DEAR DR. DONOHUE: I examined myself and found a lump on one testicle. I will have it checked soon. I have studied the Internet and found no other causes for such lumps but cancer. I have no discomfort, and the lump is pea- to bean-sized. Are there possibilities other than cancer? – S.D.

ANSWER: How old are you? Testicular cancer is mostly a young man’s cancer, with the peak ages for it occurring between 20 and 40. Past age 50, the majority of cancerous testicular lumps are a different kind of cancer – lymphoma.

Testicular cancer usually starts out as a painless lump. It can also cause testicle hardening or swelling.

You have done the smart thing. You have arranged to have your lump checked by your doctor. All men with such a lump ought to do the same, and they should examine their testicles monthly. When caught early, this cancer is highly treatable and often curable.

Not all testicular lumps are cancer. Harmless cysts create lumps. So do inflammations of the epididymis. The epididymis is a large, C-shaped structure on top of and curving over to the backside of the testicle. It is a long, coiled duct where sperm is stored and where it matures.

DEAR DR. DONOHUE: I have recently been diagnosed with chronic lymphocytic leukemia. I am a man, 84 years old and in excellent physical condition. I exercise every day, am 5 feet 9 inches tall and weight 160 pounds. What is my ultimate prognosis? How fast does this disease progress? What is the treatment? – E.H.

ANSWER: Leukemia is cancer of white blood cells. Lymphocytes are one kind of white blood cell. “Chronic” usually implies that the leukemia does not progress rapidly.

Chronic lymphocytic leukemia – CLL – is the most common kind of adult leukemia. “Leukemia” and “cancer” are words that send chills down everyone’s spine. Not all cancers are death sentences. CLL is an example of one that usually is not lethal.

The outlook for it depends on its stage. In stage 1, the cancer is found only in blood and bone marrow. This stage, a common one for CLL patients, has a good prognosis. Stage 1 patients, on average, survive at least 10 years, and treatment is not given until the patient has become symptomatic or until signs of spread are evident.

In stage 2, lymph nodes and the spleen enlarge. Even at this stage, the outlook is not bad. The average life expectancy here is seven or more years.

Stage 3 has a less rosy prognosis. Here, the bone marrow stops making blood cells. The average survival of stage 3 patients drops to 1.5 years.

When and if treatment becomes necessary, one of two chemotherapy drugs is usually chosen – chlorambucil or fludarabine. Sometimes the cortisone drug prednisone is added to the regimen.

DEAR DR. DONOHUE: Do you have any information on head lice? My daughter’s children are full of them. – R.G.

ANSWER: Children usually introduce head lice into the home from contact with a classmate. Lice are no reflection on a family’s cleanliness or housekeeping fastidiousness. The fact that there are up to 12 million cases of head lice yearly in the United States gives you an idea of how widespread the infestation is.

Neither your daughter nor you have to panic. There are many effective lice killers. RID shampoo is a popular one. It has to be applied twice. The second application is given seven to 10 days after the first. Nix lotion or cream is another reliable treatment. Ovide (which is not for infants) is applied to dry hair for eight to 12 hours. Both Nix and Ovide need a second application in a week or so. Explicit directions come with every product and must be followed to the letter.

Many advise, after treatment with one of the above products, to comb the child’s hair with a fine-toothed comb to dislodge nits that cling to strands of hair. The hair should first be rinsed with a solution of half-vinegar and half-water, and the comb should be dipped into straight vinegar. Nits are lice eggs.

DEAR DR. DONOHUE: I have genital herpes. Can a person like me spread the virus through seminal fluid? I never have sex during an outbreak, and I take medicine to keep the virus in check. Could I possibly catch the herpesvirus a second time from another person? Will a cure ever be found? – B.J.

ANSWER: Herpesvirus-2 is the cause of genital herpes. It, like herpesvirus-1, is a lifelong infection. The major route of transmission is skin-to-skin contact. It can also be passed in genital secretions like seminal fluid.

Herpesvirus-2 can also be spread when there is no visible outbreak of the virus. It is spread less often at those times, and condom use decreases the likelihood of transmission during those periods. People with a visible outbreak should not have sexual relations even with a condom.

Infection provides some immunity against acquiring a new infection. There is always a chance of acquiring a new one, but the chance is not as great as it is for a person who has never been infected with the virus.

I believe there will be a cure. When? I don’t know.

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.