In the context of a possible role of chronic inflammation in cancer risk, Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) have received attention for their potential as chemopreventive drugs against cancer. Therefore, we investigated the role of NSAIDs use in relation to prostate cancer aggressiveness among African and European Americans using data from the North Carolina-Louisiana Prostate Cancer Project (PCAP).

PCaP is a population-based, case-only study of incident prostate cancer in two southern U.S states. Overall, 2258 men (1130 African Americans and 1128 European Americans) newly diagnosed with prostate cancer between 2004 and 2009, aged 40 to 79 years and residing in North Carolina or Louisiana at diagnosis have been visited in their home by trained nurses who administered a standardized questionnaire on background characteristics, occupation, comorbid conditions and medications, health care access, prostate cancer diagnosis and screening history, diet, vitamins and supplements use and physical activity. Nurses also collected information of historic (five years prior to prostate cancer diagnosis) and current (within the two weeks prior to the in-home visit) use of NSAIDS. Historic NSAIDs use was self-reported by the patient (frequency, duration and product name) and current use was obtained by a review of all medications and their bottles used in the two weeks prior to the in-home visit (product name and concentration). Cancer aggressiveness was achieved using Gleason Sum abstracted from medical records. Aggressive prostate cancer was defined by Gleason sum>7 or Gleason sum=7 when the two most frequently represented grades in the tumor analyzed were 4+3. Multivariate unconditional logistic regression models were used to estimate Odds Ratios (ORs) and their 95% confidence interval (95% CI). Analyzes were performed in all men as well as stratified by race and age (<60 years,≥60 years).

NSAID use 5 years prior to diagnosis was not associated with aggressive prostate cancer (OR=0.97, 95% CI: 0.77–1.21), whether among African Americans or European Americans. There was no dose-response relationship either with frequency or duration. After stratification on age, we observed an inverse association between NSAID use and aggressive prostate cancer among men under the age of 60 (OR=0.62, 95%CI: 0.40–0.94), with a more pronounced association for at least 10 years of use (OR=0.37, 95% CI: 0.15–0.92) and a use of more than 1 per day (OR=0.42, 95% CI: 0.22–0.83). A chronic use, defined by a use during at least 5 years prior to diagnosis and a use at time of diagnosis, was not associated with aggressive prostate cancer overall (OR=0.84, 95% CI: 0.64–1.11) or in African Americans (OR=1.11, 95% CI: 0.76–1.64), but was inversely associated with aggressive prostate cancer in European Americans (OR=0.64, 95% CI: 0.43–0.96). Interestingly, an inverse association was observed overall for men who used NSAIDs preferentially acting on COX2 (OR=0.39, 95% CI: 0.19–0.82), specifically observed in European Americans (OR=0.33, 95% CI: 0.11–0.99) even though results are based on small numbers.

Our results suggest an inverse association between a chronic use of NSAID and prostate cancer aggressiveness, particularly in men who used preferential COX2 inhibitors, and in European Americans. Those results need further investigations to be confirmed.