How many of you have already had a patient get in touch about this latest scare? As one expects nowadays, I first heard about this paper on Twitter within a few minutes of it being published, but it wasn’t long after that a recent patient of mine rang my rooms to challenge me about the reassurance I had given him only last week about the lack of increased risk of prostate cancer, which he had specifically asked me about. And of course since then, we have had headlines in the mass media all over the world alerting us to the results of this 24-year study that suggests that vasectomy confers an increased risk of not just prostate cancer, but high-grade prostate cancer in men undergoing vasectomy. Here are just some of the headlines:
So what are we to make of all this? Vasectomy counselling has always been a challenging area due to the well documented possibilities of early and late failure, and also of the ever present issue of chronic scrotal pain. And while the area of prostate cancer risk has been raised previously, I must say I have always felt comfortable saying that on balance, the increased risk of developing significant prostate cancer following vasectomy proved to be minimal. “Don’t worry about it” was my typical blithe reassurance. Do I have cause to change my advice now?
Let’s look at this paper from Siddiqui et al. The data is taken from the well-known Health Professionals Follow-up Study (HPFUS), which originally enrolled almost 50,000 men aged between 40 and 75 back in 1986. Of these, about 12,000 (25%) underwent vasectomy and 6000 of these (12.2% of population) were subsequently diagnosed with prostate cancer over the 24-year follow-up period. Of these, 811 (1.6%) died of prostate cancer. The authors calculate that vasectomy was associated with a small overall increase in the risk of prostate cancer (RR = 1.10). However the headlines are coming from the higher relative risk of 1.22 among men subsequently diagnosed with high-grade prostate cancer (Gleason 8 to 10). Also, vasectomy appeared to confer a higher relative risk (1.19) of actually dying of prostate cancer or developing distant metastases compared to men who did not undergo vasectomy. It is these findings that vasectomy appears to confer not just an increased risk of prostate cancer, but an increased risk of developing aggressive or a lethal prostate cancer, which has provoked some concern.
This topic is not new and other studies have shown that this risk does not exist or at best, the risk is minimal and the quality of evidence not good enough to change practice. Does this current paper change all that? It will certainly change the nature of counselling for men considering vasectomy as there may well be a case to consider. As the population of men presenting for vasectomy are not a typical population who would be counselled about the early detection of prostate cancer, perhaps this other difficult counselling area also needs to be broached.
Declan Murphy is a urologist at Peter MacCallum Cancer Centre in Melbourne, Australia, and Associate Editor at BJUI. Twitter @declangmurphy