Breast Cancer May Be Biologically Different in Men Than in Women

The approach to treating breast cancer in men is largely the same as in women. However, large studies of treatments for men have been hard to come by, as the number of male breast cancer patients is small, even in large referral centers.

To compare outcomes between men and women with breast cancer, investigators conducted a retrospective cohort study involving 16,000 men (median age, 63.3 years) and 1.8 million women (median age, 59.9 years) in the National Cancer Database who were diagnosed with breast cancer from 2004 through 2014. Race, ethnicity, clinical characteristics, treatment, and accessibility to care were taken into account.

At median follow-up of 54.0 months for men and 60.5 months for women, overall survival (the primary outcome) was significantly worse for men than for women (45.8% vs. 60.4%); also worse were 3-year survival (86.4% vs. 91.7%) and 5-year survival (77.6% vs. 86.4%). Even after controlling for multiple factors, 3-year mortality was 15% higher in men than in women. A striking finding was that survival was inferior in men particularly early after diagnosis. As in other reports, males were typically older than women at presentation and were more likely to have higher-stage disease and be undertreated, regardless of stage. They were also more likely to have Recurrence Scores that were very high (≥31) or very low (≤11).