"Synchronous cancers "

" Synchronous CRCs, defined as two or more distinct primary tumors separated by normal bowel and not due to direct extension or metastasis, occur in 3 to 5 percent of patients with colon cancer [26, 27]. The incidence is somewhat lower (about 2.5 percent) when patients with hereditary nonpolyposis colorectal cancer (see below) are excluded [28]. Synchronous primaries have the same prognosis as solitary malignancies when the highest stage of disease is compared [27]."