Dear Dr. Roach: A year ago, I had surgery for bladder cancer, and had a small stroke and pulmonary clot. During this past year, Ive had five CT scans, three chest X-rays and a couple of other scans to diagnose the stroke and clot. I also had some kind of scan in radiology to put in and then take out an IV blood filter. I am having another CT scan to check kidney function and another chest X-ray in May. Now my GP says Im due for a mammogram. How much is too much radiation? I know its cumulative. R.W.
Answer: People get nervous about radiation. Fear of radiation can be rational or irrational. The irrational part is nonetheless very human: There is something fundamentally terrifying about a force you cant see or sense in any way but that can cause terrible damage. Especially for those of us who grew up worried about atomic bombs and atomic testing, radiation is disturbing on a deep level.
There also are rational reasons to be concerned about excess medical radiation. Six CT scans in a year is a lot (the blood filter was most likely placed with ultrasound, which uses sound waves, not X-rays). It is reasonable to question the necessity for any additional X-rays.
Fortunately, the amount of radiation in a mammogram is very small. The amount of radiation in a CT scan is roughly 20 times the amount in a mammogram. If you are between 50 and 74, the benefits of mammogram screening almost certainly outweigh the risks of the radiation.
Dear Dr. Roach: Fifteen years ago, I had a successful brachytherapy treatment for prostate cancer. Subsequent annual PSA results indicate minimal levels. I am 82 years old and in otherwise excellent condition, and generally very active. However, in the past few years I have had periods of considerable fatigue. My blood counts are within the normal range, but my testosterone is at a very low level. My family physician counsels against testosterone therapy because of the possibility of reigniting prostate cancer. This seems to be based on a long history of a causal relationship.
A senior fitness trainer at my squash club argues that quality of life is important, so I should try testosterone therapy and then watch my PSA levels carefully. He says this because there have been a number of more recent trials in which there seemed to be a changing view that there is no definite connection that testosterone therapy causes new cancer. He has several clients who have found renewed energy from testosterone therapy. I have reviewed endless articles on the topic, but find nothing definitive. This may be different for males who have not had a previous history of prostate cancer. Whats your opinion? The fatigue is troublesome, and I would like to try testosterone but not at a real risk of setting myself back 15 years. R.T.
Answer: I am glad your prostate cancer seems to be in remission. Brachytherapy is the use of implanted radiation seeds or pellets to destroy prostate cancer cells.
I cant recommend a course of action that your own physician has counseled against, as he or she may have more information about you than I do.
The reason you arent finding any definitive articles is that there are no well-done scientific studies looking at people with a history of prostate cancer being treated with testosterone. There are some data, however. A 2013 review looked at seven studies with a total of about 200 men with a history of prostate cancer treated with testosterone. Only one had an increase in PSA level suggesting recurrence; most men were able to get normal testosterone levels, and most but not all had improvement in symptoms. Fatigue is a common symptom in men with low testosterone but is not specific for low testosterone. Many conditions can be associated with fatigue.
My own practice, in consultation with the patients urologist, is to consider a trial of testosterone replacement in men who are thought to be cured of prostate cancer based on very low or nondetectable PSA levels, who have symptoms (and often physical exam findings) that are very consistent with low testosterone and who have a low level on laboratory testing. I agree that PSA levels (along with a history and physical exam) should be checked carefully.
Ultimately, it is a balance of risks. If the symptoms are bad enough to be worth a small risk of cancer recurrence, and for a patient who is able to weigh those risks himself and chooses to, I have cautiously prescribed testosterone.
