Importance of Malignant Core Length in the Detection of Clinically Significant Prostate Cancer in Transrectal Prostate Biopsies

Objective: To examine cores obtained using prostate biopsy under transrectal ultrasound guidance and determine the ideal total malignant core length for the diagnosis of clinically significant prostate cancer (PCa). Materials and Methods: From the beginning of 2017 to the end of 2021, 1.611 transrectal ultrasonography-guided prostate biopsy procedures were retrospectively analyzed. The data were divided into two groups as PCa and non-cancer (non-Ca) according to the pathology reports. The PCa group was further divided into two subgroups as clinically significant and non-significant. After comparing the core numbers and lengths between the groups, a statistical analysis was undertaken to determine the optimal cut-off value of the total malignant core length in predicting the diagnosis of clinically significant PCa. Results: A total of 1.181 biopsy procedures were included in the evaluation. The mean malignant core lengths of the clinically significant and non-significant PCa groups were 6.7±5.1 and 3.6±2.9, respectively, indicating a statistically significant difference between these subgroups. In the presence of PCa, the mean length of malignant cores was found to have an area under the curve value of 0.708 (95% confidence interval: 0.654-0.759) in the prediction of clinically significant PCa, and it had 56.44% sensitivity and 78.05% specificity at a cut-off value of >4.7 cm. Conclusion