Race, inflammation, and prostate cancer: A comparison of African Americans and Caucasians.

Abstract

246 Background: African-Americans (AA) have the highest rate of prostate cancer (PCa) incidence and mortality. Studies have shown higher rates of chronic prostate inflammation in AAs compared to Caucasians (CA). In order to better understand racial disparity in PCa and chronic inflammation (CI), this study examined the effects of race and CI on clinical parameters among PCa patients. Methods: This retrospective study sample consisted of 61 AA and 52 CA PCa patients who underwent radical prostatectomies (RP) at Tulane Hospital between 2013 and 2015. Clinical data was extracted from biopsy and RP pathology reports. The study examined the relationship between CI, race, percent of positive cores, extra-prostatic extension, PSA, PSA density, urinary PCA3 and TMPRSS2, and prostate size (g). Pearson’s chi-square, Fisher’s exact, and Kruskal-Wallis tests were used to analyze categorical, non-continuous data; ANOVA tests were used to analyze continuous data. Differences between biopsy and surgical/pathologic Gleason scores and clinical/pathological stages were also assessed. Results: 94 patients (52 AAs and 42 CAs) had CI to some degree and 19 did not (9 AAs and 10 CAs). There was no difference in rate of CI between AA and CA patients (P = 0.526). Among all patients sampled, AAs had higher percentages of positive cores (P = 0.005), PCA3 copy levels (P =0.004), and PCA3 scores (P <0.001), lower TMPRSS2 scores (P =0.039), and were more likely to have “high” or “intermediate” NCCN risk strata (P =0.010). Among patients with CI, AAs were more likely than CAs to have extra-prostatic extension (P =0.026) and less likely to have undergone a prior prostate biopsy (P =0.043). Patients without CI were more likely than patients with CI to have positive tumor margins (P =0.035) and SV invasion (P =0.013). There were no significant relationships between race and CI, and changes in either total Gleason score or stage from biopsy to RP. Conclusions: This study showed that AAs and patients without CI had more advanced forms of PCa (possibly due to PSA detection biases). Findings did not reveal any significant link between race and CI. Larger studies are needed to confirm these results and better understand the relationship between race, CI, and PCa.