Prostate cancer detection rates in different biopsy schemes. Which cores for which patients?

Purpose: To determine whether the addition of four paramedian peripheral and four lateral peripheral cores improves the cancer detection rate (CDR) of the extended 10-core biopsy scheme and which patients benefit most from such additional samples. Methods: One thousand and ninety-one consecutive patients scheduled for first ultrasound-guided transrectal prostate biopsy prospectively underwent a 18-core biopsy scheme, including the traditional sextant (6-core), 4 lateral peripheral (10-core), 4 paramedian peripheral (14-core) and additional 4 lateral peripheral cores (18-core). Results: The CDR of the 6-, 10-, 14- and 18-core schemes was 33.1, 39.2, 41.6 and 41.8 %, respectively; the difference between the 10- and 6-core scheme reached significance (p <0.005), whereas that between the 18- or 14- and the 10-core scheme did not. The percentage of tumors diagnosed on the sole basis of the 14-core scheme was significantly greater in patients with low PSA (≤7.2 vs. >7.2 ng/ml: 12.1 vs. 1.8 %; p <0.0001), large prostate volume (≥50 vs.