Chronic intraprostatic inflammation may lead to a greater risk of developing prostate cancer 


Chronic intraprostatic inflammation may lead to a greater risk of developing prostate cancer. In our study we examined the results of prostate needle biopsies from 177 men between ages 47 and 83 years who were at high risk for developing cancer based on either high PSA scores or abnormal DREs. Of the 177 men, 144 or 81 percent were found to have chronic prostate tissue inflammation. We categorized the biopsies based on pathology. Of the 144 cases, 15 percent (22/144) had only inflammation, 15 percent (22/144 had simple atrophy, 39 percent (54/144) showed PAH/PIA (post-atrophic hyperplasia and/or proliferative inflammatory atrophy, which indicate evidence of chronic inflammation.) lesions and 8 percent, or 12/144, showed HGPIN – high-grade prostate intraepithelial neoplasia, which is a putative precursor to prostate cancer. Twenty percent, or 29/144, had cancer (adenocarcinoma) in the initial biopsies. In subsequent studies, 84 subsequent biopsies performed within five years in patients who had initially shown chronic prostate inflammation were analyzed. In the follow-up, 29 new cancer cases were diagnosed: six occurred in patients in whom initial biopsies showed only chronic inflammation, 15 in patients with initial PAH/PIA lesions, along with eight in patients with chronic inflammation and other risk factors for cancer (high-grade PIN and atypical small acinar proliferation suspicious for malignancy). In contrast, we found only two cases – 6 percent – in the 33 patients without inflammation who went on to develop cancer, both of whom had other risks factors for cancer.

The findings of this study suggest that there is a strong association between chronic prostatic inflammation and the development of pre-malignant and malignant changes in prostatic epithelium. The study raise two concerns:should patients with initial biopsies showing no malignancy, but showing chronic inflammation, be followed more closely and perhaps re-biopsied more frequently and is it wise to recommend watchful waiting to patients diagnosed with low-grade adenocarcinoma accompanied by chronic inflammation.?  

 

Bibliographical reference:

MacLennan GT et al.: "The influence of chronic inflammation in prostatic carcinogenesis: a 5-year followup study", J Urol. 2006 Sep;176(3):1012-6

 

Sanjay Gupta

Department of Urology, Case Western Reserve University, Cleveland, Ohio