Sporadic breast, ovarian, or uterine cancers as risk factors for colorectal cancer

Sporadic colorectal, breast, endometrial, and ovarian cancers are common human malignancies. Not surprisingly, epidemiologic studies have identified multiple shared risk factors, including obesity, low exercise levels, and possibly hormonal (particularly estrogen) modulation. In addition, unlike hereditary nonpolyposis colorectal cancer syndrome, in which colorectal, endometrial, and ovarian cancers may occur because of a germline mutation in important mismatch repair genes, sporadic versions of these cancers may develop because of shared epigenetic alterations. These changes may be useful predictors of clinical outcome and response to disease-specific therapies.