Survival outcome of combined GnRH agonist and tamoxifen is comparable to that of sequential adriamycin and cyclophosphamide chemotherapy plus tamoxifen in premenopausal patients with early breast cancer.

Survival outcome of ovarian suppression plus tamoxifen has been shown to be comparable with chemotherapy in premenopausal women; however, there are a few previous studies that compared this treatment to the current standard adriamycin and cyclophosphamide (AC) regimen. The aim of the present study was to compare the survival outcome of gonadotropin-releasing hormone (GnRH) agonist plus tamoxifen (GnRH-TAM) and chemotherapy AC plus tamoxifen (AC-TAM) in premenopausal patients with early breast cancer who were hormone receptor-positive. Premenopausal patients with early breast cancer who were treated at The Siriraj Hospital between January 2005 and December 2015 were retrospectively recruited. The inclusion criteria included newly diagnosed breast cancer, size ≤3 cm, node-negative and hormone receptor-positive. All patients received adjuvant systemic therapy and were divided into two groups. In the GnRH-TAM group, the patients received subcutaneous injection of 10.8 mg of goserelin every 3 months for 2-3 years and TAM (20 mg/day) for 5 years. In the AC-TAM group, AC was administered every 3 weeks for 4 cycles followed by TAM (20 mg/day) for 5 years. In total, 40 patients received GnRH-TAM and 130 patients received AC-TAM. The mean age at diagnosis was 44.4±6.3 years while the median follow up time was 77 (36-167) months. There was no mortality in either group and no significant difference in disease-free survival between the two groups. No adverse effect occurred and good compliance was observed in all patients who received GnRH-TAM. Treatment with GnRH-TAM resulted in a comparable survival outcome and better quality of life compared with AC-TAM.