Male Breast Cancer

Abstract

Thirty male patients with breast carcinoma were examined for sex chromatin. One of them was found to be sex chromatin positive. Chromosome analysis of peripheral blood revealed the chromosomal constitution normally found in the Klinefelter syndrome. By pooling series of cases of male breast cancer, in which systematical screening for sex chromatin was made, it was found that 9 out of 242 patients were sex chromatin positive, which is a higher number than that found in the normal male population. Calculated on the basis of the incidence of breast cancer in women and men, and of the incidence of sex chromatin positive individuals in the normal male population, the incidence of breast cancer among patients with the Klinefelter syndrome was found to be about one fifth of the incidence of breast cancer in women and about twenty times the incidence of breast cancer in normal men. The breast carcinoma found in the sex chromatin positive patient in our material presented no special histological features. Testicular histology showed a pattern different from that normally found in the Klinefelter syndrome, since no totally hyalinized a‐cellular tubules, which are considered pathognomonic for the Klinefelter syndrome, could be demonstrated.