Abstract 132P
Background
Patients with HR+ BC with unfavourable features have an increases risk of relapse. Our aim was to describe clinico-pathological characteristics, adjuvant treatments and survival outcomes of patients with high-risk HR+ BC, using RW data reported in the Cancer Toxicities (CANTO) prospective observational study (NCT01993498).
Methods
Baseline features and treatment patterns were collected from CANTO cohort for all women with HR+ BC at high-risk of relapse defined either (1) ≥ 4 positive pathologic axillary lymph nodes (LN) or (2) 1 to 3 positive axillary LN with a tumor size ≥ 5 cm or grade III. HR+ BC not respecting these criteria were classified as non-high risk. Invasive disease free survival (IDFS) and distant metastasis free survival (DMFS) were calculated. Bilateral BC were excluded.
Results
Among HR+ BC patients, 1266 (15.0%) were at high-risk of relapse. The median age at diagnosis was 54.3 yrs (range 22-87), 589 (47.2%) were premenopausal, and 79.9% had a favorable Charlson comorbidity score. Germline BRCA1 or BRCA2 mutations were reported in 3.5% and 8.0%, respectively. 617 patients (49.0%) had ≥ 4 positive LN, 327 (26.0%) had tumor size ≥ 5 cm and 727 (57.6%) grade III tumors. 1192 (94.2%) received (neo)adjuvant chemotherapy (1155 with anthracyclines-based regimens) and 97.3% had endocrine therapy (56.1% with aromatase inhibitors). Notably, 33.8% discontinued endocrine therapy (ET) for adverse events. The table reports the survival rates. Table: 132P
After a median follow up of 6.2 yrs
| High-risk HR+ BC | Non-high risk HR+BC | |
| 5y-IDFS | 80.9% | 93.6% |
| 10y-IDFS | 67.6% | 78.1% |
| 5y-DMFS | 84.4% | 96.8% |
| 10y-DMFS | 72.2% | 85.9% |
Conclusions
This RW data showed that patients with high-risk HR+ BC have a considerable risk of relapse and lower event free survival, which highlights the potential benefit of adding new therapies in the adjuvant setting. Rate of treatment discontinuations due to ET-related adverse events underscores the importance of a support system to manage adverse events adequately.
Clinical trial identification
NCT01993498.
Legal entity responsible for the study
Unicancer.
Funding
The CANTO project was supported by the French Government under the “Investment for the Future” program managed by the National Research Agency (ANR), grant n° ANR-10-COHO-0004. The present high-risk group analysis was funded by Eli Lilly, and the analysis independently performed by Unicancer group.
Disclosure
M. Campone: Financial Interests, Personal, Advisory Board: AstraZeneca, Novartis, ABBVIE, Sanofi, Lilly, Pfizer, Sandoz, Accord, G1 Therapeutic, Seagen, Gilead, Daiichi Sankyo; Financial Interests, Personal, Other, Consultant: Pierre Fabre Oncology, Sanofi, Novartis, Servier, Daiichi Sankyo, pet-therapy; Financial Interests, Personal, Speaker’s Bureau: Novartis, Lilly; Non-Financial Interests, Personal, Other, travel: Pfizer, Novartis, Roche, AstraZeneca. G. Curigliano: Financial Interests, Personal, Other, honoraria: Ellipses Pharma; Financial Interests, Personal, Advisory Role: Roche/Genentech, Pfizer, Novartis, Lilly, Foundation Medicine, Bristol Myers Squibb, Samsung, AstraZeneca, Daiichi Sankyo, Boehringer Ingelheim, GSK, Seattle Genetics, Guardant Health, Veracyte, Celcuity, Henfrui Therapeutics, Merck, Exact Sciences, Blueprint Medicines, Gilead Sciences; Financial Interests, Personal, Speaker’s Bureau: Roche/Genentech, Novartis, Pfizer, Lilly, Foundation Medicine, Samsung, Daiichi Sankyo, Seagen, Menarini, Gilead Sciences, AstraZeneca, exact sciences; Financial Interests, Institutional, Sponsor/Funding: Merck; Financial Interests, Personal, Other, travel, accomodation: Roche/Genentech, Pfizer, Daiichi Sankyo, AstraZeneca. B. Pistilli: Financial Interests, Personal, Advisory Board: AstraZeneca, Novartis, Myriad Genetics, Pierre Fabre; Financial Interests, Personal, Invited Speaker: Novartis, AstraZeneca, MSD Oncology, Pfizer; Financial Interests, Personal and Institutional, Sponsor/Funding: Daiichi Sankyo, Puma Biotechnology, Novartis, Merus, Pfizer, AstraZeneca. E. Rassy: Financial Interests, Personal, Other, travel, accomodations, expenses: Pfizer, Roche, Mundipharma, Eli Lilly, Novartis; Financial Interests, Institutional, Sponsor/Funding: Gilead; Financial Interests, Personal, Other, honoraria: Eli Lilly, Seagen, Novartis. All other authors have declared no conflicts of interest.