DEAR DR. DONOHUE: I’m writing to alert your readers to malignant melanoma. I lost my husband to it last year. He had what looked like a mole, but it was growing. I was concerned and begged him to see a doctor. He put it off. Finally, he did see a dermatologist, but by that time, it had spread throughout his body. I am left to raise three children. He was 49. People need to be aware of this cancer. – R.R.

ANSWER: Melanoma is the most dangerous skin cancer, but when caught in its early stages, it can be curable. It’s the fifth most common male cancer and the sixth most common female cancer. One in 63 Americans will develop it, and the cancer arises most often in the late 40s and in the 50s.

Although melanomas can arise in skin not exposed to the sun, the sun’s ultraviolet rays are a major risk for developing this cancer. It’s not so much cumulative life exposure to sun, but intense, early-life exposure that caused sunburn. Blue-and green-eyed people, blondes and redheads are more apt to develop melanoma. People with large numbers of moles – more than 50 – are also at risk, as are people with a family history of melanoma.

Distinguishing a mole from a melanoma can be tricky and, if a person is in doubt, a doctor should make the call. In contrast to a mole, melanomas are not symmetrical. If, in your mind, you fold one in half, the two halves don’t correspond. Melanomas have irregular borders. They might have one predominant color – brown or black – but mixed in are blues and reds. Most melanomas are larger than a pencil eraser. Melanomas enlarge and are usually elevated above the skin surface.

Everyone should be on guard for this cancer. Any suspicious skin patch ought to bring a person to the doctor for an official interpretation.

I am terribly sorry to learn of your husband’s untimely death.

DEAR DR. DONOHUE: When a person is put on life support, does that mean he is not going to recover, or does he have a chance of living? My boyfriend always told me not to put him on life support. He was put on it but was taken off when I told the doctors he did not want it. He got well. One month later, he had a heart attack, and they put him on life support again. I told them again of his wishes. They took him off, and he died four hours later. I have felt guilty about this. – M.B.

ANSWER: Life support – the prolongation of life through the assistance of breathing machines and medicines – is intended for people whose prospects for recovery and independent living are good. It is not possible in every instance to make the determination of a person’s recovery, so there are times when people with incurable, untreatable illnesses are put on life support. If evidence accumulates and points to a hopeless outlook, life support should be terminated. Your boyfriend’s wishes were definite. He did not want life-support assistance in the face of little hope for recovery. You respected his wishes. You should not feel guilty. If the odds had been in his favor, the doctors would have told you that.

DEAR DR. DONOHUE: I read your item on Flomax for treatment of an enlarged prostate gland. Flomax does make urination easier. However, a cautionary note is in order. In fact, Flomax TV ads now end with this: “If considering eye surgery, tell your eye surgeon you have taken Flomax.”

I used Flomax sometime before I had cataract surgery, but its aftereffects complicated the operation. My iris lost its response to medicine, and I had to have follow-up surgery. So far, everything is all right. We’ll see. – H.N.

ANSWER: Flomax enhances bladder-emptying by blocking nerve signals to muscles in the prostate gland and at the bladder outlet that are contracting and preventing urine passage. In cataract surgery, the doctor instills eyedrops that enlarge the pupil to facilitate removal of the clouded eye lens behind the pupil. Men who are taking or have taken Flomax can have a pupil that doesn’t respond to those drops. The pupil narrows during the surgery. The condition is called IFIS – intraoperative floppy iris syndrome. You’re right; patients should tell their doctors about their current or past treatment with Flomax.

DEAR DR. DONOHUE: I am 77 and have taken Toprol-XL for five years. Last year my blood sugar was raised — 6.2, 6.3. When it reached 6.4, my doctor sent me to an endocrinologist, who had me see a dietitian. I follow the diet, but not too strictly. I check my blood sugar twice a day, and it’s always normal. My last fasting blood sugar was 100. Could the Toprol have raised my blood sugar? I read that it can. — D.K.

ANSWER: The numbers you cite are values for hemoglobin A1c. Hemoglobin is a large protein inside red blood cells. It holds onto oxygen for transport. Sugar also sticks to hemoglobin, and that’s the hemoglobin A1c. It provides an average blood sugar reading for the prior three to four months. Your numbers aren’t bad. Your fasting plasma glucose value of 100 (5.5) is normal. You should still follow your diet, but you don’t have to make a switch in medicines unless your doctor tells you to. Things are fine.

Toprol is a beta-blocker medicine, and one of its uses is blood pressure control. It can influence diabetes in two ways: It blunts the symptoms of low blood sugar — a fast heart rate and sweating. Diabetics develop low blood sugar by taking too much medicine, eating too little food or exercising too strenuously without compensating for it with an added intake of carbohydrates. Beta blockers also can produce an increase in blood sugar, but they rarely do so.

An epidemic of diabetes is occurring in North America. Readers who would like more information on diabetes can order the booklet on it by writing: Dr. Donohue – No. 402, Box 536475, Orlando, FL 32853-6475. Enclose a check or money order (no cash) for $4.75 U.S./$6 Can. with the recipient’s printed name and address. Please allow four weeks for delivery.

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 www.rbmamall.com