Marijuana Use Increases Risk of Testicular Cancer

Jacob Schor, ND, FABNO

January 15, 2013



Since last November when the vote pretty much made it legal to possess marijuana in Colorado, we have been hearing and reading all sorts of predictions regarding what kind of impact we will see in our state.  Will we see more tourists coming on vacations that parallel the wine tasting visits people make to the Napa Valley?  I’ve already noticed that the Mary Jane Ski area up in Winter Park can’t keep their “No Jane, No Pain” bumper stickers in stock.


What I haven’t noticed as any concern about the potential negative impacts on health that this change in consumption levels may have, in particular any mention of Larson et al and their November 2012 suggestion that using marijuana increases risk of getting testicular cancer.


These researchers from the University of Southern California’s Department of Preventive Medicine surveyed 163 patients with testicular germ cell tumors (TGCT) and compared them with 292 matched controls.  Participants were questioned carefully about recreational drug use. Compared to those men who never used marijuana, those who reported that had used marijuana had a 2-fold increased risk (OR, 1.94; 95% CI, 1.02-3.68).  Curiously using cocaine appeared protective: ‘ever use of cocaine’ had a negative association decreasing risk of TGCT significantly by 46% (OR, 0.54; 95% CI, 0.32-0.91).  We haven’t much about that effect in the news either.



There are several other papers exploring this association, enough that we can’t easily ignore these findings.


A December 2012 paper in Cancer examined the age of first marijuana use and development of TGCT.


Incidence of testicular cancer has been increasing over the last few decades and no one is quite sure why.  Risk factors are not well understood.  Chemical exposure in utero or in early childhood may be major determinants.  Two occupations put men at higher risk for exposure, fire fighting and aircraft maintenance, also increase risk.  No association has been found to diet or exercise. 

Thus finding this significant impact from marijuana use stands out.





Lacson JC, Carroll JD, Tuazon E, Castelao EJ, Bernstein L, Cortessis VK.  Population-based case-control study of recreational drug use and testiscancer risk confirms an association between marijuana use andnonseminoma risk.  Cancer. 2012 Nov 1;118(21):5374-83.


Lacson JC, Bernstein L, Cortessis VK. Potential impact of age at first marijuana use on the development of nonseminomatous testicular germ cell tumors.  Cancer. 2012 Dec 11.


McGlynn KA, Trabert B. Adolescent and adult risk factors for testicular cancer. Nat Rev Urol. 2012 Apr 17;9(6):339-49.