Concerning a familial association between breast cancer and both prostatic and uterine malignancies

The mammary gland is one part of an integrated genital organ system. The various parts of this system have distinctive shared biological and pathologic characteristics. Because of the frequent association of mammary, uterine, and ovarian cancer in the same individual, it is hypothesized that some common etiologic factor exists which might also have a familial expression in other parts of this genital organ system. Based upon this, the familial incidence and distribution of all malignancies for a group of 145 breast cancer patients were determined and compared to that of 139 randomized control patients. Significantly higher incidences of only uterine, prostatic, and breast cancer were found among both maternal and paternal relatives of the breast cancer patients.