Development of breast cancer in a 21-year-old childhood Wilms' tumor survivor with a BRCA1 2634delC mutation.

Breast cancer at age 21 is rare, even in individuals who have a genetic predisposition. These early diagnoses are usually the result of a hereditary cancer syndrome. Other contributing factors, such as chemotherapy and radiation for previous malignancies, can also increase the risk of secondary malignancies, including breast cancer. Here we present one of the youngest cases of breast cancer reported in the literature: a 21-year-old Wilms' tumor survivor (diagnosed at age 6), who was found to have a familial BRCA1 mutation and was diagnosed with ductal carcinoma in situ at age 21.