Sigmoid Adenocarcinoma with Regional Scrotal Metastasis.

Colorectal cancer is a common disease, representing the third and second most common cause of cancer death in the United States in women and men, respectively. [Ahnen et al.: Mayo Clin Proc 2014;89: 216-224; Siegel et al.: CA Cancer J Clin 2016;66: 7]. It is estimated that 20% of patients have distant metastatic disease at time of diagnosis [Ahnen et al.: Mayo Clin Proc 2014;89: 216-224; Siegel et al.: CA Cancer J Clin 2016;66: 7]. The most common metastatic sites include regional lymph nodes, liver, lungs, and peritoneum via lymphatic/hematogenous dissemination as well as contiguous and transperitoneal routes [Ahnen et al.: Mayo Clin Proc 2014;89: 216-224; Siegel et al.: CA Cancer J Clin 2016;66: 7]. Upon review of the literature, we found that metastatic colon cancer to the scrotum is rare. The following case report proved to be a unique example of this type of metastasis. This rare regional metastasis is theorized to have resulted from a colo-urethro-scrotal fistula that precipitated from the patient's prior traumatic event.