Abstract P4-11-20: Attitudes and factors influencing contraception use over time in premenopausal women with early breast cancer in the prospective CANTO study

BACKGROUND: With an increased lifespan, survivorship has become a crucial component of breast cancer (BC) care. Among survivorship concerns, adequate contraception counseling is needed in premenopausal patients (pts) not seeking to become pregnant. However, very limited evidence exists on attitudes and factors influencing contraception use over time in premenopausal women with early BC. METHODS: CANTO is a multicenter, prospective cohort study of 12,012 pts with stage I-III BC (NCT01993498). This analysis included women aged ≤50 years with known premenopausal status at BC diagnosis. Contraception use and type were longitudinally evaluated at diagnosis, year-1 (T1) and 2 (T2) after diagnosis. Multivariable logistic regression models assessed associations between clinical, socio-economic, treatment, toxicity (CTCAE) and pts-reported outcome (PROs, EORTC QLQ-C30/BR23) variables, with contraception use after diagnosis. RESULTS: Among 2,900 pts included, mean age at diagnosis was 43.1 (SD 5.6) years, 96.0% of pts already had children at BC diagnosis, 70.8% and 80.0% received chemotherapy and endocrine therapy (ET), respectively. Among patients treated with ET, 80.2% received tamoxifen alone and 19.8% other therapies (either tamoxifen or an aromatase inhibitor or a combination) plus ovarian function suppression (OFS). Following diagnosis, 45.0% of pts at T1 and 65.7% at T2 reported consulting a gynecologist. At diagnosis, 54.2% of pts reported contraception use, with the majority (62.6%) using hormonal methods. Prevalence of contraception use significantly decreased at T1 and T2 (38.9% and 41.2%, respectively; ptrend Citation Format: Matteo Lambertini, Claudia Massarotti, Julie Havas, Barbara Pistilli, Anne-Laure Martin, Alexandra Jacquet, Charles Coutant, Florence Coussy, Asma Dhaini Merimeche, Florence Lerebours, Olivier Tredan, Christelle Jouannaud, Olivier Rigal, Marion Fournier, Patrick Soulie, Maria Alice Franzoi, Lucia Del Mastro, Ann H. Partridge, Fabrice Andre, Ines Vaz-Luis, Antonio Di Meglio. Attitudes and factors influencing contraception use over time in premenopausal women with early breast cancer in the prospective CANTO 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 P4-11-20.