DEAR DR. DONOHUE: For more than three months, I have had a lump in my neck that hurts only if I press on it hard. I’m not sure if it has gotten any bigger, but it’s beginning to worry me. What do you think it might be? If it makes any difference, I am a 32-year-old male. – S.K.

ANSWER: The lump you feel is probably a lymph node. We have hundreds of them scattered throughout the body. They’re filters of germs and other foreign materials. They constitute an important defense against the spread of infection in the body.

An enlarged node can represent serious or harmless conditions. Size helps distinguish between them. Nodes smaller than .4 inches in length and width (1 cm by 1 cm) are more often indications of benign enlargements, like transient infections. Sore throats always cause neck lymph nodes to get bigger, and those nodes are most often tender when they’re pressed. Dental infections are another cause of such nodes. Once the infection leaves, the nodes shrink.

The most serious cause of big lymph nodes that cannot be ignored is cancer. The cancer can be a cancer of the nodes themselves (lymphoma or Hodgkin’s disease), or it can be a cancer that has spread to the nodes from some other site. Cancerous nodes are large, firm or rubbery, and usually not tender.

The fact that you have no symptoms is reassuring. However, a large node is something whose cause has to be found, and the cause can usually be found without too great trouble. If it cannot, then the node is removed for microscopic examination.

You must see your doctor soon. This is a question that demands an answer.

DEAR DR. DONOHUE: My husband is 25. He drinks a six-pack of beer every night, and more on weekends. I admit he never appears to be drunk, never stumbles and is always reasonable, but I think this amount of alcohol cannot be good for him. What could drinking this much alcohol do to him? – P.K.

ANSWER: A six-pack of beer every day is way too much alcohol. The probability of coming down with liver cirrhosis looms over anyone who drinks this volume of beer. Cirrhosis means the liver becomes so scarred that it cannot perform its many functions. Dying from liver cirrhosis is not a pleasant way to die. Ten to 15 years of drinking this much alcohol makes him a likely candidate for cirrhosis.

The fact that a six-pack has little to no effect on your husband is not a particularly good sign. It implies that he has developed a tolerance for alcohol, and that comes only from drinking large amounts for long periods. It’s a sign of alcoholism.

DEAR DR. DONOHUE: Several years ago, I was given a diagnosis of pernicious anemia. I had been taking monthly B-12 injections. My doctor moved away. My new doctor had me take a B-12 test the day after I had an injection. The test came back showing a high level of B-12, and I was told to stop taking the injections. I am confused. I think my doctor is confused too. Getting a test the day after an injection is bound to show a high level. What do you think? – S.D.

ANSWER: Your position is reasonable. The B-12 blood level is going to be high the day after getting a shot of it.

If you haven’t had any B-12 for a few months, have the test redone. If you need the vitamin, the test will show that.

If you are still taking B-12, the only way to determine if you really need it is to skip a couple of months and then get the test done. Two months of not taking the shot won’t hurt you.

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 at P.O. Box 536475, Orlando, FL 32853-6475.

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