A comparative study of a double-line versus a fan-shaped technique for obtaining transrectal ultrasound-guided biopsies of the prostate

Abstract

Introduction and objectives: Transrectal ultrasound-guided biopsy of the prostate is an established method to obtain prostate specimens for histological analysis. The aim of this prospective study was to compare the prostate cancer detection rate of the conventional double-line biopsy to a more fan-shaped biopsy technique.

Methods: A total of 107 men were included in this study. The indication for performing a prostate biopsy was a serum prostate-specific antigen level exceeding 4 ng/ml and/or suspicious findings on digital rectal examination. 53 patients were biopsied by the conventional double-line technique (method A): 3 biopsies in the midparasagittal plane from each lobe at the apex, middle and basis, at an angle of approximately 45 degrees C. 54 patients were biopsied with the so-called fan-shaped technique (method B): 6 biopsies were taken from the left to the right lateral margin in one plane at the same angle.

Results: 642 prostate biopsy cores were obtained, a subset of 133 biopsies were identified to yield prostate cancer. The percentage of positive biopsies was higher in group B (n = 81; 61%) as compared to group A (n = 52; 39%). The overall prostate cancer detection rate by the fan-shaped technique was 37% (20/54) as compared 30.1% (16/53) to the conventional double-line technique, but this difference did not reach statistical significance (p < 0.05) presumably because of the small number of patients.

Conclusion: These data suggest that the fan-shaped biopsy technique seems to have a higher cancer detection rate and a higher number of positive core biopsies than the conventional double-line technique, because of more presence in the apex and the peripheral zone of the prostate where most prostate cancers originate from.