Clinicopathological Features and Metastatic Pattern of Triple-positive Breast Cancer Among Female Patients at a Tertiary Care Hospital.

Objectives The heterogenicity of breast cancer (BC) is determined by the status of human epidermal growth factor receptor 2 (HER2/neu), estrogen receptor (ER), and progesterone receptor (PR). Triple-positive BC (TPBC) expresses the amplification/overexpression of the HER2 pathway and is positive for ER and PR. This subtype has a distinct clinical behavior. However, very few studies are focused on TPBC. This study investigated the clinicopathological features and metastatic pattern of TPBC. Methods A seven-year retrospective study was conducted at King Abdulaziz University Hospital in Jeddah, Kingdom of Saudi Arabia. All females with TPBC diagnosed between January 1, 2010, and June 30, 2017, were enrolled. Mean and standard deviation were calculated. Results From 1205 BC patients, the TPBC incidence was 10% (n = 124). The mean age at diagnosis was 51 years. On physical examination, a high tendency to show pathological skin changes was observed. Invasive ductal carcinoma was the most common histological type, presenting with a poorly differentiated histological grade (grade 3). Over a median two-year follow-up, the incidence of metastasis was 27.4% (n = 34). Bone was the most common site. The incidence of locoregional recurrence was 9.7%. Overall survival was 89.5%. Conclusion TPBC has an early tendency for metastasis and commonly affects the breast skin. BC should be approached based on the immunohistochemical diagnosis. We encourage more comprehensive studies to target TPBC for more insights into the heterogeneity of BC.