HER 2-positive Luminal B breast cancer according to the clinicopathological features : a population-based study from SEER program

This is the population-based study to analyze the prognostic value of the clinicopathological features in HER2-positive Luminal B-subtype breast cancer. Using the 2010-2012 Surveillance, Epidemiology, and End Results Program (SEER) data, a retrospective, population-based cohort study to investigate the clinicopathological features in the overall survival (OS) and breast cancer-specific mortality (BCSM) in HER2-positive Luminal B subtype. Different characteristics, overall survival, breast cancer-specific mortality were compared. There were 16,662 patients with breast cancer (141 male; 16,521 female). Compared with females, males were more likely to be older, black (each P < 0.01). Male patients also showed lower grade, more advanced stages, larger tumor size and more lymph nodes metastasis (each P < 0.05). Males also were less likely to receive radiation compared with females (P < 0.01). Univariate analysis showed that a general decrease in OS in those patients who presented with age ≥ 50 years, black, male, more advanced stage and bilateral sides at diagnosis, had lower grade, larger size, more lymph nodes and distant metastasis, and those who did not receive radiation. In contrast, multivariate Cox analyses confirmed the independent prognostic significance of age at diagnosis, stage, tumor size and distant metastasis. Sex did not reach significance with this test. The similar results also performed in BCSM. We observed significant differences in patient characteristics according to age at diagnosis and race. In addition to tumor stage, tumor size and distant metastasis had clear influence on OS and BCSM in HER2-positive Luminal B.