Outcomes of transrectal ultrasound scan of the prostate with sector biopsies for 323 New Zealand men with suspicion of prostate cancer.

AIMS

To assess the results and clinical outcomes of the first four years of transrectal ultrasound scanning (TRUS) with sector biopsies of the prostate, as the definitive second-line investigation for men with suspicion of prostate cancer, including comparability with subsequent information from histology of surgical specimens.

METHODS

Information was collated from the author's ongoing surgical audit. TRUS and sector biopsies were carried out as a rooms procedure using a Toshiba Sono-Layer SSA-270A ultrasound machine with a PVL 725 RT transrectal probe and biopsy guide. Six or eight sector biopsies were taken with a Manan biopsy gun using 18 French gauge biopsy needles. Prophylactic ciprofloxacin and tinidazole were administered. Men with suspicion of prostate-specific antigen assay or digital rectal examination were considered for the investigation, especially if they were candidates for potentially curative treatments.

RESULTS

Of 330 TRUS procedures performed on 323 men, 328 were done in rooms under local anaesthetic. The only significant complication was a transient bacteraemia in one patient not taking the antibiotics. Twenty men had prostate intraepithelial neoplasia or atypia, and 94 (29%) had cancer, of whom 24 (25%) had evidence of metastases. Curative treatment by radical prostatectomy or radiotherapy was attempted in 62 men (66%) and 28 are being managed by surveillance only. Comparisons with subsequent radical prostatectomy in 44 men showed that if only one TRUS biopsy core was involved with cancer (15 men), surgical margins were clear. For those with more cores involved (29 men), one-third (9 men) had positive margins or capsular perforation. The Gleason Score was different, more often higher, for 29 men by histology at radical prostatectomy compared to TRUS. Twenty-eight men had a subsequent transurethral resection of the prostate of which the histology resulted in management changes for ten of the 28, including three who were placed on surveillance and seven who underwent radical prostatectomy.

CONCLUSIONS

TRUS and sector biopsy is a tolerable rooms procedure for men with suspician of prostate cancer. Complications are rare if prophylactic antibiotics are taken. The procedure provides information of sufficient quality to advise patients further. No defects in specificity were detected. Defects in sensitivity were demonstrated by comparison with later histology following transurethral resection. Therefore, men with benign results at TRUS need ongoing follow-up. TRUS histology tends to underestimate the extent of cancer present as determined by subsequent radical prostatectomy histology. When used with prostate-specific antigen and digital rectal examination, TRUS and sector biopsy is capable of detecting prostate cancer before it has metastasized, more reliably than if symptoms are awaited before diagnosis is attempted. It may also recognize forms of cancer of apparent low clinical significance which can be managed by surveillance.