Chronic inflammation on initial benign prostate biopsy is a negative predictor of subsequent cancer detection

Racial differences in the relationship between clinical prostatitis, presence of inflammation in benign prostate and subsequent risk of prostate cancer

BACKGROUND

Epidemiologic studies, primarily done in white men, suggest that a history of clinically-diagnosed prostatitis increases prostate cancer risk, but that histological prostate inflammation decreases risk. The relationship between a clinical history of prostatitis and histologic inflammation in terms of how these two manifestations of prostatic inflammation jointly contribute to prostate cancer risk and whether racial differences exist in this relationship is uncertain.

METHODS

Using a nested design within a cohort of men with benign prostate tissue specimens, we analyzed the data on both clinically-diagnosed prostatitis (NIH categories I-III) and histological inflammation in 574 prostate cancer case-control pairs (345 white, 229 African American).

RESULTS

Clinical prostatitis was not associated with increased prostate cancer risk in the full sample, but showed a suggestive inverse association with prostate cancer in African Americans (odds ratio (OR)=0.47; 95% confidence interval (CI)=0.27-0.81). In whites, clinical prostatitis increased risk by 40%, but was only associated with a significant increased prostate cancer risk in the absence of evidence of histological inflammation (OR=3.56; 95% CI=1.15-10.99). Moreover, PSA velocity (P=0.008) and frequency of PSA testing (P=0.003) were significant modifiers of risk. Clinical prostatitis increased risk of prostate cancer almost three-fold (OR=2.97; 95% CI=1.40-6.30) in white men with low PSA velocity and about twofold in white men with more frequent PSA testing (OR=1.91; 95% CI=1.09-3.35).

CONCLUSIONS

In our cohort of men with benign prostate specimens, race, and histological inflammation were important cofactors in the relationship between clinical prostatitis and prostate cancer. Clinical prostatitis was associated with a slightly decreased risk for prostate cancer in African American men. In white men, the relationship between clinical prostatitis and prostate cancer risk was modified by histological prostatic inflammation, PSA velocity, and frequency of PSA testing-suggesting a complex interplay between these indications of prostatic inflammation and prostate cancer detection.

Variation in reporting of cancer extent and benign histology in prostate biopsies among European pathologists

It is not known how uropathologists currently report histopathological features of prostate biopsies such as core length, tumor extent, perineural invasion, and non-tumor-associated features such as inflammation and hyperplasia in needle biopsies. A web-based survey was distributed among 661 members of the European Network of Uropathology. Complete replies were received from 266 pathologists in 22 European countries. Total core lengths were reported by 64 %. The numbers of cores positive for cancer was given by 79 %. Linear cancer extent was reported by 81 %, most often given in millimeters for each core (53 %) followed by the estimation of percentage of cancer in each core (40 %). A gap of benign tissue between separate cancer foci in a single core would always be subtracted by 48 % and by 63 % if cancer foci were minute and widely separated. Perineural invasion was reported by 97 %. Fat invasion by tumor was interpreted as extraprostatic extension by 81 %. Chronic and active/acute inflammation was always reported by 32 and 56 % but only if pronounced by 54 and 39 %, respectively. While most (79 %) would never diagnose benign prostatic hyperplasia on needle biopsy, 21 % would attempt to make this diagnosis. Reporting practices for prostate biopsies are variable among European pathologists. The great variation in some methodologies used suggests a need for further international consensus, in order for retrospective data to be comparable between different institutions.