Clinicopathologic features and molecular subtypes of breast cancer in young women (age ≤35).

INTRODUCTION Breast cancer in young women is a relatively rare disease; however it tends to be more aggressive and is the leading cause of cancer death in this population. The aim of this study is to investigate the clinical and biological features of breast cancer arising in young Turkish breast cancer patients. MATERIALS AND METHODS Patients with breast cancer aged 35 or less (≤35 years) were selected for the study. In total 211 cases were included. Pathologic features; histologic subtypes, grade, lymphovascular invasion, axillary involvement, and stage were recorded for each. RESULTS The most common subtype was luminal B (36.5%), followed by luminal A (30.8%), triple negative (23.2%) and HER2+(9.5%) subtypes. Twelve percent of the patients had stage 4, 32.7% had stage 3, 46.4% had stage 2, and 6.2% had stage 1 disease at the time of diagnosis. Mean tumour diameter was 3.87 cm (range 0.3-13 cm). The axillary lymph nodes were positive in 74.4% of the patients, while lympho-vascular invasion was seen in 56.4%. Some 9.5% of patients had grade 1, 51.2% had grade 2, and 31.8% had grade 3 tumors. CONCLUSIONS Young women with breast cancer in Turkey are more likely to present with luminal B subtype. Tumors in young women are more likely to present with advanced disease, to be high grade and and to have more lymphovascular invasion. Further research should focus on whether we need new treatment strategies for young patients with breast carcinoma.