The presence of chronic inflammation in benign prostate tissue has been found to be linked with high-grade, or aggressive, prostate cancer, and this association was found even in those with low prostate-specific antigen (PSA) levels.
An analysis of prostate tissue biopsies collected from some participants of the placebo arm of the Prostate Cancer Prevention Trial (PCPT) found that those whose benign prostate tissue had chronic inflammation had 1.78 times higher odds of having prostate cancer, and 2.24 times higher odds of having an aggressive disease (characterized by Gleason sum of seven to 10), compared with those whose benign prostate tissue had no inflammation.
"We had the unique opportunity to investigate biopsy tissue from patients who had no indication to prompt a biopsy," Elizabeth A. Platz, Sc.D., MPH, professor in the Department of Epidemiology at the Johns Hopkins Bloomberg School of Public Health in Baltimore, Md said.
"Participants in the PCPT who were not diagnosed with prostate cancer during the trial were recommended to undergo prostate biopsy at the end of that trial, which meant that prostate tissue was available not just for men who had the diagnosis of prostate cancer, but also for those who did not have the diagnosis.
"We found that men who had at least one biopsy core with inflammation had a higher likelihood of having high-grade prostate cancer compared with those who did not have any inflammation in their biopsy tissue," Platz said.
"While we know that inflammation is common in prostate tissue from men who have some indication to prompt a biopsy, such as high PSA or an abnormal digital rectal examination [DRE], we were surprised to find that the prevalence of chronic inflammation in the men who didn't have any such indication was really high, about 78 percent," she added.
The study is published in Cancer Epidemiology, Biomarkers and Prevention, a journal of the American Association for Cancer Research.