- or radiation-therapy]) and patient-reported HRQOL (EORTC QLQ-C30/B23) were comprehensively evaluated. Changes in HRQOL and odds of severely impaired HRQOL were assessed using multivariable generalized estimating equations and logistic regression, respectively.

RESULTS

14.1% women gained weight, 67.3% remained stable and 18.6% lost weight. Significant decreases in functional status and exacerbation of symptoms were observed overall post-treatment. Compared to gaining weight or remaining stable, obese women who lost weight experienced less of a decline in HRQOL, reporting better physical function (mean change [95%CI] for gain, stability and loss: -12.9 [-16.5,-9.3], -6.9 [-8.2,-5.5] and -6.2 [-8.7,-3.7]; pinteraction[weight-change-by-time] = 0.006), less dyspnea (+18.9 [+12.3,+25.6], +9.2 [+6.5,+11.9] and +3.2 [-1.0,+7.3]; pinteraction = 0.0003), and fewer breast symptoms (+22.1 [+16.8,+27.3], +18.0 [+15.7,+20.3] and +13.4 [+9.0,+17.2]; pinteraction = 0.044). Weight loss was also significantly associated with reduced odds of severe pain compared with weight gain (OR [95%CI] = 0.51 [0.31-0.86], p = 0.011) or stability (OR [95%CI] = 0.62 [0.41-0.95], p = 0.029). No associations between weight loss and worsening of other physical or psychosocial parameters were found.

CONCLUSIONS

This large contemporary study suggests that weight loss among obese BC patients during early survivorship was associated with better patient-reported outcomes, without evidence of worsened functionality or symptomatology in any domain of HRQOL.

Serum Detection of Nonadherence to Adjuvant Tamoxifen and Breast Cancer Recurrence Risk

PURPOSE

Nonadherence to long-term treatments is often under-recognized by physicians and there is no gold standard for its assessment. In breast cancer, nonadherence to tamoxifen therapy after surgery constitutes a major obstacle to optimal outcomes. We sought to evaluate the rate of biochemical nonadherence to adjuvant tamoxifen using serum assessment and to examine its effects on short-term, distant disease-free survival (DDFS).

PATIENTS AND METHODS

We studied 1,177 premenopausal women enrolled in a large prospective study (CANTO/NCT01993498). Definition of biochemical nonadherence was based on a tamoxifen serum level < 60 ng/mL, assessed 1 year after prescription. Self-reported nonadherence to tamoxifen therapy was collected at the same time through semistructured interviews. Survival analyses were conducted using an inverse probability weighted Cox proportional hazards model, using a propensity score based on age, staging, surgery, chemotherapy, and center size.

RESULTS

Serum assessment of tamoxifen identified 16.0% of patients (n = 188) below the set adherence threshold. Patient-reported rate of nonadherence was lower (12.3%). Of 188 patients who did not adhere to the tamoxifen prescription, 55% self-reported adherence to tamoxifen. After a median follow-up of 24.2 months since tamoxifen serum assessment, patients who were biochemically nonadherent had significantly shorter DDFS (for distant recurrence or death, adjusted hazard ratio, 2.31; 95% CI, 1.05 to 5.06; P = .036), with 89.5% of patients alive without distant recurrence at 3 years in the nonadherent cohort versus 95.4% in the adherent cohort.

CONCLUSION

Therapeutic drug monitoring may be a useful method to promptly identify patients who do not take adjuvant tamoxifen as prescribed and are at risk for poorer outcomes. Targeted interventions facilitating patient adherence are needed and have the potential to improve short-term breast cancer outcomes.

Updated results from the phase IIIb complement-1 study of ribociclib (RIB) plus letrozole (LET) in the treatment of HR+, HER2-advanced breast cancer (ABC)

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Background: Real-world evidence is important as it complements data from randomized controlled trialse report updated results from CompLEEment-1, a Phase IIIb trial evaluating RIB+LET in an expanded population, the largest CDK4/6i trial in ABC to date. Methods: Patients (pts) with HR+, HER2– ABC, ≤ 1 line of prior CT and no prior ET for ABC received RIB+LET. Study design has been reported previously (De Laurentiis, et al. ASCO 2019). Primary endpoints were safety and tolerability. Results: 3,246 pts received ≥ 1 dose of study treatment. Median duration of follow-up was 25.4 months (mos) (15 additional mos since interim analysis [De Laurentiis, et al. ABC5 2019]). Median treatment exposure was 17.8 mos. Baseline characteristics indicated a diverse population, including men (1.2%), premenopausal women (22.2%), and pts aged ≥ 70 years (19.5%); 112 (3.5%) pts had an ECOG PS of 2, 194 (6.0%) pts received prior CT for ABC, and 51 (1.6%) pts had stable CNS lesions. The most common adverse events (AEs) were neutropenia (61.1%), nausea (35.9%), and fatigue (23.4%). Grade 3/4 hematologic abnormalities ( > 5.0 %) were decreased neutrophils (54.8%), leukocytes (25.9%), and lymphocytes (12.6%). Grade 3/4 biochemical abnormalities ( > 5.0 %) were increased ALT (9.1%) and AST (6.7%). An increase of > 60 ms in QTcF interval from baseline occurred in 189 (5.9%) pts, while post-baseline QTcF of > 480 to ≤ 500 ms and > 500 ms occurred in 59 (1.8%) and 42 (1.3%) pts, respectively. Treatment-related AEs led to treatment discontinuation in 418 (12.9%) pts. Of 74 (2.3%) on treatment deaths, 38 (1.2%) were due to breast cancer. Median time to progression was 27.1 mos (95% CI, 25.7-NE), overall response rate was 43.6% (95% CI, 41.5-45.8%), and clinical benefit rate was 69.1% (95% CI, 67.1-71.1%) for pts with measurable disease at baseline. Conclusions: This analysis confirms the safety and efficacy of RIB+LET in a large, diverse cohort of pts with HR+, HER2– ABC (with no previous ET for ABC), closely resembling real-world clinical practice. Safety and efficacy data were consistent with those observed in the MONALEESA trials, supporting the use of RIB+LET in the first-line setting. NCT02941926. Clinical trial information: NCT02941926 .

Tolerance of concurrent CDK inhibitor and radiation therapy in metastatic breast cancer patients

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Background: Palbociclib, a small-molecule inhibitor of cyclin-dependent kinases (CDK4 and CDK6), combined with letrozole increases progression-free survival among patients with previously untreated ER-positive, HER2 negative advanced breast cancer. The purpose of our study was to retrospectively evaluate the tolerance of the concomitant association of Palbociclib and radiation therapy (RT) at Curie Institute. Methods: Between April 2017 and August 2019, 30 women with ER-positive, HER2 negative metastatic breast cancer received locoregional (LR) and/or symptomatic irradiation at a metastatic site concurrently with Palbociclib at a daily dose of 125 mg, from d1 to d21 every 28 days. Palbociclib was always associated with endocrine therapy: letrozole (with or without an LHRH analogue) or fulvestrant. Thirty-five sites were irradiated: nine patients received post-operative locoregional RT, including the chest wall or breast and lymph node areas, and 26 sites of metastases were irradiated: 17 at the spine, 7 peripheral skeletal lesions, 1 brain lesion and 1 choroidal lesion. The dose prescribed for locoregional mammary radiotherapy was 50 Gy in 25 fractions and varied for the treatment of metastatic sites: 20 Gy in 5 fractions (n = 13), 30 Gy in 10 fractions (n = 10) and 8 Gy in 1 fraction (n = 2). The brain metastasis was stereotactically treated (1 fraction of 18 Gy). The primary endpoint was toxicity scored according to the common terminology criteria for NCI adverse events, version v5.0. Results: Mean number of days of Palbociclib during RT was 8.8 days (range, 1 to 24 days). The most common acute toxicities were dermatitis (12/35, including 2 grade 2) and neutropenia (12/35, including 9 grade 2). Palbociclib had to be stopped during the RT of two patients (2/30): one patient treated locoregionally (bilateral breast and lymph nodes irradiation) developed a grade 3 dermatitis and febrile neutropenia, another treated locoregionally developed grade 2 dysphagia. After a median follow-up since the end of RT of 17 months (6 – 31 months, SD 8), none of the patients have so far exhibited late toxicity. Conclusions: Concomitant administration of palbociclib with RT was reasonably well tolerated in our series of 30 patients. Given this experience, palbociclib should not be discontinued during radiation therapy. Nevertheless, our findings should be confirmed in prospective registration studies collecting larger number of patients.

Questions prompt lists used by palliative care teams help trigger discussions on prognosis and end-of-life issues with advanced cancer patients

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Background: Accuracy of prognosis perception is a key element to allow advanced cancer patients to make informed decisions and to reflect on their end-of-life priorities. This study aims to explore whether a question prompt list can promote discussions on prognosis and end-of-life issues during palliative care consultations for advanced cancer patients. Methods: In this multicentric randomised study, patients assigned in the interventional arm receive a question prompt list during the first palliative care consultation (T1) after referral by oncologists. The primary endpoint is the number of questions asked by patients during the second palliative care consultation (T2) one month later. Secondary objectives are anxiety and depression, quality-of-life, satisfaction with care, coping assessed at baseline (T1) and at two months (T3). Palliative care teams from 3 french comprehensive cancer centers participate in the study. Main inclusion criteria were adult patients with metastatic non-haematological cancer referred to the palliative care team and with an estimated life expectancy less than one year. Results: Patients (n = 71) in the QPL arm asked more questions (mean 21.8 versus 18.2, p-value = 0.03) during the palliative care consultations compared to patients in the control arm (n = 71). These questions addressed palliative care (mean 5.6 versus 3.7, p-value = 0.012) and end-of-life issues (mean 2.2 versus 1, p = 0.018) more frequently than in the control arm. At two months, compared to baseline, there was no change in anxio-depressive symptoms or quality of life. Conclusions: QPL favours discussion on prognosis and end-of-life care during the palliative care consultations for advanced cancer patients. Clinical trial information: NCT02854293 .

Assessment of the efficacy of successive endocrine therapies in hormone receptor-positive and HER2-negative metastatic breast cancer: a real-life multicentre national study

BACKGROUND

For luminal metastatic breast cancer (MBC), endocrine therapy (ET) is the recommended initial treatment before chemotherapy. Our objective was to evaluate the efficacy of multiple ET lines in a real-life study.

METHODS

The Breast Cancer Epidemiological Strategy and Medical Economics (ESME) project analysed data from all patients with systemic treatment for MBC initiated between 2008 and 2014 in one of the 18 French Comprehensive Cancer Centres. The primary end-point was the successive progression-free survival (PFS) evaluation.

RESULTS

The ESME research programme included 9921 patients with hormone receptor-positive (HR+)/human epidermal growth factor receptor 2 (HER2) negative (HER2-) MBC. Before any chemotherapy, 4195 (43.4%), 1252 (29.8%) and 279 (6.6%) patients received one, two or three ET ± targeted therapy, respectively. The median PFS for first-, second- and third-line ET ± targeted therapy was 11.5 (95% confidence interval [CI], 10.8-12.1), 5.8 (95% CI, 5.3-6.1) and 5.5 (95% CI, 4.6-6.3) months, respectively. In a multivariate analysis, time from diagnosis to metastatic recurrence (P < 0.0001), presence of symptoms at metastatic relapse (P = 0.01), number of metastatic sites (P = 0.0003) and their localisation (P < 0.0001) were prognostic factors for PFS1. Duration of previous PFS was the only prognostic factor for subsequent PFS (10% threshold). Ten percent of the patients showed long-term response to ET, with a total treatment duration before chemotherapy ≥43.6 months.

CONCLUSIONS

Median PFS in our HR+/HER2- real-life cohort is similar to median first-line PFS reported in clinical trials, regardless of ET used as second- and third-line treatment. Despite the international consensus on early initiation of ET, the latter is not prescribed in most of the cases. Patients with a low tumour burden may achieve prolonged response on ET.

High temporal variability of clinical side effects with and without adjuvant chemotherapy in 4,684 early breast cancer patients in the CANTO trial

11566

Background: CANTO (CANcer TOxicities - NCT01993498) is a French multicenter prospective longitudinal study dedicated to the quantification and characterization of side effects after treatment for patients with stage I-III breast cancer, and to the development of predictors of toxicities. Methods: The CANTO study has included > 12,000 patients, assessed at diagnosis, and 3-6 months (T0), 15 months (T12), and year 3 and 5 after treatment completion. In the current report, we focus on key toxicities at T0 and T12 according to chemotherapy (CT) administration. For each side effect, 4 populations were defined according to its occurrence at T0 and/or T12 (no/no, no/yes, yes/no, yes/yes). Results: We analyzed 4684 patients with T0 and T12 consolidated data. Median age at diagnosis was 57y (22-89). Patients (pts) had HR+/HER2-, HER2+ or triple negative tumors in 78.9%, 12.4% and 8.7% of cases, respectively. Overall, 2516 pts (53.7%) received CT. Most CT pts (81%) received a sequential anthracyclines– taxanes schedule. As an example, a high proportion of patients presented neurological symptoms including cognitive symptoms, sensory or motor neuropathy, paresthesia, headache, etc (all grades) at either T0 or T12. Overall, CT was strongly associated with neurotoxicity at all times (OR = 2.27, p < 0.0001). However, proportions of patients with neurological side effects changed between T0 and T12. The table shows the proportions of the 4 categories of pts in the CT and no CT groups. Furthermore, at T12, neurological symptoms remained more frequent in the CT group, whether pts had symptoms at T0 (CT vs no CT, 81% vs 77%, p = 0.007) or not (CT vs no CT, 41% vs 36%, p = 0.03). Similar temporal trends were observed (with specific percentages for each considered side effect) for detailed neurological toxicities, pain and joint/bone toxicity (stratified on endocrine therapy), gastro-intestinal, pulmonary and cardiac toxicities. Conclusions: Overall, symptoms burden is extremely high at T0 and T12 after treatment, and much higher in pts receiving CT. A high temporal variability was observed in all subsets, including a clinically meaningful delayed onset of e.g. neurological side effects. Clinical trial information: NCT01993498. [Table: see text]

Interim results from the full population of the phase 3b CompLEEment-1 study of ribociclib (RIBO) plus letrozole (LET) in the treatment of HR+/HER2– advanced breast cancer (ABC)

1041

Background: RIBO, an oral, selective inhibitor of CDK4/6 (CDK4/6i), is approved for use in combination with endocrine therapy (ET) in women with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2–) ABC in multiple countries worldwide. Here we report interim safety and efficacy results from CompLEEment-1, a phase 3b trial evaluating RIBO+LET in an expanded patient (pt) population and the largest CDK4/6i trial in ABC to date. Methods: Pts with HR+, HER2– ABC, ≤1 line of prior chemotherapy (CT), and no prior ET for ABC received RIBO+LET. Treatment regimens and study endpoints have been reported previously (De Laurentiis, et al. ASCO 2018. Poster 1056). Results: Overall, 3,246 pts, who received ≥1 dose of study treatment, were evaluated (cut-off date, August 8, 2018). Median duration of RIBO exposure was 8.1 months (min, 0.0; max, 22.4). Demographic and baseline characteristics indicated a diverse population including men (1.2%), premenopausal women (22.2%), and patients aged ≥70 years (19.5%). Pts were well represented in terms of age, race, and disease history; 5.9% of pts received prior CT for ABC. The only non-hematologic any-cause grade ≥3 AEs ≥5% were increased alanine (7.3%) and aspartate (5.3%) aminotransferase. Treatment-related AEs (any grade) led to discontinuation in 11.4% of pts. Of the 51 (1.6%) on-treatment deaths, 26 were due to study indication and 25 to other reasons. The median time to progression was not estimable (NE) (95% confidence interval [CI], 17.1-NE). Overall response rate was 20.5% (95% CI, 19.1%-21.9%) and clinical benefit rate was 66.1% (95% CI, 64.4%-67.7%). Consistent mean change from baseline in Functional Assessment of Cancer Therapy – Breast Cancer questionnaire scores indicated that pts maintained their quality of life throughout treatment. Conclusions: This interim analysis demonstrates the safety, tolerability, and efficacy of RIBO+LET in a large, diverse cohort of pts with HR+, HER2– ABC who had not previously received ET for ABC. Safety results were consistent with those observed in RIBO pivotal studies and no new safety signals were observed. Clinical trial information: NCT02941926.

Pooled analysis of onapristone extended release (ONA ER) in metastatic cancer patients (pts): A review of liver safety

e14647

Background: ONA, a type I progesterone receptor (PR) antagonist, prevents PR activation by disrupting PR dimerization and DNA binding, and inhibits tumor progression. ONA (immediate release) has efficacy comparable to other endocrine therapies in pts with metastatic breast cancer (BC). The only notable toxicity was transient elevation in liver chemistries in some pts. In 2 clinical trials, ONA ER was given to 88 cancer pts who underwent frequent liver chemistry monitoring. Methods: We pooled and reviewed all liver safety data from 2 trials. A hepatologist (PBW) reviewed all pts with either a hepatobiliary SOC AE or who experienced an elevation > ULN of any liver-related laboratory test. Results: Of 88 pts who received ONA ER for a median 8 weeks (3-51), 59% were female, median age 68 (36-89), 99% Caucasian, 28% had liver metastases (mets), 48% bone mets and 17% also took abiraterone (ABI), which has liver toxicity. 54 pts (61%) experienced any ONA ER-related AE. More AEs were seen in ABI pts (67%), those with liver mets (72%) and BC (76%).. In terms of liver-related TEAEs, overall 10% of pts had ALT and 13% AST elevations, while 20% pts with liver mets had raised ALT/AST and 29% of BC pts. Overall 15% pts had G3 TEAEs, compared to 28% pts with liver mets, mostly due to increased GGT (24%), which has unclear clinical impact. There were no discontinuations for LFT elevations. A relationship between the liver events and ONA ER was judged to be unlikely in each subject, except one. This event was detected at day 29 of treatment and consisted of a marked rise in serum GGT and alkaline phosphatase with only a moderate rise in serum ALT (peak – 262). These abnormalities improved quickly after stopping ONA but recurred on reintroduction: these events are not serious by international criteria and the pt was able to continue ONA at a lower dose for 40 weeks without recurrence Conclusions: The safety experience for ONA ER has been reassuring but must continue to be characterized. For new ONA ER studies, weekly liver chemistry monitoring is planned for the first 4 weeks with Q2W monitoring thereafter. The occasional G3 elevations in serum AST, ALT or bilirubin will prompt interruption, but re-starting treatment at a lower dose should be possible for most pts. Clinical trial information: NCT02052128 and NCT02049190.

Return to work after breast cancer: Comprehensive longitudinal analyses of its determinants

11564

Background: The interplay between breast cancer (BC) late effects, psychosocial and work-related factors in return to work (RTW) is not well understood. Previous reports were retrospective and did not combine all these features. Methods: We used data of a French prospective cohort study (CANTO, NCT01993498) of stage I-III BC patients (pts) including detailed clinical data of 1,874 pts working at diagnosis (dx) and ≥5 years younger than legal retirement age. The outcome was non-RTW 2 years after dx. Multivariable regressions were conducted to identify correlates of non-RTW. First, we examined the independent effect of treatments, toxicities (Common Toxicity Criteria Adverse Events), and patient reported outcomes (EORTC BR23 and FA12; Hospital Anxiety and Depression Scale) collected shortly after end of primary treatment. Then, in a restricted sample of 1,003 pts with working conditions (WC) information available, we fitted models to account for detailed pre-dx WC including type of contract, working hours, strenuous postures, supportive environment, degree of autonomy and perception of work. All models were adjusted for age, stage, marital status, socioeconomic status and comorbidities. Results: Two years after dx, 21% of pts did not work. Adjusted odds of non-RTW were increased among pts treated with combinations of chemotherapy (CT) and trastuzumab (TR) (e.g. OR of CT-TR = 2.20 [95% CI 1.24-3.88] and OR of CT-TR-hormonotherapy (HT) = 1.72 [1.13-2.63] vs. treated only with CT-HT), who had severe arm morbidity (OR = 1.73 [1.27-2.36] vs. no), severe emotional fatigue (OR = 1.55 [1.03-2.32] vs. no), anxiety (OR = 1.51 [1.02-2.23] vs. no), or depression (OR = 2.23 [1.27-3.94] vs no). In addition, we also found that the odds of non-RTW were increased among pts who had shift working hours (OR = 2.23 [1.32-3.76] vs. no), who did not work in a supportive environment before dx (OR = 2.24 [1.44-3.50] vs. supportive) and who perceived their job as boring (OR = 3.57 [1.71-7.46] vs. not boring). Conclusions: More than 1/5 of pts did not RTW 2 years after dx, with treatment (trastuzumab), clinical, psychological and work-related factors being associated with job reintegration. Multidisciplinary strategies are needed to support BC survivors.

Prediction of treatment (tx)-induced fatigue in breast cancer (BC) patients (pts) using machine learning on genome-wide association (GWAS) data in the prospective CANTO cohort

11515

Background: Many BC survivors report fatigue. The relevant genomic correlates of fatigue after BC are not well understood. We applied a previously validated machine learning methodology (Oh 2017) to GWAS data to identify biological correlates of fatigue induced after tx. Methods: We analyzed 3825 BC pts with GWAS data (Illumina InfiniumExome24 v 1.1) from the CANTO study (NCT01993498). The outcome of this study was post-tx fatigue 1 year after the end of primary chemotherapy/radiotherapy/surgery using the EORTC C30 fatigue subscale (overall fatigue) and the EORTC FA 12 fatigue domains (physical/emotional/cognitive). For each domain, we limited the study group to those with zero baseline fatigue and defined severe fatigue change as score increase above the third quartile. We tested univariate correlations between severe fatigue in each domain and 496539 SNPs as well as relevant clinical variables. The machine learning prediction model based on preconditioning random forest regression (PRFR) (Oh et al., 2017), was then built using the SNPs with ancestry adjusted univariate p-value < 0.001 and clinical variables with Bonferroni adjusted p-value < 0.05. The model was validated in a holdout subset of the cohort. Gene set enrichment analysis (GSEA) was performed using MetaCore to identify key biological correlates relevant to tx-induced fatigue. Results: Distinct results were found by fatigue domain (table). GSEA showed that the cognitive fatigue model SNPs included biomarkers for cognitive disorders (p = 1.6 x 10-12) and glutamatergic synaptic transmission (p = 1.6 x 10-8). Conclusions: A SNP based model had differential performance by fatigue domain, with a potential genetic role on risk and biology for tx induced cognitive fatigue. Further research to explore biomarkers of tx induced fatigue are needed. [Table: see text]

mTORC1 activation assessed in metastatic sample to predict outcome in patients with metastatic breast cancer treated with everolimus-exemestan: Results from the SAFIRTOR study

1024

Background: Using samples from TAMRAD study (Treilleux, Ann Oncol, 2015), we previously reported that p4EBP1, a downstream protein of mTOR, was associated with higher benefit to everolimus (eve). SAFIRTOR study was designed to validate clinical utility of this biomarker. Methods: Patients (pts) with ER+, HER2 negative, AI resistant MBC were prospectively included (NCT02444390). All pts had a biopsy of a metastatic site and were then treated with standard eve + exemestane (exe) combination. The primary end point was to validate that p4EBP1 expression is associated with longer PFS in patients treated with eve. 120 evaluable pts were needed for the pre planed statistical analysis. All samples were collected and processed in a standardized procedure in order to allow phophoproteins IHC staining. In addition to p4EBP1, we explored prognostic value of pS6K, pAkt, PTEN and LKB1, together with genomic alterations assessed by NGS and CGH arrays. Results: 150 pts were included, 30 pts had no adequate sample, and further 13 had missing clinical data, 107 were evaluable for primary objective. Median age was 62, they had previously progressed on AI treatment, either in the adjuvant (22 pts) or the metastatic setting (83 pts). 20 were considered as primary hormone resistant, 87 as secondary resistant. The median Allread score for p4EBP1 was 5.5 (range: 0-6.5). Analysis of the primary endpoint showed that p4EBP1 staining above the median is associated with a longer PFS on eve+exe. (median PFS: 9.3 months, 95CI 6.3-13.1 for high p4EBP1 versus 5.8 months, 95CI 3.7-7.8 for low p4EBP1, p = 0.02). Prognostic value of high pEBP1 remained significant when assessed in a multivariate analysis along classical clinico-biological prognostic factors for MBC (HR 0.57, 95%CI 0.38-0.88, p = 0.01). In this AI resistant population, the tumor of 42 (46%), 33 (35%) and 5 (5.3%) pts carried an activating mutation for ESR1, PIK3CA and AKT1, respectively. None of these mutational statuses were correlated to outcome. Conclusions: This prospective study validates p4EBP1 expression analysis to select patients most likely to benefit from everolimus + exemestane. Clinical trial information: NCT02444390.

Abstract P4-15-02: TILs variations, proliferative response and PEPI scores in patients with luminal breast cancer receiving neoadjuvant letrozole-palbociclib or chemotherapy: An extended analysis of the NEOPAL trial

Background

The role of chemotherapy in early luminal breast cancer remains challenged. The NEOPAL trial (NCT 02400567; Cottu et al, ESMO 2017 LBA09) compared sequential chemotherapy (CT) and letrozole-palbociclib (LP) as neoadjuvant treatment in PAM50 defined high-risk luminal breast cancer patients, showing that LP might be as efficient as CT with regard to breast conserving surgery and pathological response. We report here extended exploratory pathological results, focusing on tumor infiltrating lymphocytes (TILs), proliferative response and preoperative endocrine prognostic index (PEPI) scores.

Material and Methods

Tumor blocks from baseline biopsy and surgical specimens were available for centralized review from the 106 randomized patients (53 in each arm). TILs quantification, KI67 staining and counting, and ER quantification were performed according to standard methods. Residual proliferative cancer burden (RPCB) and PEPI scores were computed according to published algorithms. Wilcoxon rank sum test and Mann Whitney test were used to compare paired and unpaired data. The chi-square and Fisher exact tests were used for categorical variables.

Results

Overall, median TILs count did not differ between LP and CT patients, both at baseline (p=0.37) and at the end of treatment (p=0.42). Median TILs count climbed from 5% (0-60) to 10% (1-60) in the LP arm (p=0.0026) and from 2% (0-30) to 10% (0-60) in the CT arm (p=0.0023). Median Ki67 dropped sharply in both arms, from 30% (1-80) to 1% (0-30) in the LP arm (p=1.10e-8) and from 30% (2-80) to 5% (0-30) in the CT arm (p=3.10e-9). Decrease in the Ki67 geometric mean was as sharp. Of note, while baseline Ki67 was similar in both arms (p=0.315), decrease in the LP arm was significantly more profound than in the CT arm (p=0.00075). Pathological response according to RPCB were as follows, in the LP and CT arm, respectively: class 0: 9.6%/10.2%; class I: 84.6%/73.5%; class II: 5.8%/16.3%. The relapse free survival PEPI scores were as follow in the LP and CT arm, respectively: class I: 13.5%/16.3%; class II: 59.6%/46.9%; class III: 28.9%/36.8% (p=0.504). Breast cancer specific survival PEPI scores were as follow in the LP and CT arm, respectively: class I: 18.9%/8.2%; class II: 54.7%/40.8%; class III: 26.4%/51%. These results were significantly better in the LP arm (p=0.027). There was no correlation between final TILs quantification and the RPCB or PEPI scores.

Conclusions

In this prospective multicenter study with centralized pathological review, neoadjuvant letrozole-palbociclib combination generates impressive proliferative and endocrine specific response features. It compared well with chemotherapy. The LP combination also significantly increased lymphocytic infiltration. Its clinical significance and utility remain to be elucidated, but it potentially adds new prognostic and theranostic information.

Citation Format: Vincent-Salomon A, Mathieu M-C, Bataillon G, Arnould L, Verrièle V, Ghnassia J-P, Haudebourg J, Penault-Llorca F, Lefebvre C, Maran-Gonzalez A, Guinebretière J-M, Duprez R, Berghian A, Blanc-Fournier C, Calès V, Galant C, Delrée P, Lemonnier J, Delaloge S, Cottu PH. TILs variations, proliferative response and PEPI scores in patients with luminal breast cancer receiving neoadjuvant letrozole-palbociclib or chemotherapy: An extended analysis of the NEOPAL trial [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-15-02.

Phase I study of onapristone, a type I antiprogestin, in female patients with previously treated recurrent or metastatic progesterone receptor-expressing cancers

INTRODUCTION

Onapristone is a type I progesterone receptor (PR) antagonist, which prevents PR- mediated DNA transcription. Onapristone is active in multiple preclinical models and two prior studies demonstrated promising activity in patients with breast cancer. We conducted a study of extended release (ER) Onapristone to determine a recommended dose and explore the role of transcriptionally-activated PR (APR), detected as an aggregated subnuclear distribution pattern, as a predictive biomarker.

METHODS

An open-label, multicenter, randomized, parallel-group, phase 1 study (target n = 60; NCT02052128) included female patients ≥18 years with PRpos tumors. APR analysis was performed on archival tumor tissue. Patients were randomized to five cohorts of extended release (ER) onapristone tablets 10, 20, 30, 40 or 50 mg BID, or immediate release 100 mg QD until progressive disease or intolerability. Primary endpoint was to identify the recommended phase 2 dose. Secondary endpoints included safety, clinical benefit and pharmacokinetics.

RESULTS

The phase 1 dose escalation component of the study is complete (n = 52). Tumor diagnosis included: endometrial carcinoma 12; breast cancer 20; ovarian cancer 13; other 7. Median age was 64 (36-84). No dose limiting toxicity was observed with reported liver function test elevation related only to liver metastases. The RP2D was 50 mg ER BID. Median therapy duration was 8 weeks (range 2-44), and 9 patients had clinical benefit ≥24 weeks, including 2 patients with APRpos endometrial carcinoma.

CONCLUSION

Clinical benefit with excellent tolerance was seen in heavily pretreated patients with endometrial, ovarian and breast cancer. The data support the development of Onapristone in endometrial endometrioid cancer. Onapristone should also be evaluated in ovarian and breast cancers along with APR immunohistochemistry validation.

Abstract P6-12-18: CANTOCHEM: Analysis of chemotherapy practice and early side effects in the 6090 first patients from the prospective CANTO cohort

Background

There is no large prospective trial assessing mid-term adverse effects of adjuvant chemotherapy. In order to address this question, we developed CANTO (CANcer TOxicities - NCT01993498 - http://etudecanto.org/), a prospective trial dedicated to the quantification of side effects after treatment for patients with early breast cancer and to develop predictors of such toxicities. The aim of this presentation is to assess chemotherapy (CT) practice and to report toxicities that persist 3-6 months after CT.

Methods

CANTO is a prospective study enrolling newly diagnosed invasive cT0-cT3, cN0-3, M0 breast cancer patients (pts) of 26 French comprehensive cancer centers. The study has included 10 500 patients at the time of submission. Pts are assessed at diagnosis, 3-6, 12, 36, 48 and 60 months after treatment completion. CANTO collects &gt;100 items related to toxicities. In the current study, we focus on the first set of data available from the trial (1st database lock, n=6090). We here assess CT practice and toxicities at 3 months.

Results

Information about (neo)adjuvant CT (NACT/ACT) is available in 5805 pts (96%). Median age at diagnosis was 57y (22-93). Pts had HR+/HER2-, HER2+ or triple negative (TN) tumors in 74%, 15% and 11% of cases. Ki67 was assessed in 70%, and genomic tests in 1% of pts, respectively.

Overall, 3074 pts (53%) received CT, either adjuvant (ACT: 76%) or neoadjuvant (NACT: 24%). ACT/NACT pts (84%) received a sequential anthracyclines–taxanes based 6 courses CT schedule. CT was administered in 44.7%, 87.2% and 92.3% of HR+/HER2+/TN tumors, respectively. ACT was administered in 73.2% of pT2+ pts (vs 36.0% in pT0-1 – p&lt;.001)) and in 74.7% in pN1+pts (vs 36.7% in pN0 – p&lt;.001)). After NACT, pts had yPT0 (32.3%) and/or ypN0 (64.6%) for an overall 28.9% pCR rate.

We focus here on clinically most relevant patient reported symptoms at 3 m (any grade).

side effects at 3m no CT (%)CT (%)p valuePain76.682.1&lt;.001Neurological symptom4768.7&lt;.001GI symptom34.342.1&lt;.001CV sympton8.110.20.011

Pain complaint was recorded in 3596 pts (97.2% of pts with available data), with a median value of 4 on the VAS (range 1-10). In ACT/NACT pts, muscle and joint pain were predominant. Neurological symptoms were seen in 3024 pts (59%), the most frequent pertaining to cognitive disorder (attention trouble, CT: 61.2% vs noCT: 56% - p=.06) and peripheral neuropathy (overall 31%). Paresthesias and sensory neuropathy were much more frequent in CT vs noCT pts: respectively 37.3% vs 20.3% and 25.7% vs 12.8% (both p&lt;.001). Of note, pts receiving paclitaxel had more peripheral neuropathy (92.3% vs 69% in docetaxel pts – p=.07). Diarrhea was the most frequent GI symptom post CT: 44.5% vs 33.2%, p&lt; 0.001. CV symptoms (NOS) were slightly more frequent after CT.

Conclusions

In this real life, prospective cohort, CT is frequently prescribed and appears in good compliance with current guidelines. Overall, symptoms burden at treatment completion is strikingly high, and much higher in pts receiving CT. A special attention should be given to pain and neurological symptoms. Dedicated questionnaires and sub-studies will explore in depth these side effects. Extended analyses of CT practice and toxicities will be presented.

Citation Format: Cottu PH, Amar Y, Pistilli B, Bonsang-Kitzis H, Lesur A, Lerebours F, Vanlemmens L, Tredan O, Levy C, Jouannaud C, Fournier M, Soulie P, Rigal O, Giacchetti S, Arnaud A, Arsene O, Savignoni A, Mesleard C, Andre F, Arveux P. CANTOCHEM: Analysis of chemotherapy practice and early side effects in the 6090 first patients from the prospective CANTO cohort [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P6-12-18.

Abstract P3-13-02: Withdrawn

This abstract was withdrawn by the authors.

UNICANCER: Prospective cohort study of treatment related chronic toxicities in patients with localized breast cancer (CANTO)

TPS10125

Background: Corresponding with improved survival among breast cancer patients an awareness of the long term effects of cancer treatments has increased. There is now a call for better coordination of care and management of these patients to focus on their survivorship. This study will identify factors associated with the development and persistence of long term toxicities in patients treated for Stage I-III breast cancer. In addition, it will characterize their incidence as well as, psychological, social and economic impacts. Methods: This is a prospective cohort study enrolling newly diagnosed invasive cT0-cT3, cN0-3, M0 breast cancer patients of 26 French comprehensive cancer centers. All patients will be followed for a minimum of 5 years. Patients will be assessed at diagnosis, 3-6 (M0), 12 (M12), 36 (M36), 48 (M48), 60 (M60), months after treatment completion. Treatment completion is defined as completion of primary surgery, chemotherapy or radiotherapy, whichever comes last. Adjuvant trastuzumab, endocrine therapy or participation in clinical trials can be ongoing. CANTO collects an extensive list of clinical, treatment, and toxicity data including validated patient reported outcomes questionnaires ( Hospital Anxiety and Depression scale [HADS], Scheier et Carver’s Questionnaire, Life Orientation Test-Revised [LOT-R], Beck Depression Inventory [BDI-SF], European Organization for Research and Treatment-QOL questionnaire for breast cancer [EORTC QLQC30-BR23], EORTC-FA13, 12 Item Short Form Survey [SF12], Global physical activity questionnaire [GPAQ]6, impact of cancer questionnaire [IOCv2], economic and social questionnaires). Blood collection is available for all patients at diagnosis, M0, M12, M36 and M60. Genotyping will be performed in all samples. Biologic substudies are ongoing (e.g, microbiotic and cognitive substudy). CANTO aggregates a multidisciplinary team of French investigators and created a dedicated national network. Enrolment started in 2012 and by December 2016, 10030 patients were already enrolled, with a goal of 12.000 patients. Clinical trial information: NCT01993498.

Pharmacogenetics revisits bevacizumab in breast cancer patients: An ancillary analysis of the UCBG trial COMET—A French multicentric prospective study from R&D UNICANCER

1079

Background: Bevacizumab (Beva) is no longer unanimously recommended in the management of breast cancer (BC). Given the absence of faithful predictors of Beva treatment outcome, we made the hypothesis that constitutional gene polymorphisms could play a role in this context. We report the pharmacogenetic ancillary study of the prospective COMET trial conducted in advanced BC patients (pts) receiving first-line Beva associated with paclitaxel. Methods: Relevant targeted gene polymorphisms were analyzed (blood) in 203 prospective pts (mean age 55.3, median follow-up 24 months). VEGFA at positions -2578C > A (rs699947), -1498T > C (rs833061), -634G > C (rs2010963), and 936C > T (rs3025039) were analyzed by PCR-RFLP. VEGFR1 319A > C (rs9582036), VEGFR2 at positions 604C > T (rs2071559), 1192C > T (rs2305948), 1416T > A (rs1870377), IL8 251T > A (rs4073), CYP2C8 139C > T (rs1572080), 399T > C (rs10509681) and ABCB1 at positions 1199 C > TA (rs2229109), 2677G > TAC (rs2032582) were analyzed by Mass-Array Agena. ABCB1 1236C > T (rs1128503) and 3435T > C (rs1045642) were analyzed by pyrosequencing. All fitted HWE. Results: Median progression-free survival (PFS) was 10.8 months. VEGFR1 319A allele was associated with longer PFS (p = 0.03). The VEGFA-1498T allele was significantly associated with both longer overall survival (OS) (p = 0.005) and PFS (p = 0.065). The VEGFA -2578C allele was associated with greater OS (p = 0.002) and PFS (p = 0.071). These two VEGFA polymorphisms were in linkage disequilibrium (p < 0.0001). Multivariate Cox analysis showed that VEGFA -2578 (p = 0.001) and VEGFR2 1416 (p = 0.025) were significant predictors of OS: the score of favorable alleles (VEGFA -2575C and VEGFR2 1416T) was highly associated with OS (p = 0.0003), with median survival at 24 months being 30% for score 0 (95%CI 15-61), 65% for score 1 (95%CI 55-75) and 90% for score 2 (95%CI 67-90). Conclusions: Application of an easy-to-perform low-cost genotyping test may identify strong predictors of Beva outcome in metastatic BC pts. In the current era of precision medicine, a pharmacogenetic-based personalized Beva therapy deserves to be prospectively validated in BC pts. Clinical trial information: 2012-A00244-39.

Assessment of multiple endocrine therapies for metastatic breast cancer in a multicenter national observational study

1052

Background: For HR+/HER2– metastatic breast cancer (mBC), International guidelines recommend multiple lines of endocrine therapy (ET) before starting chemotherapy. Few studies have assessed the efficacy of such strategy on large populations. Our objective was to evaluate multiple ET activity according to clinical and biological characteristics and type of ET. Methods: All patients (pts) who initiated treatment for a newly diagnosed mBC between January 2008 and December 2014 in all 18 French Comprehensive Cancer Centers were included in the real life ESME database. ESME collects retrospective data using a clinical trial-like methodology. Database lock was 8 Dec 2016. Primary endpoint of the current study was progression free survival (PFS) on successive ET lines. Only pts with ET alone were assessed (pts receiving ET after chemotherapy as maintenance therapy, or combined with targeted treatment were excluded). Results: 9921 pts out of 16703 in ESME, had HR+/HER2- mBC (median age 62.0 years[range 23-96]). 53.9% of pts had visceral and 80.1% non visceral disease at diagnosis. Median OS of HR+/HER2- pts was 42.15 months (95% CI, 40.93-43.27). As first-line therapy, 4123 pts (41.6%) received ET alone, while 2038 received chemotherapy alone (20.5%) and 3667 received both (37%). Median PFS for first-line ET (N=4123) was 11.3 months (95% CI, 10.6-11.9). Only 668 pts (16%) received subsequent lines of ET alone. Types of ET used are described in the table below. Successive PFS will be reported at the meeting. Conclusions: Those data show that ET is prescribed to less than 50% of patients with HR+/HER2- mBC in first line and only to a small minority in subsequent lines. This is not in line with existing guidelines (NCCN, ABC3). Real-life median PFS for first-line ET is consistent with median PFS reported in clinical trials (Nabholtz, 2000). [Table: see text]

Use of everolimus in advanced hormone receptor–positive metastatic breast cancer in a multicenter national observational study

e12548

Background: The everolimus-exemestane combination has been included in the International guidelines for advanced HR+ breast cancer (mBC) since the results of the Bolero-2 trial. Marketing authorization has been granted in France in July 2012 and reimbursement in Nov. 2014. Very few real life data of everolimus (EVE) use have been reported. Methods: All patients who initiated treatment for a newly diagnosed mBC between Jan. 2008 and Dec. 2015 in all 18 French Comprehensive Cancer Centers have been included in the real life ESME database, which collects retrospective data using a clinical trial-like methodology with quality assessments. Primary endpoint of the current analysis was to evaluate the incidence and indication of EVE use before and after marketing authorization and reimbursement Results: The ESME program included a total of 16,703 patients of which 9,921 had HR+/HER2- mBC. Median age at metastatic diagnosis was 62.0 year (range 23-96). Visceral metastases were present in 60.3% of cases. Only 4123 patients (41.6%) received endocrine therapy alone as first-line therapy, and 60% were deemed endocrine resistant Overall, 1,217 (12.3%) pts have received EVE during therapy as of Dec. 2015 (all lines). EVE was given as first line therapy in 117 pts (10% of all EVE pts and 1.2% of pts receiving a first line therapy). In 99/117 pts (85%) EVE was combined with exemestane. Before 2012, EVE was barely used and mostly within clinical trials. After 2012, use of EVE increased steadily (table). Percentages refer to the total of pts who received any kind of treatment during a given year of observation (e.g., 506/4435 pts took EVE in 2015). Median duration of EVE use was 6.0 months (0-65) as first line treatment and 3.9 months (0-65) in pretreated patients. Main causes of EVE cessation were recorded and will be detailed at the meeting. Conclusions: In this very large French national and representative cohort of HR+ HER2- mBC, EVE use rose quickly as soon as marketed. EVE was mostly used in pretreated mBC albeit in probably too advanced pts. These data underline the need for physician and patient education for oral therapies. [Table: see text]

Efficacy and long-term safety with bevacizumab included in neoadjuvant and adjuvant therapies in patients with advanced ovarian cancer: Results of the ANTHALYA trial

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Background: ANTHALYA showed that neoadjuvant Bevacizumab (B) added to Carboplatin and Paclitaxel (CP) was well tolerated and achieved encouraging complete resection rates at IDS (58.6%) in unresectable FIGO stage IIIC/IV ovarian, tubal or peritoneal adenocarcinoma (EJC 2017;70:133–42). We report response rates, PFS and long-term safety. Methods: Patients (pts) in ANTHALYA were randomized 2:1 to 4 cycles (c) of neoadjuvant CP ±3 c of B (15 mg/kg), IDS for eligible patients, then 1 c of CP + 3 c CPB + 21 c of B. Response and progression were evaluated by RECIST 1.1 using CT scan and CA-125. Circulating tumor cell counts (CTC) were evaluated at baseline, c2 and IDS. Results: 95 pts were treated in CP (n=37) or BCP (n=58) groups (mean study duration were 16.1 months [mo] and 16.9 mo, respectively). 80 pts (CP: 81% / BCP: 88%) had a CA-125 response (50% reduction in CA-125 level) before IDS. Objective response rates were 65% (62% CP / 67% BCP) before IDS (28 days after c4), 46% at c8 (46% CP/ 47% BCP) and 19% at c26 (19% CP/ 19% BCP). 24 (64.9%) CP pts and 26 (44.8%) BCP pts progressed during follow up (median PFS 21.2 mo [95%CI: 14.5, 26.7] and 23.5 mo [18.5, 30.6], respectively). Median PFS was respectively: 25.8 mo (21.0, 30.0) and 17.1 mo (13.5, 22.2) for pts with/without complete resection at IDS; 21.0 mo (15.0, 25.4) and 25.8 mo (18.5, 27.2) for pts with/without baseline CTCs (n=29 / 59); 21.8 mo (17.5, 27.1) and 22.2 mo (15.3, 38.0) for pts with FIGO IIIC and IV tumors. 36 pts did not receive adjuvant therapy within the study (21 were unresectable for IDS), 59 pts (57% CP / 66% BCP) received it. Of those, 34 pts (52% CP / 61% BCP) had Grade ≥3 adverse events including neutropenia (29% CP / 34% BCP), HBP (10% CP / 8% BCP), proteinuria (10% CP / 0% BCP), deep venous thrombosis (5% CP / 3% BCP), pulmonary embolism (0% CP / 8% BCP). Conclusions: Neoadjuvant BCP followed by IDS and adjuvant BCP achieves high response rates and extended PFS with an acceptable toxicity in this specific population of pts with FIGO stage IIIC/IV ovarian, tubal or peritoneal adenocarcinoma not eligible for primary debulking surgery. IDS outcome and CTC counts should be further explored as long term prognostic factors. Clinical trial information: NCT01739218.

Abstract PD1-06: Comparison of mutational landscapes of primary breast cancer and first metastatic relapse: Results from the ESOPE study

Background

Genomic profile of breast cancer metastases (M) may differ from that of the primary tumor (PT). In a multicenter prospective study (ESOPE, NCT 01956552) including 130 patients with biopsies of the first metastatic deposit, we have shown that luminal breast cancers are the most prone to phenotypical subtype changes (Comte et al, ASCO 2016#550). We report here the first results of a comparative PT/M targeted next generation sequencing (NGS) mutational analysis.

Methods

Of 130 patients, 117 paired PT/M samples obtained before any treatment were available for analysis. Targeted Sequencing was done using Illumina Hiseq2500 technology with a custom made 95 breast cancer associated genes panel. Sequence data were aligned to the human reference genome (hg19) using Bowtie2 algorithm. Median depth was 607X and 87% of targets achieved 100X depth. SNVs and indels were called using GATK UnifiedGenotyper. We retained COSMIC confirmed non synonymous, exonic/splice variants and observed at a frequency lower than 0,1% in population. Further confirmation of detected variants was performed with comparison to public databases (cbioportal, tumorportal), and potential pathogenicity was evaluated with 4 different public algorithms. We present here the results obtained from the first 35 matched PT/M samples (liver mets 68%), focusing analysis on 40 genes including PIK3CA (20 genes), ER (6 genes) and MAPK (11 genes) pathways, RUNX1, CDH1 and TP53 genes.

Results

Patients characteristics are representative of patients with first line metastatic breast cancer (Comte et al, ASCO 2016#550). Among the 40 genes analyzed in the 70 samples, we detected 134 somatic mutations (70 in PT and 64 in M) including 15 indels and 119 SNV. Among these 134 mutations there were 74 different mutations (66SNV and 8 indels) classified pathogenic for 26 and of unknown pathogenicity for 48 of them. We detected at least 1 mutation in 31 PT and in 28 M. Median numbers of mutations were 1 in PT (range 1-9) and 1 in M (range1-22) samples (p=0.295, Wilcoxon rank sum test). Top ten mutated genes in PT included PIK3CA, TP53, NCOR1, NF1, GATA3, CDH1, ERBB3, PTEN, HRAS, INPP4B. In M samples, the 10 top genes were PIK3CA, TP53, ERBB3, AKT3, CDH1, ERBB4, GATA3, INPP4B, MET, MTOR. Only 3 ESR1 mutations were detected, including 1 PT/M pair and 1 M. Beyond highly shared PIK3CA and TP53 mutations, overall crude PT/M discordance rate was 31%. Analysis by histological subtypes showed PT and M specific mutational profiles, suggesting a role in ERB gene family (notably ERBB3) and MAPK driven pathways in early metastatic progression. Specific metastatic site analysis suggested enrichment in MAPK pathway mutations in liver metastases when compared to other sites. Variant allelic fractions were globally not significantly different between PT and M samples.

Conclusion

In this prospective multicenter series of systematic biopsies of first metastases, we report a targeted mutational analysis of matched PT and M samples not modified by previous therapy exposure. Early analyses suggest specific genotypical changes according to tumor subtype and/or metastatic site. Extended and updated results will be reported at the meeting.

Citation Format: Cottu PH, Boulai A, Callens C, Baulande S, Legoix-Ne P, Bernard V, Vincent-Salomon A, Benhamo V, Brain EGC, Chemlali W, Campone M, Bachelot TD, Giacchetti S, Bonneterre J, Bidard F-C, Servois V, Comte A, Belin L, Sigal B, Bièche I. Comparison of mutational landscapes of primary breast cancer and first metastatic relapse: Results from the ESOPE study [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr PD1-06.

[Systemic neoadjuvant therapy of luminal breast cancer in 2016]

Neoadjuvant systemic therapies have been extensively evaluated in luminal breast cancer. Conventional cytotoxic chemotherapy increases breast conservation rate, albeit with a low level of complete pathological response of uncertain clinical significance. Endocrine therapies allow similar clinical results with much less side effects. Biological criteria of response to endocrine therapies are still being defined. The neoadjuvant setting must be used for early development of new compounds and to further document biological mechanisms of sensitivity and resistance to treatments.

Abstract P2-05-06: Clinical utility of systematic biopsy of first metastatic event in breast cancer: Results from a prospective multicenter trial

BACKGROUND: Cumulative evidence for phenotypic and molecular heterogeneity between primary breast cancer (BC) site and matched metastasis (mets) has been obtained in retrospective studies. Current expert consensus suggests performing biopsies of mets, but clinical utility and cost are unknown. The primary objective of the ESOPE study (NCT01956552) was to compare the phenotype and genotype of the primary tumor (PT) with those of matched mets at time of first distant relapse, before the start of any treatment, in order to optimize the treatment of mets

PATIENTS and METHODS: Between Nov. 2010 and Sept. 2013, we conducted a prospective multicenter study on BC patients (pts) with diagnosis of first mets. All pts were to have available Formalin-Fixed Paraffin-Embedded (FFPE) PT sample and mets accessible to either percutaneous or surgical sampling. All tissue samples were centrally analyzed with immunohistochemistry (ER, PgR, HER2, and Ki67) and FISH when indicated. Frozen samples were stored for further analyses. We recorded intended therapeutic decision before and after biopsy.

RESULTS: Of 93 pts included, 89 were eligible for biopsy. Median age was 57 years (28-81); median interval between PT and mets was 42 months (0-211), including 14 pts with novo metastatic breast cancer. Mets biopsy was performed in 85 pts (96%, refusal n=2, not feasible n=2). Toxicity was limited to only 1 grade 1 hemorrhage. Sampled sites were liver (44%), lung (16%), bone (13%), lymph node (13%), skin/muscle/chest wall (9%), ovary/peritoneum (4%), and adrenal gland (1%). PT was not available in 4 pts; mets biopsy was non contributive in 6 pts but led to a diagnosis of second primary cancer in 3 pts.

In 72 pts with matched PT and mets, PT were luminal A (n=11), luminal B (n=33), triple negative (n=13), HER2 (n=13), non-evaluable (n=2). Mets were luminal A (n=6), luminal B (n=30), triple negative (n=16), HER2 (n=14), non-evaluable (n=6). Discrepancy rates were: ER 18% [kappa for concordance =0.6, CI 95 % (0.42-0.77)], PgR: 39% [kappa=0.19, CI 95% (0.01-0.39)], Her2: 4% [kappa=0.86, CI 95% (0.7-1)], Ki67: 25% [kappa=0.19, CI 95% (-0.09; 0.49)].

The most frequent discrepancy rate was observed in pts with lum A PT, as only 3/10 developed Lum A mets. HER2 and triple negative were the most stable subtypes (12/13 and 12/12 respectively). Most importantly, mets biopsy led to a change in therapeutic decision in 25 pts (independent evaluation by 2 oncologists). Additional comparative targeted NGS analyses are ongoing on a first subset of 54 FFPE paired samples, and parallel whole exome sequencing is planned on 38 paired samples with available constitutional DNA.

CONCLUSION: Comparative analysis of breast cancer PT and first mets is routinely feasible, with very low morbidity and a significant impact for patients' management: 29% had a second cancer diagnosis or were proposed a therapeutic change. Furthermore, this study will provide additional data on quality and quantity of tissue available for molecular analysis, and ultimately in terms of cost-efficacy.

Citation Format: Comte A, Sigal-Zafrani B, Belin L, Bièche I, Callens C, Diéras V, Bidard F-C, Mariani O, Servois V, Szwarc D, Vincent-Salomon A, Brain ECG, Cottu PH. Clinical utility of systematic biopsy of first metastatic event in breast cancer: Results from a prospective multicenter trial. [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 P2-05-06.

Intra-tumor genetic heterogeneity and alternative driver genetic alterations in breast cancers with heterogeneous HER2 gene amplification

Background

HER2 is overexpressed and amplified in approximately 15% of invasive breast cancers, and is the molecular target and predictive marker of response to anti-HER2 agents. In a subset of these cases, heterogeneous distribution of HER2 gene amplification can be found, which creates clinically challenging scenarios. Currently, breast cancers with HER2 amplification/overexpression in just over 10% of cancer cells are considered HER2-positive for clinical purposes; however, it is unclear as to whether the HER2-negative components of such tumors would be driven by distinct genetic alterations. Here we sought to characterize the pathologic and genetic features of the HER2-positive and HER2-negative components of breast cancers with heterogeneous HER2 gene amplification and to define the repertoire of potential driver genetic alterations in the HER2-negative components of these cases.

Results

We separately analyzed the HER2-negative and HER2-positive components of 12 HER2 heterogeneous breast cancers using gene copy number profiling and massively parallel sequencing, and identified potential driver genetic alterations restricted to the HER2-negative cells in each case. In vitro experiments provided functional evidence to suggest that BRF2 and DSN1 overexpression/amplification, and the HER2 I767M mutation may be alterations that compensate for the lack of HER2 amplification in the HER2-negative components of HER2 heterogeneous breast cancers.

Conclusions

Our results indicate that even driver genetic alterations, such as HER2 gene amplification, can be heterogeneously distributed within a cancer, and that the HER2-negative components are likely driven by genetic alterations not present in the HER2-positive components, including BRF2 and DSN1 amplification and HER2 somatic mutations.

Electronic supplementary material

The online version of this article (doi:10.1186/s13059-015-0657-6) contains supplementary material, which is available to authorized users.

Abstract OT3-2-06: NEOPAL: A randomized phase II study comparing RCB response to neoadjuvant chemotherapy or letrozole-palbociclib in PAM50 defined postmenopausal luminal breast cancer

Background: HR-positive BC heterogeneously sensitive to neoadjuvant chemotherapy (NEC), with pCR rates varying from 2 to 20% at most. The alternative systemic primary therapy in ER+ breast cancer is neoadjuvant endocrine therapy (NET). Clinical response with NET is roughly 50%. It has also been suggested that NET may yield a higher rate of breast conserving surgery than NEC in ER+ disease, although pCR remains under 10% in both instances. No definite pathological criteria for response to NET has been defined so far. Within this context, the PAM 50 signature has been evaluated on numerous series of pts and has been shown to highly correlate with Residual Cancer Burden (RCB – Symmans, JCO 2007) and pCR in patients treated with NEC, as well as with the PEPI score in patients treated with NET (Ellis 2011). Palbociclib + Letrozole has been shown as a very active association as first-line metastastic treatment of HR+ Her2- BC pts on both response rates and progression free survival (Paloma-1 study). This combination could represent an interesting alternative to CT in carefully selected Luminal BC pts.

Trial design and statistical methods: Open-label, randomized, parallel, multicenter, exploratory phase II study, comparing sequential standard NEC (3 FEC 100 followed by 3 Docetaxel 100) and a same duration letrozole + palbociclib combination as neoadjuvant treatment of stage II-IIIA PAM 50 defined Luminal A-Node+/Luminal B breast cancer. Medical treatment will be followed by adequate surgery and complementary chemotherapy and radiation therapy as clinically indicated. All pts will receive adjuvant chemotherapy. Randomizations are equally balanced between the 2 arms and stratified based on T2 versus T3-T4 and PAM 50 luminal A vs luminal B. A Fleming 2-step statistical design will be used in the experimental arm with an intermediate futility analysis. The target accrual is 60 pts evaluable for RCB in both arms.

Eligibility criteria: Newly diagnosed pts with ER+, Her2-negative, stage II-III breast cancer will be tested for PAM50 signature. Only luminal A N+ or Luminal B (PAM50 ROR (Prosigna™) centralized evaluation) pts will be eligible and randomized. Pts must be post-menopausal women, aged &gt; 18 years, bear operable unilateral invasive BC, and not be candidate or uncertain for breast conservation.

Specific aims: The main objective of this trial is to evaluate the ability of each treatment strategy to provide RCB 0-I at surgery. Secondary end-points are: Clinical/radiological response rates in each treatment arm (RECIST 1.1), safety (CTC-AE V4.0), relative dose intensity of each drug in both arms, positive and negative predictive values of PAM50 ROR-defined status, assessment of several biomarkers as potential predictors of clinical and pathological response, rates of BCS, with regard to the initially planned surgery, all in both arms

Target accrual: This study has started in autumn 2014. 132 pts will have to be included (estimation of 10% risk of non evaluable pts). As about 10% of PAM50 evaluable pts will be classified as non luminal, and taking into account potential technical failures, about 180 pts will be screened.

Citation Format: Paul H Cottu, François Duhoux, Jérôme Lemonnier, Hervé Bonnefoi, Anne Vincent Salomon, Bernard Asselain, Suzette Delaloge. NEOPAL: A randomized phase II study comparing RCB response to neoadjuvant chemotherapy or letrozole-palbociclib in PAM50 defined postmenopausal luminal breast cancer [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr OT3-2-06.

Abstract P5-09-07: Identification of resistance-specific gene expression signatures in a breast cancer patient-derived xenograft with acquired resistance to different endocrine therapies

Background:

Acquired resistance to endocrine treatments (ET) occurs in more than 70% of cases of luminal breast cancer (LBC). We used patient derived xenografts (PDX) models of LBC to study molecular changes associated with acquired resistance to different ET modalities.

Methods:

A PDX model of LBC, established from an early stage BRCA2-mutated breast cancer, was treated with different ET (tamoxifen, fulvestrant, oophorectomy and letrozole) during several months. Tumors escaping to therapies were re-engrafted and maintained under therapy. ET-resistant and parental hormono-responders tumors were analyzed with immunohistochemistry (IHC), RT-PCR and Affymetrix Gene Expression Arrays. Hormono-resistant tumors were additionally studied for their in vivo response to ET, mTOR and PARP inhibitors.

Results:

From the initially ET sensitive HBCx22 xenograft model (Cottu, BCRT 2012) two resistant models were obtained respectively to tamoxifen (HBCx22-TamR) and to estrogen deprivation (HBCx22-OvaR). Unsupervised clustering of gene expression showed a clear cut separation between parental, TamR and OvaR tumors. Genes differentially expressed in TamR and OvaR tumors compared to parental HBCx22 were only partially overlapping. Up-Regulated genes in both TamR and OvaR tumors (n = 302) were involved in response to wounding, nucleotide metabolism, immune system, adhesion and cell growth. Biological Processes (BP) specifically deregulated in OvaR tumors (n = 380) included embryonic development, antigen presentation, amino acid and lipid metabolism. The top BP specifically regulated in TamR tumors (n = 1059) were response to estrogen and steroid hormones, TGF-b signaling, hypoxia, regulation of cell proliferation, with several strongly up-regulated genes of the histone clusters 1 and 3. Ingenuity Transcription Factor Analysis predicted activation of NFKB, SP1, AP-1 and JUN, and inhibition of ESR1. RT-PCR and IHC analyses confirmed the down regulation of ER controlled genes in the TamR tumors. Expression of ER co-regulators determined by RT-PCR showed that GREB1 was strongly reduced in TamR, while PBX1, GATA3 and FOXA1 were inhibited in OvaR. IHC analysis showed a loss of PTEN expression in HBCx22, with high levels of p-AKT and p-RPS6 in both parental and TamR and OvaR tumors. In vivo ET showed that the TamR xenograft was resistant to all modalities of ET, while OvaR was resistant to estrogen deprivation while retaining some sensitivity to tamoxifen and fulvestrant. Treatment with the mTOR inhibitor RAD001 arrested tumor growth but did not show any additive effect when combined to ET in TamR or OvaR tumors. Conversely, the combination of RAD001 with Olaparib was highly synergistic and induced complete tumor response in 70% of mice.

Conclusions:

According to the therapeutic selection, tumors derived from a PDX model of ER+ breast cancer show specific resistance patterns and gene expression profiles including disruption in the ER transcriptional program. The analysis of additional resistant tumors established from a second ER+ PDX will be presented at the meeting.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P5-09-07.

Aromatase inhibitor pain syndromes: Classification and determination of specific risk factors—A prospective multicenter cohort study

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Background: Pain is frequent during Aromatase Inhibitors (AIs) treatment for breast cancer and several pain syndromes have been reported but not precisely defined. We developed a prospective multicentre study aiming at classifying AIs-related pain syndromes, comparing their impact on daily life, and identifying their specific determinants for a more targeted prevention approach. Methods: A one-year multicenter cohort prospective study, with 5 pre-scheduled visits, was carried out in early stage breast cancer women, free of pain, starting an AI treatment, recruited from 4 oncology centres. At baseline, clinical data (demography and psychosocial, cancer characteristics and treatments, pain, sleep, rheumatologic examination, cancer-related quality of life), biological data (sex hormones, vitamin D, bone biomarkers, oxidative stress, immunological and inflammatory markers), and genetic polymorphism for pain mechanisms (opioid and serotonin pathways) were recorded. Results: A cohort of 135 women was evaluated. Among them, 77 (57%) developed a pain syndrome along the study period, leading to AIs discontinuation in 12 cases. Five main different types of pain syndromes were identified: joint pain, in 48 women overall over the follow-up (36%), diffuse pain, in 30 women (22%), tendinitis, in 29 women (22%), and neuropathic pain, in 12 women (9%) and mixed types, which were frequent and often transient. Analyses demonstrated that risk factors for developing pain syndromes were baseline anxiety and impaired quality of life, while cancer features, genetic background, inflammation, immunological and sex hormone levels were not involved. Conclusions: In pain-free women with breast cancer starting an AI, risks for developing pain during the first year of treatment are slightly greater than 50%. We identified 5 main pain syndromes, joint and widespread pain being the most frequent. In all instances, initial psychological dimensions (personality, impaired quality of life and anxiety) are identified as major risk factors for pain development.