New research suggests Peyronie’s Disease, which causes a man’s penis to curve, may be linked to an increased risk of cancer. The study, published in the Sterility and Fertility, is enough to make any man hustle to the nearest stall to check on the jogs in his junk. The problem is that curved penises are common, Peyronie’s is fairly rare, and the increased risk is negligible.
For the study, Baylor College researchers looked into the urologic health of 1.5 million middle-aged men, based on data collected through insurance claims. Of those men, 48,000 were diagnosed with Peyronie’s disease, one million were diagnosed with erectile dysfunction, and about 480,000 acted as healthy controls. The researchers then looked at the men’s medical records to see which among them had developed cancer four years later. The results suggest that a diagnosis of Peyronie’s disease increases the risk of stomach and testicular cancer by 40 percent and the risk of melanoma by 29 percent. Startling, sure. But there are caveats.
First of all, just because you have a parabolic penis does not mean you have Peyronie’s. A slight curve in the penis is common, and those who sport a gentle arch rather than a pronounced bottleneck need not worry. Peyronie’s also predominantly affects men in their 40s, and is present in less than one percent of the population. It usually develops after trauma to the penis when, as part of the healing process, a plaque forms that causes a sharp kink in the shaft.
But even if you do have Peyronie’s, it’s important to look critically at increased risk. National statistics suggest that your lifetime risk of testicular cancer is about 0.4 percent. Your lifetime risk of stomach cancer is 0.8 percent; your melanoma risk is 2.2 percent. So a 40 percent increased risk puts your lifetime for testicular cancer at 0.56 percent (an increase of merely 0.16 percentage points) and your lifetime risk of stomach cancer at 1.12 percent (an increase of 0.32 percentage points). A 29 percent increased risk of melanoma just means that your lifetime risk increases to 2.84 percent—in other words, an increase of 0.638 percentage points.
Add in the fact that this study was retrospective and highlights correlation, not causation, there’s little reason for the vast majority of men with curved penises to worry about these results. At the same time, if your penis is particularly bent or intercourse becomes painful and you suspect Peyronie’s, it’s certainly a good idea to call a urologist and get it checked out.