Efficiency of 6- and 12-punctures biopsies to detect prostate cancer in patients with PSA< 10 ng/mL and normal digital rectal examination

OBJECTIVE: Establish the efficiency of 6- and 12-punctures transrectal ultrasound-guided needle biopsies in low risk patients for prostate cancer. Six-punctures (sextant) biopsies were compared to 12-punctures biopsies, assessing which is the best strategy to detect this neoplasm. MATERIALS AND METHODS: Among 240 patients submitted to prostate biopsy, 54 with suspected small and organ-localized tumors (prostatic specific antigen < 10 ng/mL and digital exam of the prostate not suggesting cancer) in glands < 50 cm³ were selected, constituting a homogenous sample. These patients were submitted to standard 3-punctures (basal, mid, and apical) sextant biopsy in parasagittal midline of each prostatic lobe, with 3 additional lateral punctures, bilaterally. Each specimen was separately submitted to histological study. RESULTS: Twenty-two (40.7%) patients had prostatic cancer, and 28 presented prostatic hyperplasia, associated or not to inflammatory conditions. High-grade prostatic intraepithelial neoplasia (PIN) was detected in 4 patients. From 22 tumors detected by 12-punctures biopsies, 6-punctures biopsies in the parasagittal midline (sextant) diagnosed 50% of the cases, while isolated lateral punctures diagnosed 90.9% of the malignant neoplasms. Basal lateral punctures responded for 72.7% of the cancer diagnosis, while basal sextant punctures responded only for 9.1% of the cases. CONCLUSION: For low risk prostate cancer, patients’ 12-punctures biopsy was more effective, for sextant biopsy failed to diagnose half of the cases of neoplasm. Three lateral punctures (basal, mid, and apical), with 2 additional punctures in the parasagittal midline (mid and apical) bilaterally are suggested as the best biopsy strategy.