Ces Urol 2013, 17(4):238-245 | DOI: 10.48095/cccu2013035

Does prostate re-biopsy have to include a biopsy of the transitional zone?

Martin Hrabec¹, František Záťura¹, Ladislava Kučerová², Vladimír Študent¹

¹ Urologická klinika LF UP a FN, Olomouc

² Ústav patologie LF UP a FN, Olomouc

Aim:
The aim of our study was to assess the precise tumour localization in radical prostatectomy specimens. Based on the study outcome, we are proposing a modification to the prostate biopsy strategy with the goal of increasing the tumour detection rate.

Material and methods:
Between May 2008 and June 2011 we evaluated whole mount section of 33 prostates (specimens were obtained by 23 radical retropubic and 10 robot-assisted radical prostatectomies). Tumour localization was assessed according to McNeal's prostate zonal anatomy scheme. Statistical analysis was performed using a chi-square test.

Results:
In all cases, the tumour was localized in the peripheral zone (PZ) of the prostate. In 30% of specimens a tumour was also found in the transitional zone (TZ). Neither of the TZ findings involved index tumours. In 15% of cases, separate tumour foci were found in the TZ, which did not affect the patient's prognosis. In the remaining 15% of cases, a large peripheral tumour infiltrated the TZ. We failed to detect a case with the tumour focus presenting with TZ only. In cases of TZ tumour localization, 60% of patients presented with a locally progressive disease. In the case of tumours localized to the PZ, locally advanced prostate cancer was diagnosed in only 13% of the specimens (statistically significant difference, p = 0,005). In TZ tumours, PSA progression after radical prostatectomy was seen more frequently (in 50% of patients), in contrast to non-TZ tumours where progression developed in 30% of cases. This difference was found to be statistically insignificant (p > 0.05).

Conclusion:
During its early stages, prostate cancer is always localized in the PZ. In all cases where the tumour was found in the TZ locations, it was associated with a simultaneous PZ tumour focus or with a central progression of PZ tumour. It is therefore necessary to direct the biopsies into the PZ and we propose the use of a peripheral zone biopsy not only in the course of the initial biopsy, but also in the rebiopsy A TZ biopsy is indicated when a saturation biopsy is performed in cases where there is suspicion of prostate cancer due to PSA elevation above 10 ng/ml, in addition to repeated prostate biopsies with negative histology findings.

Keywords: prostate cancer, tumour localization

Received: March 12, 2013; Accepted: August 12, 2013; Published: September 1, 2013