Prognostic Significance of Adjuvant Chemotherapy Induced Amenorrhea in Luminal A and B Subtypes.

Objective: In this retrospective study, chemotherapy induced amenorrhea in patients with early stage breast cancer and its effects on survival were investigated.
Materials and Methods: Two hundred fifty-two patients received adjuvant chemotherapy without ovarian suppression treatment (OST) from 600 premenopausal patients were included in the study. Patients were divided into two groups; with amenorrhea and without, and compared with clinicopathologic features and survival. SPSS version 17 was used.
Results: Chemotherapy-induced amenorrhea (CIA) was observed in 145 (57.5%) of 252 patients who received no OST during follow-up. The 5-year OS rate of patients with CIA was significantly higher than patients without CIA (p= 0.042, 95.9% vs. 89.7% vs. 158.88 vs. 135.33 months, respectively). In the subgroup analysis, the OS in patients with hormone receptor (+) was significantly higher than in those receptor (-) in patients with CIA (p=0.011, 97.5% vs. 90.9% vs. 162.13 vs. 126.16 months, respectively). The OS was significantly longer in the luminal A molecular subtype than in those with luminal B molecular subtype, in patients with CIA, but the difference was not significant in patients without CIA (p=0.027 vs. p=0.074, respectively).
Conclusion: As a conclusion; survival advantage of the chemotherapy induced amenorrhea more pronounced with hormone receptor positivity, lymph node involvement, and advanced disease over patients who do not develop amenorrhea. This advantage of amenorrhea development further prolongs survival compared with luminal B in the luminal A molecular subtype.
Competing Interests: Conflict of Interest: The authors have no conflicts of interest to declare.