Comparative Study of Two Different TRUS–Guided Sextant Biopsy Techniques in Detecting Prostate Cancer in One Biopsy Session
Brössner C. ·
Madersbacher S. ·
Bayer G. ·
Pycha A. ·
Klingler H.C. ·
Eur Urol 2000;37:65–71 (DOI: 10.1159/000020102)
Objective: The aim of this study was to compare a transrectal ultrasound (TRUS)–guided sextant biopsy technique, which puts more emphasis on the apical region of the prostate where most prostate carcinomas (PCs) develop, with the standard sextant biopsy technique.
Methods: A total of 280 patients with suspected PC were included in this analysis. Twelve biopsy cores were obtained from all patients. Six biopsy cores were taken within a lateral parasagittal plane from each lobe at the apex, middle and basis, with an angle of approximately 45° (technique A), and 6 further biopsy cores were taken from the left to the right lateral margin always penetrating the prostate in the apex with the same angle (socalled fan–shaped technique, technique B). Technique A predominantly samples in the sagittal and technique B samples more in the transversal plane with emphasis on the apical region where most PCs develop. The sensitivity in detecting PCs for both techniques was calculated and correlated to the serum prostate–specific antigen (PSA) levels.
Results: A total of 72 PCs (25.7%) were diagnosed. We subsequently performed subgroup analysis depending on the serum PSA levels: in patients with a PSA of ≤10 ng/ml (n = 27) technique A has a PC sensitivity of 88.8% (p = 0.037) and technique B 96.2% (p = 0.326) as compared to our reference standard of 100% by sampling 12 biopsy cores in the same prostate. The number of positive biopsy cores using technique B was superior in 12 cases as compared to 3 cases with technique A (p = 0.04). In 12 patients the number of positive biopsy cores was identically. In patients with a PSA of >10 ng/ml (n = 45) technique A has a PC sensitivity of 93.3% (p = 0.083) and technique B 88.8% (p = 0.023) as compared to our reference standard. The number of positive core biopsies using technique A was superior in 14 cases as compared to 12 with technique B (p = 0.154). In 19 patients the number of positive biopsies was identical.
Conclusion: Our data suggest that in patients with PSA of ≤10 ng/ml technique B bring significant benefit with regard to the number of positive core biopsies, as well as an enhanced PC detection rate which is near the 12–core biopsy. Due to the fact that technique B samples more in the apical region where most cancers develop, it should be performed in suspected early stage cancers of the prostate (PSA≤10 ng/ml).