6P - Prognostic outcomes of concurrent GnRH agonist use with chemotherapy

Date 08 May 2014
Event IMPAKT 2014
Session Welcome reception and Poster Walk
Topics Anti-Cancer Agents & Biologic Therapy
Breast Cancer, Early Stage
Presenter Soo Youn Bae
Citation Annals of Oncology (2014) 25 (suppl_1): i2-i2. 10.1093/annonc/mdu062
Authors S.Y. Bae, J. Kim, S.K. Lee, W.H. Kil, S.W. Kim, J.E. Lee, S.J. Nam
  • Department Of Surgery, SAMSUNG MEDICAL CENTER, 135-710 - Seoul/KR

Abstract

Background:

Concurrent endocrine therapy with chemotherapy had a concern of potential antagonism between them, therefore the sequential addition of endocrine therapy to chemotherapy was recommended. However, gonadotropin-releasing hormone (GnRH) agonist has been used concurrently with adjuvant chemotherapy as a therapeutic option to prevent premature ovarian failure in young premenopausal patients with breast cancer. The aim of this study was to determine the impact of concurrent use of GnRH agonists with adjuvant chemotherapy on relapse-free and overall survival, and thus to establish the oncologic safety of ovarian protection with GnRH agonists.

Methods:

Medical records of patients with invasive breast cancer who underwent surgery from January 2002 to April 2012 were retrospectively reviewed. Among them, premenopausal women aged between 20 and 40 years who received adjuvant chemotherapy after surgery were included for analysis, regardless of lymph node metastasis or hormone receptor (HR) status. Patients were classified into two groups; One which were treated with GnRH agonists for ovarian protection during chemotherapy, and the other which underwent chemotherapy without ovarian protection. Due to the discrepancy in sample sizes and clinical characteristics of the two groups, a propensity score matching strategy was used to create matched sets of the two groups with almost similar age, pathologic stage, HR status, and Her2 status.

Results:

A total of 101 patients treated with concurrent GnRH agonist during chemotherapy were compared with 335 propensity score matched patients. Among the patients, 81.2% were younger than 35 years, 34.7% were stage I and 58.4% were stage II. Of the patients, 58.4% were hormone responsive. Survival analysis using stratified Cox regression showed that women treated with concurrent GnRH agonists had better recurrence-free survival after adjustment (HR 0.21, 95% CI 0.07-0.68, p = 0.009), but that GnRH treatment did not affect overall survival (HR 0.12, 95% CI 0.09-1.69, p = 0.118).

Conclusions:

Ovarian protection using GnRH agonists can be safely considered for young women with breast cancer in terms of oncologic outcomes. Further studies are needed to assess the long-term outcomes of concurrent GnRH agonist use with chemotherapy.

Disclosure:

All authors have declared no conflicts of interest.