Breast cancer in young women: pathologic and immunohistochemical features.

- A young woman with breast cancer is considered to be a woman younger than 40. According to the literature, breast cancer in the population of young women usually is of a higher histologic grade, unfavorable hormonal status, and overall higher mortality rate when compared with breast cancer occurring in older population. We compared pathologic and immunohistochemical features of breast carcinoma in women under 40 years of age with the respective features in women over 60 years of age. The following parameters were observed in these two groups: tumor size, lymph node status, histologic grade, hormonal receptor status, Ki-67 prognostic index, Her2/neu status, and histologic type of the tumor. Early onset breast carcinoma was found to have a higher frequency of tumor grade 3 (29% vs. 17%) and estrogen receptor negativity (45% vs. 23%). In the group of young women, breast carcinoma was mostly multicentric (23% vs. 5%), triple-negative (32% vs. 10%), and was found to have higher proliferation index Ki-67 (25% vs. 10%). Our results confirmed differences between the young and older groups of patients. In the group of young women, we found predominantly unfavorable prognostic parameters of the disease.