Black Men Have Higher Incidence Rates for All Types of Breast Cancer

Grantee: Hyuna Sung, PhD
Institution: 
American Cancer Society
Area of Focus: 
Surveillance and Health Equity Science

Research has shown that in the US, white women have slightly higher incidence rates of breast cancer than Black women. (Incidence rates describe the number of new cancer cases diagnosed each year , typically expressed per 100,000 people, for a described population.) But when breast cancer incidence rates are considered by subtypes, Black women have about 2 times higher incidence rates for triple negative breast cancer (an aggressive subtype with the fewest choices for treatment) and lower rates of hormone receptor (HR)-positive cancers, for which hormone therapy is a treatment option. It’s been unclear whether there are similar racial differences in men with breast cancer.

ACS researchers recently published a study, led by Hyuna Sung, PhD, that found the breast cancer incidence rates were 52% higher in Black men than white men. In fact, Black men had considerably higher incidence rates for all breast cancer subtypes defined by HR/HER2 status compared with white men. The higher risk for these cancers persisted across all age groups of Black men.

The reasons for the elevated risk of breast cancer among Black men are not known, but the researchers said they reflect differences in the prevalence of risk factors across populations. Risk factors for male breast cancers are largely unknown, but some known risk factors are:

  • A family history of breast or ovarian cancers
  • Mutations in the BRCA2 gene
  • Radiation exposure
  • Conditions that change the balance of hormones, such as Klinefelter syndrome and gynecomastia
  • Certain lifestyle risk factors such as heavy drinking (of alcoholic beverages) and obesity

It’s not known how these risk factors related to specific subtypes. Further studies are required to inform prevention strategies for men.

Why Does it Matter? This is the first study that examined subtype-specific breast cancer incidence rates among men and found dissimilar patterns as those among women.