Transperineal template-guided mapping biopsy as a staging procedure to select patients best suited for active surveillance.
OBJECTIVE
Patients with clinically insignificant prostate cancer are candidates for active surveillance. However, uncertainty regarding the true extent of disease limits enthusiasm. In this study, we report our initial findings in patients with transrectal ultrasound (TRUS)-detected clinically insignificant prostate cancer undergoing transperineal template-guided mapping biopsy (TTMB) as a staging procedure.


METHODS
Sixty-four patients who met the Epstein criteria for clinically insignificant prostate cancer underwent TTMB. Each biopsy core position was recorded in 3 dimensions with documentation of location of each positive biopsy core, Gleason score, percentage of involvement of each core, and presence/absence of perineural invasion.


RESULTS
Mean pre-TRUS prostate specific antigen was 4.7 ng/mL with a Gleason score of 6 involving a median of 5% of 1 TRUS core. The mean number of TTMB biopsy cores was 58.5, with 6.6 cores positive for malignancy. Ten patients had clinically insignificant prostate cancer (15.7%), 8 had no TTMB-detected cancer (12.5%), and 46 (71.9%) had clinically significant cancer. Of patients with cancer, 37 (66.1%) had bilobar involvement and 25 (44.6%) harbored a Gleason score of ≥7. In a multivariate analysis, tobacco consumption was found to be most closely related to clinically significant disease on TTMB.


CONCLUSIONS
TRUS biopsy underestimates disease extent and Gleason score in some patients. TTMB provides a more accurate assessment of the presence of aggressive histology.
Western Radiation Oncology, Mountain View, CA, USA.
Al V
AV
Taira
Gregory S
GS
Merrick
Abbey
A
Bennett
Hugo
H
Andreini
Walter
W
Taubenslag
Robert W
RW
Galbreath
Wayne M
WM
Butler
Nathan
N
Bittner
Edward
E
Adamovich
D000368:Aged; D000369:Aged, 80 and over; D006801:Humans; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D009367:Neoplasm Staging / Q000379:methods*; D011467:Prostate / Q000000981:diagnostic imaging / Q000473:pathology*; D017430:Prostate-Specific Antigen; D011471:Prostatic Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology*; D014463:Ultrasonography
D017430:Prostate-Specific Antigen