To minimize confounding factors of PSA level in subgroup analysis with different prostate volume, CMH test was performed, showing that TR group still have a higher cancer detection rate than the TP group with 30–80 mL prostate volume (OR: 1.838, 95% CI: 1.086–3.112, p = 0.023), while there was no significant difference in cancer detection rate in the subgroup with > 80 mL (p = 0.087). Here, KLK3 is linked to cancer.