[Establishment of a nomogram for predicting positive repeat prostate biopsy in Chinese men].

OBJECTIVE: To develop a nomogram for predicting the probability of prostate cancer at transrectal ultrasound-guided repeat prostate biopsy in Chinese men.

METHODS: We performed repeat biopsy for 170 patients with benign prostate diseases diagnosed on the first biopsy, and analyzed the correlation of positive repeat biopsy with age, prostate volume, PSA, free-to-total PSA (f-PSA/t-PSA), PSA velocity, PSA density, results of digital rectal examination (DRE) and previous histology. We entered the variables stepwise into logistic regression models, and established a nomogram for the risk score on the probability of positive repeat biopsy, whose predictive value was assessed by receiver operating characteristic (ROC) analysis.

RESULTS: Prostate cancer was detected in 31.8% of the repeat biopsies (54/170). The most accurate predictive nomogram comprised age, PSA, f-PSA/t-PSA, PSA velocity, prostate volume, DRE and previous prostatic intraepithelial neoplasia (PIN) findings. The nomogram exhibited a high predictive value, with the area under the ROC curve (AUC) of 82.4%, significantly greater than that of the prediction based on PSA density (AUC: 66.9%), prostate volume (AUC: 72.6%), PSA velocity (AUC: 69.6%), f-PSA/t-PSA (AUC: 69.3%), or DRE (AUC: 58.5% ) alone.

CONCLUSION: The nomogram is an accurate multi-variable predicting tool to determine the probability of positive repeat prostate biopsy.