Abstract P5-15-06: 10-year follow-up of adjuvant ovarian suppression in high risk premenopausal breast cancer

Abstract

Abstract Background: A large randomized study has shown the value of temporary ovarian suppression during the administration of chemotherapy in the treatment of high risk estrogen receptor positive (ER+) breast cancer (BC) (Pagani et al. N Engl J Med 2014). In another study ovarian suppression added to chemotherapy appeared to protect ovarian function (Moore et al. N Engl J Med 2014) and improve the expected outcome of estrogen receptor negative (ER-) BC. Nevertheless, both these studies have a median follow-up time limited to 68 months and 49 months, respectively. Here we present the data of a large non randomized phase II study of adjuvant ovarian suppression in ER+ and ER- breast cancer with a median follow-up of 120 months (range 90-220 months). The primary end point was the ovarian function preservation rate, secondary end points were disease-free survival (DFS) and overall survival (OS). Methods: Between 06-1997 and 06-2007, 200 premenopausal, high risk early BC patients entered the study. All patients received the LH-RH analogue before starting chemotherapy. Breast conserving and radical surgery were performed in 74% and 26% of patients, respectively. Systemic therapy was tailored to the biological characteristics of each patient, and followed by radiation therapy and hormonal therapy in ER+ tumors. Results: The median patient's age was 43 years (range 26-45). The mean number of positive axillary nodes was 3.2 (range 1-25). Seventy-one % of patients were ER+ and/or progesterone receptor positive (PGR+), 29% were ER - and PGR-. The median KI-67 was 30% (range 15% -100%). Twenty-one % of patients were c-ErbB-2 positive. After a median follow up of 120 months (range 90-220), normal menses returned in 90% of patients younger than 40 years and in 56% of patients older than 40 years. The 10 and 15-year DFS rate were 85.5% and 71%, respectively, while the 10 and 15-year OS rate were 91%, and 71%, respectively. The standard pattern of toxicity of chemotherapy was observed. Hot flashes and G1 osteopenia occurring after LH-RH analogue administration were temporary and subsided after the cessation of therapy. Conclusions: LH-RH administration, concurrent with chemotherapy is tolerable and effective. Five full term pregnancies were documented. A favourable impact on the expected DFS and OS was observed. ER- patients had late new primaries, but no recurrence after 5 years, while ER+ patients had disease recurrence even after 13 years. Citation Format: Recchia F, Candeloro G, Rosselli M, Bratta M, Rea S. 10-year follow-up of adjuvant ovarian suppression in high risk premenopausal breast cancer. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P5-15-06.