July 20, 2012
Many with Prostate Cancer Do Not Benefit From Surgery
My regular readers know that prostate cancer has been a controversial topic recently. The controversy centers around our ignorance of whether treating early prostate cancer helps patients, and by extension, whether early diagnosis is helpful. In May I wrote about the US Preventive Services Task Force’s new recommendation against screening men for prostate cancer with PSA blood testing, finding that the benefits of such screening are small or non-existent while the harms are large.
Nevertheless, for patients already diagnosed with prostate cancer choosing a treatment plan is fraught with anxiety but very little data. I wrote in 2006 that for some patient with newly diagnosed prostate cancer, electing to forego any treatment may be a reasonable choice. Still, a patient who has just been diagnosed with cancer is frequently unreceptive to the notion that he need not do anything. A study in this week’s New England Journal of Medicine attempted to clarify if surgery done to remove the prostate in patients diagnosed with prostate cancer improves their survival.
The study enrolled 731 men with newly diagnosed cancer that had not yet spread outside the prostate. These men were randomized to have surgery (radical prostatectomy) or to receive no treatment other than regular follow up and monitoring. They were followed for an average of 10 years.
The results were interesting but not definitive. The group that underwent surgery did not live longer than the group without treatment, nor did they have fewer deaths due to prostate cancer. Not surprisingly, the group that underwent surgery also had significantly more complications from surgery, primarily difficulty with erections and urinary incontinence. This would seem to suggest that surgery had no benefit despite significant harms. Given the huge number of men who undergo prostatectomy every year, the study has received much media attention. (See links below.)
But the conclusions from the study are not so clear. As an accompanying editorial in the New England Journal of Medicine points out, the study enrolled far fewer than the 2,000 patients it initially hoped to attract. The study therefore was not statistically able to detect small mortality benefits of surgery that may have appeared had more patients been followed for more years. Moreover, fewer men in the group that underwent surgery had their prostate cancer spread to their bones, a complication that can be painful and debilitating. Though less compelling than a mortality benefit, the prevention of bone metastases is a finding favoring surgery.
There was one additional important finding that favored surgery. Among the subset of men with tumors judged to be at high risk of spreading because of a PSA higher than 10 or because the cancer cells looked very abnormal microscopically, the men who underwent surgery lived longer than those who did not.
So the conclusion of this study is mixed. Men who have prostate cancer that is likely to be aggressive are likely to live longer if they have surgery. But men who have less than 10 years of life expectancy or whose prostate cancer is more indolent (by PSA and microscopic appearance) are very unlikely to benefit from surgery, while still suffering all the surgical complications.
The important but difficult lesson is not to panic after the diagnosis. There is plenty of time to collect opinions and choose the right course. And sometimes the right course is doing nothing.
Surgery unneeded for most early-stage prostate cancer, study says (Los Angeles Times)
Important legal mumbo jumbo: