DEAR DR. DONOHUE: When I was in my 50s, I had a uterine fibroid about the size of a small grapefruit. One doctor said to leave it alone because it would eventually disappear. Another opinion was to have a hysterectomy. I chose to leave it alone, and it did disappear. Three years ago I had uterine cancer. Fortunately, it was detected early, and I have made a recovery. Did my not having the fibroid removed lead to the cancer? – F.S.

ANSWER: Uterine cancer is usually a cancer of the uterine lining, the endometrium. It also goes by the name of endometrial cancer. More than 36,000 new cases of uterine cancer occur yearly in North America. Most women come down with it after menopause.

Factors that influence the development of uterine cancer include high blood pressure, diabetes, menstrual periods that began early, menopause that occurred late, not having children, and obesity. The obesity link is interesting. Fat converts the small amount of male hormone made by women into the female hormone estrogen. Constant bombardment of the uterus by estrogen can stimulate cancer there.

Fibroids are not on the list of uterine cancer risks. Many women choose to ignore fibroids when they cause no symptoms or when the woman is on the brink of menopause. Fibroids almost invariable shrink after menopause.

A very small number of fibroids become cancerous. Those cancers are leiomyosarcomas, a word unfamiliar to the public because of its rarity. Not having your fibroid removed did not contribute anything to your uterine cancer.

The fibroid and hysterectomy stories are told in the pamphlet of that name. Readers can obtain a copy by writing: Dr. Donohue – No. 1106, Box 536475, Orlando, FL 32853-6475. Enclose a check or money order (no cash) for $4.50 U.S./$6.50 Can. with the recipient’s printed name and address. Please allow four weeks for delivery.

DEAR DR. DONOHUE: I am 79, and I have arthritis in my knees. The family doctor wants me to consider surgery for my knees. I don’t want to baby artificial knees, and I don’t want to be laid up for a long time after surgery. Is this unreasonable? How long do artificial knees last? – C.Z.

ANSWER: If the arthritis is sidelining you or if it causes you chronic pain, then you ought to consider the benefits of artificial knee joints. The people I know who have had this operation sing its praises. They are able to navigate easily and without pain after the operation.

You won’t be laid up for any long period of time after the operation. You start using the knees the day after surgery. For the first six to 12 weeks postoperatively, you avoid bending, squatting and stooping. You also participate in a physical therapy program that restores muscle strength lost from the inactivity of arthritis.

In short order, you can do just about anything you want. You can golf, swim, play doubles tennis and do just about all the activities that other 79-year-olds do.

Artificial knees last 20 to 25 years.

DEAR DR. DONOHUE: Several months back you had an article concerning a web on the inside of the eye. Since that article, my mother has developed it, and I cannot find out what it is. Would you repeat the information? – P.S.

ANSWER: A dirty-yellow web of tissue can grow on the white of the eye, usually on the nose side. It is called a pinguecula (ping-KWECK-you-lah). It comes from a lifetime of sun, wind and dust exposure, so people who work outdoors are the ones who most frequently come down with this.

If the web extends onto the cornea – the central, clear, dome-shaped covering over the pupil and iris – it is then called a pterygium (tuh-RIDGE-ee-um). If it interferes with sight, it can be removed. If it doesn’t, it is left alone, as is a pinguecula. Make sure a doctor confirms your suspicion.

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.