282P - Impact of pembrolizumab on ovarian function in young triple negative breast cancer patients treated with chemo-immunotherapy

Background

Pembrolizumab in combination with neo-adjuvant chemotherapy is a new standard in non-metastatic triple negative breast cancers (TNBC). Most patients with non-metastatic TNBC will survive. Preclinical data show a reduction in the number of primordial follicles following exposure to pembrolizumab. Anti-Müllerian Hormone (AMH) is used to determine ovarian reserve, and its level decreases by almost 90% after exposure to chemotherapy in young breast cancer patients. We sought to assess the impact of pembrolizumab on AMH values in young TNBC patients.

Methods

In this monocentric retrospective study, we included TNBC patients under 43 years of age for whom plasma samples were available before and after treatment. We assessed their AMH, FSH and oestradiol values before (baseline) and at the end of exposure to carboplatin/paclitaxel/epirubicin/cyclophosphamide plus pembrolizumab (P-CT group). These results were compared with those of a retrospective cohort of early TNBC patients under 43 years of age, treated with cyclophosphamide/anthracycline/taxanes but without pembrolizumab (No P group).

Results

Thirteen patients were included in the P-CT group and compared with 67 patients in the No P group. Median age (35y) and BMI (23 kg/m2) were comparable in both groups. Baseline AMH was 1.08 ng/mL in the P-CT group, and 1.4 ng/mL in the No P group (p=0.2). One year after the start of treatment, AMH fell significantly to 0.015 ng/mL (p<0.001 vs baseline) and 0.018 ng/mL (p<0.001), in the P-CT and No P groups, respectively. Notably, 5/13 patients (38%) had undetectable AMH (<0.01 ng/mL) after treatment in the P-CT group and 23/67 (34%) in the No P group. At baseline, no differences were observed between the two groups in FSH and oestradiol values. FSH increased significantly (p<0.001), and oestradiol tended to decrease significantly (p=0.07) after exposure to treatment, with no difference between the P-CT and No P groups.

Conclusions

In this cohort, no impact of the addition of pembrolizumab to standard chemotherapy on the evolution of AMH, FSH or oestradiol before and after treatment was observed in young TNBC patients.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

Centre Henri Becquerel.

Funding

Has not received any funding.

Disclosure

F. Clatot: Financial Interests, Personal, Advisory Board: Merck, BMS, MSD, Gilead, AstraZeneca, Novartis, Daiichi, Roche, Eli Lilly. All other authors have declared no conflicts of interest.