Prevalence and predictors of cannabis use among men receiving androgen-deprivation therapy for advanced prostate cancer

Can Urol Assoc J. 2020 Jan;14(1):E20-E26. doi: 10.5489/cuaj.5911. Epub 2019 Jun 17.


Introduction: Prostate cancer patients receiving androgen-deprivation therapy (ADT) often experience a combination of disease symptoms and treatment side effects. The therapeutic use of cannabis to alleviate these side effects has not been studied, despite increasing patient interest. With the increasing availability of cannabis, it is important for clinicians to understand the prevalence, predictors, and perceived benefits of cannabis use among patients with prostate cancer.

Methods: A total of 222 men undergoing ADT were assessed in this two-part study. In part one, the cannabis-use questionnaire was administered to 56 men, probing demographics, usage habits, perspectives, and degrees of symptom relief related to cannabis use. In part two, 191 cryopreserved urine samples were retrieved and analyzed for the presence of tetrahydrocannabidiol (THC) metabolite 11-nor-Δ9-THC-COOH. The respondents were then stratified into two groups, users vs. non-users, and statistical analyses were conducted.

Results: Questionnaire data revealed that 23.2% of surveyed men had recently used cannabis. In contrast, 5.8% of men had detectable levels of THC metabolite in their urine. Combined questionnaire and urine data revealed that cannabis users were significantly younger (p=0.003) and had lower testosterone levels (p=0.003) than non-users. The majority of men experiencing common ADT side effects reported some degree of relief following cannabis use.

Conclusions: Cannabis use among men with advanced prostate cancer receiving ADT is more prevalent than in the general population and the majority of other oncological cohorts. Lower testosterone levels and reported therapeutic benefit among cannabis users warrants confirmation in appropriate clinical trials.