DEAR DR. DONOHUE: Do moles become cancer? I have a few, and my wife is after me to see a dermatologist about them. I have had them for years, and they have not changed one bit. Do I need to be in a hurry to see a doctor? – R.P.

The subject of moles is a touchy one. No one wants to dismiss them and then have one turn out to be a melanoma, the deadliest kind of skin cancer. On the other hand, no one wants to send the entire population to a doctor when it isn’t necessary. Let me give you some mole facts that can help you come to a decision.

Just about everyone has one or more moles. A mole is a cluster of cells that contain the pigment melanin. Melanin accounts for the mole’s brown to black color. How to tell a mole from a melanoma is not always an easy chore for a layperson and often not even for a doctor, but here are some guidelines:

Moles are usually smaller than the eraser on the end of a pencil.

Moles tend to have a uniform color, all brown or all black. Melanomas often are brown, black or slate gray, often with hues of white, red or blue intermixed.

A mole has a uniform shape. In your mind’s eye, you can fold it in half and both halves are the same shape. Melanomas do not have that kind of symmetry.

The border of a mole is smooth and regular. The border of a melanoma is jagged.

Any suspicious spot that enlarges or changes colors sends out a cancer signal and must be examined by a doctor without delay. Any spot that becomes a sore, crusts, scales or oozes is another signal for immediate attention.

Doctors have a more practiced eye to discriminate between the two. They have lenses that help them make the distinction. And when the call is close, they can biopsy the dark blotch for microscopic examination. You don’t have to hurry, but if in doubt see a doctor.

DEAR DR. DONOHUE: Shortly after my first grandson was born, he had trouble keeping milk down. Things got worse, and he began to vomit after every feeding. The doctor made a diagnosis of pyloric stenosis. He had an operation. I would like to know if he will be troubled by it in the future. – R.M.

The pylorus is the narrow tunnel at the end of the stomach through which partially digested food passes into the small intestine. A band of muscle, the sphincter (SFINK-tur), encircles the pylorus and keeps it shut until the stomach is ready to send food on to the intestine.

Pyloric stenosis is a narrowing of the tunnel due to a greatly enlarged sphincter muscle. Food cannot exit the stomach. The baby throws it up. The description of classic pyloric stenosis vomiting is projectile, like a jet of water from a hose. Most babies have not read the classic description, and they throw up less dramatically. Often the vomiting does not begin until the fourth week of life, and sometimes not until the fourth or fifth month.

Surgery brings a cure. The doctor incises the overgrown muscle, and that relaxes the sphincter so food can move easily from stomach to intestine. The results are rapid. Many babies are eating normally the day after surgery.

You might have to buy sunglasses for your grandson. His future is that bright.

DEAR DR. DONOHUE: I take calcium for osteoporosis. Does it matter when I take it? I usually do so after breakfast. – N.C.

Calcium is better absorbed when the stomach has a full supply of stomach acid. It is best, therefore, to take it with or immediately after meals.

Don’t take more than 500 mg of calcium at one time. If your total daily dose is 1,500 mg, then take a 500-mg tablet with or after each meal.

DEAR DR. DONOHUE: A fellow worker told me she had mumps of the ovary. Is there such a thing? This person tends to exaggerate. – B.C.

The mumps virus can infect the ovaries as well as the testicles. Ovarian infection is not common. Its symptoms include pain low in the abdomen, nausea, vomiting and fever. It does not usually affect a woman’s fertility.

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.

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