Objectives: The objective of this study was to use computer simulation to investigate the optimal biopsy scheme for enhancing the detection of cancer in palpably benign prostate glands.
Methods: The predominant distribution of palpably benign prostate cancer is anterior apex to mid-prostate. We used computer simulation to optimize apical samplings and to simulate the biopsy procedure, including angle and length. A total of 254 consecutive patients with palpably benign prostate glands underwent sextant biopsy plus two additional deep apical biopsies.
Results: Based on the computer simulation, lateral sextant and two additional medially located deep apical cores with a sagittal penetration angle of 80 degrees had the maximum cancer detection. Of the 254 patients, 58 (22.8%) had prostate cancer: 28 (48.3%) were positive only at the standard sextant sites, 12 (20.7%) were positive exclusively at the deep apical sites, and the remaining 18 (31.0%) were positive at both sites. Patients with gray-zone prostate-specific antigen (PSA) ranges of 4.1-10.0 ng/mL had increased cancer detection rates of 24% compared to sextant biopsy. Enhanced cancer detection by the deep apical biopsy was also evident in patients with a prostatic volume >40 cm3 (by 36.4%) and PSA 2.1-4.0 ng/mL (by 13.3%).
Conclusions: Using a computer simulation-based biopsy scheme with deep apical sampling cores enhanced the detection of prostate cancer in palpably benign glands, especially in men with PSA ranges of 4.1-10.0 ng/mL or a gland volume of >40 cm3. Our approach with fewer sampling cores may have been more cost-effective than other extensive biopsy schemes, but further studies with larger samples are warranted.