Vishal S. Chandan

BACKGROUND: It is difficult to estimate the diagnostic accuracy of biopsy for prostate cancer because men with negative biopsy do not undergo radical prostatectomy and thus have no confirmation of biopsy findings. METHODS: We performed 18-core needle biopsies on autopsy prostates from 164 men who had no history of prostate cancer. Six-core biopsies were taken from each of the mid peripheral zone (MPZ), the lateral peripheral zone (LPZ), and the central zone (CZ). We tested associations between age and tumor characteristics and analyzed the sensitivity of biopsies at each site. All statistical tests were two-sided. RESULTS: Prostate cancer was present in 47 (29%) prostates. Of the 47 cancers detected, 20 were clinically significant according to histologic criteria. Tumor volume was associated with tumor grade (P = .012) and with age (P<.001). The biopsies from the CZ did not detect any cancer that was not present in biopsies of either the MPZ or LPZ. The sensitivity of the biopsies taken from the MPZ and LPZ together (53%, 95% confidence interval [CI] = 38% to 68%) was therefore the same as that of 18-core biopsies and was superior to that of biopsies of the MPZ alone (30%, 95% CI = 17% to 45%) (P = .003). The sensitivities of biopsies from the MPZ for clinically significant and insignificant cancer were 55% (95% CI = 32% to 77%) and 11% (95% CI = 2% to 29%), respectively, compared with 80% (95% CI = 56% to 94%) and 33% (95% CI = 17% to 54%) for those from the MPZ and LPZ combined. CONCLUSIONS: The ability to detect prostate cancer was more related to the biopsy site than to the number of biopsy cores taken. The 12-core biopsies, six cores each from the MPZ and LPZ, were most likely to detect the majority of clinically significant cancers but also detected many insignificant cancers. When the six-core biopsies from the CZ were added, no increase in sensitivity was observed.

PURPOSE: Chronic inflammation is associated with prostate cancer and benign prostatic hyperplasia. However, the prevalence of chronic inflammation in malignant and benign glands has not been compared. We evaluated the association of inflammation, benign prostatic hyperplasia and cancer in autopsied prostates. MATERIALS AND METHODS: We prospectively analyzed 167 autopsied prostates. Pathological analysis identified each focus of cancer, benign prostatic hyperplasia nodules and areas of acute or chronic inflammation. Any cancer focus or benign prostatic hyperplasia nodule involved directly with inflammation was recorded. The association of the prevalence of prostate cancer, benign prostatic hyperplasia and inflammation was statistically assessed. RESULTS: Inflammation was present in 113 (67.6%) of 167 cases. Chronic inflammation was identified in 88 (53%), acute inflammation in 6 (4%), and chronic inflammation and acute inflammation in 19 (11%) glands. In the majority of cases inflammation was present in the transitional zone. A total of 93 glands (56%) were involved with benign prostatic hyperplasia and 49 (29%) with cancer. Of the glands harboring benign prostatic hyperplasia 75% were also involved with chronic inflammation compared to only 50% of those without benign prostatic hyperplasia (p <0.01). Comparatively the glands with or without any evidence of cancer were similarly involved with chronic inflammation (55% vs 58%, p >0.1). Of the 27 glands involved with cancer and benign prostatic hyperplasia, chronic inflammation was more associated with benign prostatic hyperplasia than cancer (p = 0.006). Acute inflammation was not significantly associated with either benign prostatic hyperplasia or cancer. CONCLUSIONS: Chronic inflammation was a common finding in autopsied prostates. It appeared to be directly associated with the presence of benign prostatic hyperplasia but not with cancer.