Young men who smoke pot may be putting their manhoods in the line of fire, according to new research from the University of Southern California. The study, published in the journal CANCER, links marijuana to non-seminoma tumors—a particularly dangerous form of testicular cancer—in males between their early teens and early thirties. “The group that is at risk for developing these tumors is overwhelmingly young men. They should be looking and paying attention to changes in their testicles anyway,” says Victoria Cortessis, one of the study’s authors and an assistant professor at USC’s Keck School of Medicine. Cortessis and her colleagues asked 163 young men with testicular cancer, and 292 healthy men, about their drug use. They found those who smoked pot had double the risk of developing testicular tumors—and the pot-smokers’ tumors tended to grow faster and be more difficult to treat. Although the exact reason for this correlation is yet unknown, in animal studies, pot smoke and the chemical THC have been known to reduce testosterone, which regulates testes development and function. “It may be that marijuana use disrupts this regulation in a way that makes the testes much more vulnerable to cancer,” says Coressis.
It’s not the first time this link has been flagged. “We now have three studies connecting marijuana use to testicular cancer, and no studies that contradict them,” says Stephen Schwartz, an epidemiologist at the Fred Hutchinson Cancer Center in Seattle who authored a 2009 study yielding similar results. “I think we should start taking notice.” According to the National Cancer Institute, over 8,500 men will be diagnosed with testicular cancer in 2012—with 360 estimated fatalities. However, those with non-seminoma tumors have a much higher fatality rate, so male pot-smokers—especially young ones—might be advised to keep an eye on their junk.
