Colon Cancer: The Inside Story While Fidel Castro recuperates from intestinal surgery, some doctors speculate that the Cuban leader might have colon cancer. According to the WHO, cancer is the second leading cause of death in Cuba, and the colon is a frequent cancer site. In the United States, colon cancer takes over 50,000 lives each year, making it the second highest contributor to cancer-linked mortality. Early detection may be tantamount to survival: diagnostic techniques, such as colonoscopy and CT colonography (virtual colonoscopy), can be used to locate precancerous polyps and immature tumors before it’s too late.