DEAR DR. DONOHUE: I need information on colon polyps, colon cancer and colonoscopies. I just had my first colonoscopy. The doctor removed a polyp, and I have enclosed a copy of the pathology report. The doctor says I don’t need another for 10 years. My brother just had a colonoscopy, and he also had a polyp removed. His doctor told him to have another in three years. Why the difference between us? Should I have another sooner? – R.W.

You’re a first – someone who would like a colonoscope exam sooner than the doctor suggests.

Every year in the United States there are slightly fewer than 150,000 cases of colon cancer diagnosed, and about 56,000 people die from it. Just about all colon cancers arise from a polyp. Polyps (nose, vocal cord or colon) are growths from the surface of a structure. They’re very tiny at first and reach grape size in a number of years. Not all polyps are a prelude to cancer. But all colon polyps of a certain size have to be examined microscopically to see if they are the sort that turns into cancer.

The kind of colon polyp that turns into cancer is an adenoma (adenomatous polyp). Your polyp’s microscopic features revealed it to be a hyperplastic polyp, one that doesn’t become cancer. Your brother’s polyp was probably an adenoma, the kind that becomes cancer.

If a colonoscopy shows no polyps or no precancerous polyps, the usual interval to a follow-up exam is 10 years. On the other hand, if a polyp is an adenoma and if it’s larger than 0.4 inch (1 cm), then a follow-up exam is most often scheduled for three years. Three small polyps also require an early repeat colonoscopic examination.

DEAR DR. DONOHUE: Can you tell me in one sentence what triglycerides are? – T.S.

They’re fats. (That’s a short one sentence.)

At one time, doctors ignored triglycerides. Now these fats get the respect they deserve. They’re probably involved in artery hardening, heart attacks and strokes. They’re definitely involved in a newly described illness called the metabolic syndrome, something that contributes to heart attacks.

A normal triglyceride level is less than 150 mg/dL (1.7 mmol/L), and a high reading is greater than 200 (2.3). For an accurate triglyceride test, people have to fast for 9 to 12 hours before having blood drawn.

DEAR DR. DONOHUE: What are the signs of manic-depression? I think someone who works with me has it. I have read some things about it, but it’s not clear to me how it affects a person’s life. Are people who have it always hospitalized? – W.M.

Manic-depression (bipolar disease) is a roller-coaster of mood. In the manic phase, people demonstrate extraordinary amounts of energy. They can stay up late with little to no sleep. They are talkative and are perpetually on the go. They make grandiose plans and often try to carry them out. At times, they might hallucinate – see things that are not there and hear voices no one else hears.

The manic phase is followed by a depression so gloomy that people withdraw from interacting with others. They become immobilized with gloom. They have little energy to do the basic things of life. They feel hopeless.

People with manic-depression need hospitalization only when they are out of touch with the real world, which is only a small fraction of the time. Many go through life without ever having to be in a hospital.

Medicines can usually restore brain chemistry and bring manic-depressives to a state where they are not going through extreme mood changes. Lithium is one of the drugs commonly used for this disorder.

Dr. Donohue regrets that he is unable to answer individual letters, but he will incorporate them in his column whenever possible. Readers may write him or request an order form of available health newsletters at P.O. Box 536475, Orlando, FL 32853-6475. Readers may also order health newsletters from

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