[Two methods for transrectal ultrasound-guided biopsy of the prostate: systematic vs. guided for suspect echogenic lesion].

Objective: We undertook this study to determine the efficiency of ultrasound-guided transrectal prostate biopsy applying two techniques: systematic extended vs. suspicious sonographic areas.

Methods: Medical files and histopathological reports were reviewed of patients who were treated at the Specialties Hospital of the 21st Century Medical National Center in Mexico City with suspicion of prostate cancer (T1, T2 and PSA <10 ng/ml). Patients had ultrasound-guided transrectal prostate biopsy applying two techniques: systematic extended vs. hypoechoic suspicious sonographic areas. Studies were carried out from January 1, 2005 to July 2006.

Results: Of 145 selected patients submitted to ultrasound-guided transrectal prostate biopsy, systematic extended biopsy (group I) was carried out in 73 (50.3%), taking on average 11.75 cylinders per patient. In 72 (49.6%) patients, biopsies were taken on suspicious sonographic areas (group II), taking on average 4.02 cylinders. In group I, 36 (49.3%) patients were positive vs. group II, where 20 (27.7%) patients were positive (p <0.01) with an estimation of risk in favor of group I, determining a probability 2.5 times higher of positivity with this technique (95% confidence interval: range 1.2-5) and a better performance in 22%.

Conclusions: Systematic extended ultrasound-guided transrectal prostate biopsy represents a technique with a higher rate of efficiency than using ultrasound-guided transrectal prostate biopsy in suspicious sonographic areas and has proven over time to be the superior prostate biopsy technique for diagnosis of prostate cancer. It must be considered the method of choice.