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Until very recently, the use of testosterone (T) was prohibited in men with a prior history of prostate cancer, or even in men with just suspicion of prostate cancer. Yet a case I had this week underscores how dramatically ideas can change in medicine over a very short period of time.
About 6 months ago I saw Sam (not his real name) in my office, a 57 year old man, accompanied by his wife. He had undergone a radical prostatectomy for prostate cancer in 2004, and the blood test to monitor prostate cancer, called PSA, was undetectable, meaning that there was no evidence of any residual cancer cells in his body. The reason to see me was that he had absolutely no desire to have sex, even though the equipment was working. Also, his wife added, her husband seemed constantly tired, napping at all hours of the day. "I've never seen him like this," she said, indicating that he had always been a go-go-go kind of guy. He denied being depressed.
"I just don't feel like doing anything," he said, "sexually or otherwise."
Blood tests revealed low levels of testosterone. After discussion of the risks and possible benefits, Sam elected to try T therapy. I started him on T gel, applied daily, and subsequent blood tests confirmed good T concentrations in the blood.
At his visit yesterday, Sam told me he was feeling much better. Specifically, he was more energetic, felt less tired, and he and his wife were now having sex again. Sam's body composition had changed too. Testing revealed his body fat had decreased from 34% to 30%- still high, but a very impressive improvement. He had gained 2.5 pounds of muscle and lost over 10 pounds of fat! And his PSA was still undetectable, meaning there was still no evidence of cancer recurrence.
Until very recently, it was believed that higher T led to more rapid prostate cancer growth, hence the prohibition against T therapy in men with prior prostate cancer. The fear was that any "sleeping" prostate cancer cells would begin to divide more quickly in the presence of higher T, causing a recurrence of the cancer. Yet in a number of articles I've written on this subject, I discovered that the origin of this belief in prostate cancer's response to T was based on studies in the 1940s and 1960s, and only in men who had been castrated (a common, if unpleasant treatment for metastatic prostate cancer). Modern evidence indicates that in humans and animals, large changes in blood concentrations of T have little if any effect on prostate cancer growth. The one special case is that lowering T to zero (or almost zero), as with castration, does deprive prostate cancer of a needed nutrient, causing it to shrink.
Clearly, men like Sam can benefit greatly from T therapy, in terms of symptoms as well as overall health (there are important health benefits of having less fat and more muscle beyond the cosmetic ones).
At my lectures over the years, one of my favorite questions of physicians has been how many would treat a man like Sam with T therapy. Five years ago, barely a single hand would be raised in the audience. Two years ago I started seeing a handful. And at a recent debate, I was pleasantly surprised to see that approximately half the urologists in the room indicated they had treated men in Sam's situation. What an incredible change!
We don't yet have large studies to confirm the safety of the treatment, and so patients like Sam must be informed that treatment entails what I call an "unknown degree of risk" re cancer recurrence, but so far the data from a number of medical centers around the country appear to be quite reassuring.
Are there strongly held beliefs in your own field that have also persisted for many years based on old information that may no longer be correct? I'm curious to hear.
