Paul R et al. (2004) Influence of transrectal ultrasound probe on prostate cancer detection in transrectal ultrasound-guided sextant biopsy of prostate. Urology 64: 532–536

Transrectal ultrasound-guided biopsy is a widely accepted procedure in prostate cancer diagnosis, although little is known about the effects on the detection rate of different types of ultrasound equipment. Paul et al. hypothesized that end-fire ultrasound probes, which facilitate sampling in the most lateral part of the peripheral zone, would be superior to side-fire probes in the detection of smaller tumors. Their retrospective study comparing these two types of probe has recently been published.

A total of 2,625 patients underwent a first-time, systematic sextant biopsy using the Kretz Combisone side-fire probe, the Bruel & Kjaer Medical side-fire probe or the ATL HDI end-fire probe. The side-fire probes limited the prostate biopsy to a sagittal axis, whereas the end-fire probe allowed sampling in any section.

The overall prostate cancer detection rate (35.2%) was similar using all three probes. In a subgroup of patients with a PSA level of 4–10 ng/ml, however, the detection rate using the end-fire probe (31.3%) was statistically significantly higher than with either of the side-fire probes (P = 0.01). This was also the case in a further subgroup of patients with nonpalpable cancer.

In summary, the end-fire probe provided a higher prostate cancer detection rate in two patient subgroups, compared with the side-fire probes. The authors suggest that this was due to improved visualization of the lateral peripheral zone, in which most peripheral zone tumors occur.