Features of inflammatory response in benign prostatic hyperplasia and prostate cancer depending on the presence of viral infection

Introduction. Chronic infections and inflammatory diseases contribute to the development of malignancies. An association between chronic inflammation and prostate cancer has recently been hypothesized, as inflammatory infiltrates are detected in patients with prostate cancer and benign prostatic hyperplasia, with chronic inflammation in the latter nearly doubling the risk of prostate cancer. Viral infections may contribute to chronic inflammation and carcinogenesis, but data on prostatic hyperplasia are inconsistent. We aimed to identify the features of inflammatory response in patients with benign prostatic hyperplasia and prostate cancer with and without viral infection. Materials and methods. The study included biopsies and surgical specimens from 145 patients operated on benign prostatic hyperplasia and prostate cancer. We performed microscopic and real-time polymerase chain reaction examination for human papillomaviruses, human simplex herpesviruses 1 and 2, cytomegalovirus, Epstein-Barr virus, and human herpesvirus 6. Based on the results of polymerase chain reaction examination, patients were divided into 4 subgroups: benign prostatic hyperplasia with and without a viral infection and prostate cancer with and without viral infection. Fifteen samples from each subgroup were stained with hematoxylin and eosin using the standardized histologic classification and then analyzed to evaluate inflammation response. Results. In viral infection, the prostate was characterized by a periglandular pattern of inflammatory infiltration, multifocal prevalence of infiltration, and moderate-to-severe inflammation intensity. In contrast, patients without viral infection showed a weaker focal stromal inflammatory infiltration. Conclusion. Viral infection in prostate tissue in both benign prostatic hyperplasia and prostate cancer leads to a greater prevalence and intensity of inflammatory infiltration centered around the glandular component of the prostate, which may indicate differences in pathogenesis of these diseases and be important for diagnosis and therapy. Keywords: benign prostatic hyperplasia, prostate cancer, viral infection, inflammation