Comparison of clinicopathological features and treatments between pre- and postmenopausal female breast cancer patients – a retrospective study

Introduction
To find out if there are clinical and biological differences in breast cancer characteristics of premenopausal and postmenopausal women. For this reason, we investigated the differences in terms of the clinicopathological features and treatment methods of premenopausal and postmenopausal breast cancer patients in our study.

Material and methods
In this study, the files of 428 patients who were operated due to breast cancer between 1 January 2007 and 31 December 2017 in Ankara Atatürk Training and Research Hospital were examined retrospectively. The age, tumour size, tumour grade, oestrogen receptor, progesterone receptor, HER2 score, Ki-67 proliferation index, perineural invasion, and lymphovascular invasion were investigated.

Results
In patients with premenopausal breast cancer, the tumour diameter was larger (p = 0.047) and the lymph node metastasis was higher (p < 0.001). Oestrogen receptor (OR) expression (p = 0.002), progesterone receptor (PR) expression (p = 0.014), negative human epidermal growth factor receptor 2 (HER2) expression (p = 0.038), and Ki-67 expression (p = 0.017) were higher in the premenopausal group. In the premenopausal group, breast conserving surgery (p = 0.004), chemotherapy (p = 0.007), radiotherapy (p = 0.008), and endocrine therapy (p = 0.025) were higher than in the postmenopausal group.

Conclusions
Premenopausal and postmenopausal female breast cancer patients have significant differences in tumour size, tumour grade, axillary lymph node metastasis, hormone receptor status, HER2 expression, and treatment modalities.