Is There a Survival Difference Between Male and Female Breast Cancer Subtypes According to the Prognostic Staging System? A Population-Based Cohort Study

Abstract

Background In retrospective studies investigating the difference in survival by gender, there are conflicting results. It was aimed to compare overall survival (OS) and breast cancer-specific survival (BCSS) in male and female breast cancer subtypes according to the prognostic staging system. Methods Overall survival rates and BCSS rates of patients diagnosed with breast cancer between 2010 and 2019 compared by gender for all cohorts, stages, and molecular subtypes using the SEER Database. The stage has been rearranged according to the eighth edition of the AJCC. Results 364 039 patients were included in the study. .7% (n = 2503) of all breast cancers were male breast cancer. Overall survival (male: 5-year OS 73.9%, female = 5-year OS 86%) and BCSS rates (male: 5-year BCSS 78.9%, female = 5-year BCSS 94.7%) were significantly higher in females than in males for all cohorts. OS (male: 5-year OS 66.2% vs female: 5-year OS 88.3%), and BCSS (male: 5-year BCSS 88.4% vs female: 5-year 93.6%) rates were higher in hormone receptor (HR)-positive/Her2-negative female patients. Overall survival rate is higher in females in stage I (male: 5-year OS 81.5%, female: 5-year OS 92.8%), and BCSS rate is higher in stage I (male: 5-year BCSS 94.8%, female: 5-year BCSS 97.5%). Males have 2 times (HR = 2.023) higher overall mortality risk than females, but the risk of dying from breast cancer is only 1.6 times (HR = 1.596) higher. Conclusions Breast cancer-specific mortality is significantly higher in male breast cancers, especially in the early stage, and HR-positive subtype than females.