PROSTATE BIOPSY OUTCOME – COMPARISON OF SINGLE- AND BI-PLANE TRANSRECTAL SONOGRAPHY

Purpose: Transrectal biopsy of the prostate under the guidance of ultrasonography is the mainstay of the diagnostic evaluation of prostate cancer (PC). Aim of our study is the comparison of biopsy done by the conventional ultrasound probe with one imaging plane (1st group) and by the probe with biplane imaging (2nd group).

Methods and Materials: In the retrospective study we evaluated patients after the primary sonographically guided transrectal prostate biopsy. Evaluation was performed on the imaging system HAWK 2102 (BK-Medical, Denmark) with the conventional single-plane probe (BK 8551) or the bi-plane probe (BK 8808). Prostate size, presence of the lesions detectable by ultrasound, histopathological findings (including number of inconclusive cores), complications and number of missed specimens was compared. In all patients we performed topographic biopsy of the peripheral zone which allows identification of the location and spread of the specimens in the prostate.

Results: Transrectal biopsy was performed in 237 patients (128 patients by the single-plane probe –1st group, 109 patients by the bi-plane probe –2nd group). Average PSA in the time of biopsy and volume of the prostate did not differ signifficantly in both groups. Visible lesions were detected in 41 (17%) patients and prostate carcinoma was confirmed in 18 patients in this group. In the prostate volume under 40ml (6 cores biopsy) we detected PC in 44 (34%) patients in the first group and in 41 (38%) patients the second group. Patients with higher prostate volume (>6 cores biopsy) had lower incidence of positive cores –35 (27%) patients in the 1st group and 28 (26%) patients in the 2nd group, respectively. Complications (urine retention, fever >38°C, hematuria or bleeding from rectum after 12 hours) occured in 6% of patients in the 1st group and in 3.2% of patients in the 2nd group. Number of inconclusive cores (cores located behind the prostate or cores that pathologist cannot evaluate properly) was in 5.4% of patients in the 1st group and in 2.9% of patients in the 2nd group, respectively.

Conclusions: We achieved the similar outcome in the diagnosis of PC when using single- and bi-plane probe in transrectal biopsy of the prostate. Incidence of complications and occurence of inconclusive cores was lower when we used bi-plane probe which can be explained by better visualisation and overall orientation during the biopsy.