Stellenwert der Rebiopsie in der Diagnostik des Prostatakarzinoms

Abstract

The objective of this study was to evaluate whether rebiopsy of the prostate leads to a significant increase in the detection rate of prostate cancer compared with performing a single biopsy. Data from 406 patients were evaluated retrospectively. The patients had undergone ultrasound-guided transrectal biopsy of the prostate between January 2004 and August 2005. Besides demographic data, the patient information was reviewed with regard to the number of biopsy samples taken per patient, histological results, and the occurrence of complications during or after the examination. If prostate cancer was detected, data acquisition included the number of positive biopsy samples taken per examination as well as the subsequent therapy and the TNM classification of the tumor. After a follow-up time between 24 and 42 months, all patients with a histologically negative first biopsy were reevaluated regarding rebiopsy. We evaluated the follow-up time (in months) and the histological results. If prostate cancer was detected, we assessed the number of positive biopsy cores as well as the subsequent therapy and the TNM classification. In 37.7% of all patients (n=153), prostate cancer was detected in the first biopsy. In 56.9% of these (n=87), a high-grade carcinoma with a Gleason score >or=7 was diagnosed. In 108 patients, a second biopsy was performed. The mean time between the first biopsy and rebiopsy was 21.7 months (range 1.3-41.2 months). With the second biopsy, prostate cancer was detected in 29 cases (26.9%), of which 51.7% (n=15) showed a high-grade carcinoma. There was no significant difference between the first biopsy and the second biopsy concerning either the detection rate of carcinomas related to the total number of transrectal multibiopsies or the detection of high-grade carcinomas related to the number of detected carcinomas. Provided that values beyond the second standard deviation were excluded from analysis, prostate-specific antigen (PSA) values at the time of rebiopsy were significant elevated compared with PSA values at the time of first biopsy. More than two-thirds of all patients with a histologically positive result in the second biopsy revealed a PSA velocity >or=0.6 ng/ml/year. Furthermore, there was no significance between the number of histologically positive samples per multibiopsy when prostate cancer was diagnosed in the first biopsy compared with the number of positive samples in the second biopsy. Complications after biopsy were noted in 19 patients. In three cases, hospitalization was necessary. As a result of performing a rebiopsy, the detection rate of prostate cancer increased significantly compared with the detection rate after a single biopsy. Thus, the number of patients who could receive therapy was also increased. Due to the relatively low complication rate of prostate multibiopsy, this examination can be widely indicated. There was not a higher detection rate of high-grade prostate cancer in the second biopsy compared with performing only a single biopsy. The indication for a second biopsy as well as the determination of the time interval between the first and second biopsy should consider the current PSA value and PSA dynamics. Therapeutic consequences should also be taken into consideration. In the event of a PSA velocity >0.6 ng/ml/year, a rebiopsy should definitely be performed.