Incidence of Male Breast Cancer in California, 1988–2000: Racial/Ethnic Variation in 1759 Men

Abstract

Breast cancer among males is rare, accounting for less than 1% of all breast cancers in the United States. Although it is rare, it can cause significant morbidity and mortality. We analyzed data from 1759 California males whose diagnosis of breast cancer was made between 1988 and 2000 and reported to the population-based California Cancer Registry. Cases were primary, microscopically confirmed in situ and invasive breast cancer. Age-adjusted incidence rates per 100,000 men were highest in Blacks (1.65), intermediate in whites (1.31) and lowest in Hispanics and Asian/Pacific Islanders (0.68, 0.66, respectively). Age at diagnosis differed by race (p = 0.001) with blacks diagnosed at an earlier age than whites or Asians/Pacific Islanders. Stage at diagnosis also differed by race (p = 0.001) with blacks more likely to be diagnosed at distant stage. Further investigation showed that blacks and Hispanics were more likely to be diagnosed with tumors 5 cm in diameter or greater. The proportion of men having surgery following a diagnosis of breast cancer also varied by race/ethnicity (p = 0.001) with blacks least likely to have surgery following diagnosis. Understanding racial/ethnic variation in male breast cancer may provide clinical and etiologic implications for breast cancer in different populations.