Abstract 128P
Background
There is limited data regarding differences in characteristics, gBRCA, patterns of care and survival according to age at BC diagnosis in young women ≤40yrs.
Methods
Retrospective multicenter hospital-based cohort study including young women (≤40yrs) diagnosed with stage I-III BC during 2000-2016 and treated in two Belgian hospitals. Data on baseline characteristics, treatments, and survival outcomes were collected. We calculated adjusted hazard ratios (aHR) for distant recurrence-free interval (DRFI), overall survival (OS), cumulative incidence of locoregional relapse (LR), second primary BC (SPBC) and non-BC (SPNBC) with multivariable analysis adjusting for factors that differed within groups.
Results
Of 1849 patients (pts) included, 9.4%, 25.1% and 65.5% were in age groups <30yrs (I), 30-34yrs (II) and 35-40yrs (III), respectively. In 1009 pts (54.5%) with known gBRCA, 14.6% had a pathogenic variant in BRCA1 and 8.3% in BRCA2, with no significant differences within age groups. Median follow-up was 10.1yrs (IQR 5.7-14.4). Compared to pts in group III, pts in group I and II had worse DRFI (aHR 1.38 [1.01-1.87]; aHR 1.30 [1.04-1.61]) and OS (aHR 1.51 [1.03-2.2]; aHR 1.34 [1.02-1.7]), respectively. Similar rates of SPBC and SPNBC were observed among age groups. Risk of LR was higher in group I vs group III (aHR 1.86 [1.14-3.04]). There was no independent prognostic value of gBRCA-mutated vs wild-type pts for DRFI (aHR 1.21 [0.90-1.62]), OS (aHR 0.85 [0.56-1.28]), LR (aHR 0.72 [0.42-1.24] or SPNBC (aHR 1.79 [0.78-4.12]), but pts in the gBRCA subgroup had significantly higher rates of SPBC (aHR 14.32 [10.1-20.2]). There was a significant decrease over time in the proportions of pts in group III, with unknown gBRCA, receiving breast-conserving surgery and adjuvant or no chemotherapy (CT). Rates of neoadjuvant CT use and ovarian function suppression increased over time. There was no significant difference in outcomes over time after excluding HER2+ pts who did not receive anti-HER2 therapy.
Conclusions
Very young pts with BC (<35yrs) have a higher risk of distant recurrence and worse overall survival compared to those 35-40yrs. Special attention is needed to manage very young and young pts with BC.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
Kevin Punie, Evandro de Azambuja, Matteo Lambertini.
Funding
Fondation Lambeau-Marteaux (Université Libre de Bruxelles, ULB) (Ref. SA/02012021).
Disclosure
K. Punie: Financial Interests, Institutional, Advisory Board: AstraZeneca; Financial Interests, Institutional, Advisory Board: Novartis; Financial Interests, Institutional, Advisory Board: Pfizer; Financial Interests, Institutional, Advisory Board: Roche; Financial Interests, Institutional, Invited Speaker: Roche; Financial Interests, Institutional, Invited Speaker: Novartis; Financial Interests, Institutional, Advisory Board: Vifor Pharma; Financial Interests, Institutional, Advisory Board: Eli Lilly; Financial Interests, Institutional, Invited Speaker: Eli Lilly; Financial Interests, Institutional, Invited Speaker: Mundi Pharma; Financial Interests, Institutional, Advisory Board: Pierre Fabre; Financial Interests, Institutional, Advisory Board: McCann Health; Financial Interests, Institutional, Advisory Board: Roularta; Financial Interests, Institutional, Funding: Sanofi; Non-Financial Interests, Principal Investigator: EORTC 1745-ETF-BCG trial; Non-Financial Interests, Other, Committee member: ESMO Young Oncologists Committee; Non-Financial Interests, Invited Speaker: BSMO; Non-Financial Interests, Advisory Role: Commission personalized medecine Federal Government Belgium. H. Wildiers: Financial Interests, Institutional, Other, Consultancy fee: AbbVie; Financial Interests, Institutional, Invited Speaker: Ariez; Financial Interests, Institutional, Advisory Board: AstraZeneca; Financial Interests, Institutional, Advisory Board: Biocartes; Financial Interests, Institutional, Advisory Board: Daiichi Sankyo; Financial Interests, Institutional, Expert Testimony: DNA Prime; Financial Interests, Institutional, Advisory Board: EISAI; Financial Interests, Institutional, Other, Consultancy fee: Immutep Pty; Financial Interests, Institutional, Advisory Board: KCE; Financial Interests, Institutional, Advisory Board: Lilly; Financial Interests, Institutional, Advisory Board: MSD; Financial Interests, Institutional, Advisory Board: Novartis; Financial Interests, Institutional, Advisory Board: Orion corporation; Financial Interests, Institutional, Advisory Board: Pfizer; Financial Interests, Institutional, Advisory Board: PSI Cro AG; Financial Interests, Institutional, Advisory Board: Puma technology; Financial Interests, Institutional, Advisory Board: Roche; Financial Interests, Institutional, Advisory Board: Sirtex; Financial Interests, Institutional, Research Grant: Novartis; Financial Interests, Institutional, Research Grant: Roche; Financial Interests, Institutional, Invited Speaker, Travel: Pfizer; Financial Interests, Institutional, Invited Speaker, Travel: Roche. P. Neven: Financial Interests, Institutional, Other, Consultancy: Pfizer; Financial Interests, Institutional, Other, Consultancy: Novartis; Financial Interests, Institutional, Other, Consultancy: Eli Lilly; Financial Interests, Institutional, Other, Consultancy: Roche; Financial Interests, Institutional, Other, Consultancy: AstraZeneca; Financial Interests, Institutional, Advisory Board: Pfizer; Financial Interests, Institutional, Advisory Board: Novartis; Financial Interests, Institutional, Advisory Board: Lilly; Financial Interests, Institutional, Advisory Board: Roche; Financial Interests, Institutional, Sponsor/Funding: KOTK. E. de Azambuja: Financial Interests, Institutional, Advisory Board: Roche/GNE; Financial Interests, Institutional, Advisory Board: Novartis; Financial Interests, Institutional, Advisory Board: Seattle Genetics; Financial Interests, Institutional, Advisory Board: Zodiacs; Financial Interests, Institutional, Advisory Board: Lilly; Financial Interests, Institutional, Advisory Board: Pierre Fabre; Financial Interests, Institutional, Advisory Board: Libbs; Financial Interests, Institutional, Other, travel grant: Roche/GNE; Financial Interests, Institutional, Other, travel grant: GSK/Novartis; Financial Interests, Institutional, Research Grant: Roche/GNE; Financial Interests, Institutional, Research Grant: AstraZeneca; Financial Interests, Institutional, Research Grant: Novartis; Financial Interests, Institutional, Research Grant: Servier. M. Lambertini: Financial Interests, Institutional, Advisory Role: Roche; Financial Interests, Institutional, Advisory Role: Novartis; Financial Interests, Institutional, Advisory Role: Lilly; Financial Interests, Institutional, Advisory Role: AstraZeneca; Financial Interests, Institutional, Invited Speaker: Roche; Financial Interests, Institutional, Invited Speaker: Novartis; Financial Interests, Institutional, Invited Speaker: Lilly; Financial Interests, Institutional, Invited Speaker: Pfizer; Financial Interests, Institutional, Invited Speaker: Takeda; Financial Interests, Institutional, Invited Speaker: Sandoz. All other authors have declared no conflicts of interest.