When was the last time you were scared to death? People over 50 or those with a history of colon or rectal cancer often avoid the type of medical screening that could save their lives because they're afraid.

And because colon cancer, in particular, has few if any symptoms until the disease is in more advanced stages, the fear of a colonoscopy makes it easy for people to postpone — or refuse altogether.

Dr. Brent Christensen, a surgeon at LDS Hospital, frequently sees the result of that fear. Yet if people who avoid the procedure would approach it like eating their vegetables ("do it because it's good for you"), tens of thousands of families could be spared the heartache of losing a loved one each year, he said.

Christensen will answer questions about colon and rectal cancer and treatment this Saturday for callers who participate in the monthly Deseret News/Intermountain Healthcare Hotline. From 10 a.m. to noon, he and LDS Hospital's chief of surgery, Dr. Kerry Fisher, will answer questions by phone. Call 801-236-6061 or 1-800-925-8177.

The American Cancer Society reported more than 148,000 people were diagnosed with colon cancer last year, and 49,400 people died as a result of the disease. Because it is slow-growing, those who succumb to it usually do so between two and five years after diagnosis, Christensen said.

"The screening numbers (with colonoscopy or other tests that can show a problem) are low. People are afraid," he said, noting a colonoscopy is recommended at age 50 for those without a family history of the disease.

"That's because the incidence (of colon cancer) peaks about age 65, and we want to start several years before that malignant lesion shows up."

Pre-cancerous lesions and polyps can be quite easily removed before they create a problem, adding to the incentive for early screening.

Patients with an immediate family member who has had colon cancer should be screened about 10 years younger than the family member was at diagnosis, he said.

Because early signs of colon cancer can be easily dismissed as minor problems, many people don't recognize them as a flag for something more serious, he said. Changes in bowel habits, thin stools, constipation or diarrhea and blood in the stool "tell us people have something to be concerned about, though they can signal a lot of other things."

Bright red blood in the stool indicates possible hemorrhoids or fissures in or near the rectum, while blood from an intestinal tumor is darker, old blood.

Those who are diagnosed with the cancer are categorized into stages, based on the severity of the disease.