Last Modified: July 6, 2003
Dear OncoLink "Ask The Experts,"
I would like to know the differences, signs and symptoms, that patients present with left sided, right- sided and sigmoid cancers.
Timothy C. Hoops, MD, Clinical Assistant Professor of Medicine in the Gastroenterology Division at the University of Pennsylvania and Director of Gastroenterology at Penn Medicine at Radnor, responds:
There are few differences in the clinical presentations of cancers in these different areas of the colon. There may be a slightly higher chance that cancers in the left and sigmoid colon may cause obstruction. Because they are closer to the end of the colon, if they bleed, the blood may be more visible because it has less time to mix with stool. Pain is usually not a symptom of cancer, but if the cancer had gone through the wall of the colon, or if it cause bowel obstruction, it might cause localized pain. Unfortunately, colon cancers are generally asymptomatic until they are quite far advanced. This is the main reason screening examinations, particularly with colonoscopy, can be so useful.