Differences between male and female breast cancer. I. Epidemiological features.

The authors' interest was focused on the direct determination of differences between the salient features of breast cancer in men and women in a large number of patients. Various epidemiological features were analyzed in a group of 386 male and 21,491 female breast cancer patients registered in the Cancer Registry of the Republic of Croatia from 1968 until 1988. This was a population-based study, and all male and female breast cancer cases recorded during the mentioned period were included in the study. During this 21-year period, the total incidence rate of breast cancer in men was about 0.83/100,000, and the mortality 0.2,/100.000. In the same interval, in women the rates doubled from 30 to 60/100,000, and 13 to 29/100,000, respectively. The highest incidence rates were recorded in the 80-84 age group in men, and 60-64 age group in women. The mean age at diagnosis was 63.4 years in men and 58.2 years in women. The distribution in terms of TNM-stages in men was: stage I-10.10%; II-40.67%; III-32.40%; IV-16.83%; in women; I-12.19%; II-49.36%; III-27-58%; IV-10.86%. The results showed that breast cancer in men had epidemiological characteristics of a sporadic disease, occurring continuously at a specific mean frequency in the general population and being little affected by environmental impacts. Conversely, in women affected by the disease there was a tendency of continuous rise in the morbidity and mortality, which might have been due to the trigger action of one or more environmental factors.(ABSTRACT TRUNCATED AT 250 WORDS)