Survival in familial breast cancer patients.

This study was conducted to measure survival in breast cancer patients differing in their familiarity of the disease. A total of 556 familial patients and 4551 general patients were evaluated. Survival was higher with bilateral than unilateral disease in both groups of patients. This difference was observed only when survival was measured from the first primary; it disappeared when survival was measured from the second primary. Three groups of familial patients, who likely differed in genetic risk, had similar survival curves. They were also similar to a general series patients when stage of disease was controlled and the comparison involved primarily unilateral patients. Previous reports of increased survival in familial and bilateral patients were thus not confirmed. The previous results were likely the consequence of bias arising from measuring survival from the first primary. Survival does not appear to be influenced by family history or laterality of breast cancer.