Abstract P6-16-02: Fertility preservation in young breast cancer patients: Real life data on 1390 patients treated in the Institut Curie

Introduction: Adverse effects of chemotherapy on fertility are a critical concern for young breast cancer (BC) patients. Fertility preservation (FP) is currently offered to BC patients, though literature data concerning reproductive outcomes are scarce. Also, very few data are available on whether these procedures are associated with delay to treatment, or whether they impact oncologic outcomes. The objective of our study is to evaluate: (i) efficacy of FP procedures in terms of stored material and pregnancy rates, (ii) safety regarding time from BC diagnosis to chemotherapy, and oncologic outcomes in a large real-life cohort of BC patients.

Methods: We retrospectively analyzed medical charts of all consecutive patients aged between 18 and 43 diagnosed with invasive BC between 01/01/2011 and 30/09/2017 and treated with chemotherapy at Institut Curie (Paris and Saint Cloud). Baseline factors (antral follicle count (AFC), AMH), details on fertility preservation procedures, and results (number of frozen oocytes and embryos) were retrieved in 3 academic hospitals (Jean Verdier, Antoine Béclère and Cochin). All medical charts were reviewed in March 2018 to assess time from diagnosis to surgery / chemotherapy, pregnancy outcomes, recurrence and survival. We compared time from first consultation to start of chemotherapy (time diagnosis-to-CT) in case of neoadjuvant chemotherapy (NAC between patients who had or who did not have PF.

Results: On 1.390 patients identified, 622 had NAC, 768 had adjuvant CT. Median age at diagnosis was 38.8 y.o. 136 were BRCA mutated.

- 264 patients (19%) underwent a FP procedure: In Vitro Maturation (IVM) (58%, n=154); ovarian stimulation protocol (STIM) (31%, n=82); others (10%, n=28). The mean number of oocytes preserved was 5 [0-36] and was not different between IMV and STIM.

- Delays from diagnosis to CT were not different in patients who had FP than those who did not, neither in patients with NAC (no FP: 24.1 days VS FP: 22.8, p=0.24) nor in patients with adjuvant CT (no FP: 70.6 days VS FP : 66.8, p=0.11).

- 39 patients had at least one pregnancy: 28 spontaneous, 6 without information, and 5 from oocyte/embryo donation. The pregnancy rate was higher in patients in FP group (n=16 ; 6%) than in no FP group (n=23 ; 2%). 3 reused material : 2 without pregnancy and one had a miscarriage.

- About oncologic outcomes, 90 patients underwent relapse (6,4%), and this rate was not significantly different in the 2 groups (n=12, 4,5% VS n=78, 6.9%).

- Patients with BRCA mutation (BRCAm) had lower AMH (2.9 VS 4.1 ng/mL ; p = 0,03) and antral follicle count (17.6 VS 24 ; p = 0.01). However, there was no difference on the stored material, and pregnancy rate was higher than in patients with no mutation or unkwnown status (7.6 VS 2.6% ; p = 0,01).

Conclusion: Pregnancy rate was higher in patients with FP, however majority of pregnancies was spontaneous, and no live birth was observed after material reuse. FP procedures were not associated with delay to treatment. Though bias cannot be excluded, preliminary data do not show an adverse impact of FP on oncologic outcome. Further follow-up is needed.

Citation Format: Hamy-Petit A-S, Toussaint A, Sautter C, Coussy F, Donnadieu A, Rouzier R, Saule C, Frank S, Bensen A, Grynberg M, Scarabin-Carre V, Santulli P, Balezeau T, Guerin J, Reyrat E, Jamain C, Hours A, Lecourt A, Reyal F. Fertility preservation in young breast cancer patients: Real life data on 1390 patients treated in the Institut Curie [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 P6-16-02.