[Clinical impact of body mass index on prostate biopsy in patients with intermediate PSA levels].

From April 2005 to September 2007, 480 patients underwent transrectal prostate biopsy at our institution. The clinical data including age, serum prostate specific antigen (PSA) level, prostate volume and body mass index (BMI) were obtained, and the cancer detection rates and pathological findings were evaluated in 305 cases with a PSA concentration of 4.0 to 10.0 ng/ml. Prostate volume was calculated from magnetic resonance imaging (MRI) findings. The 305 patients were categorized according to their BMI into three groups (normal, less than 22 kg/m2 ; overweight, 22-25 kg/m2 ; and obese, more than 25 kg/m2). Cancer detection rates and histopathologic findings were compared between the groups. Multivariate logistic regression analysis was also performed. Prostate cancer was detected in 127 patients. No significant differences in BMI were observed between biopsy-positive and biopsy-negative cases (p = 0.965), and the detection rates of prostate cancer observed in the three groups were not significantly different. There was a significant association between BMI and the findings of high Gleason score (more than 4+3) (p = 0.048). BMI was not a contributory factor of prostate cancer detection for cases with intermediate PSA levels; however, patients with high BMI may have high-grade malignancy features.