Comparison of classical transrectal prostate biopsy versus cognitive registration in rebiopsy

INTRODUCTION

The aim of this study is to compare performance of two biopsy approaches in patients with at least one previous negative prostate biopsy (PB): classical transrectal biopsy (ClTB) versus cognitive registration biopsy (COG-TB).

MATERIAL AND METHODS

A retrospective study of 205 patients with at least one negative PB. 144 (70.2%) patients underwent a prior mpMRI and 61 (29.8%) patients did not. Nodule classification was carried out according PI-RADS version 2. Peripheral zone (PZ) grouped pZa, pZpl and pZpm areas, transition zone (TZ) Tza, Tzp and Cz areas, and anterior zone (AZ) AS areas. COG-TB was conducted in patients with previous mpMRI (144); while in the remaining 61 (29.8%) patients a ClTB of PZ and TZ was performed. Statistical analysis was performed using Chi square and T-student tests for qualitative and quantitative variables, respectively. Multivariate analysis was carried out in order to identify predictive variables of prostate cancer.

RESULTS

Median patient age was 68 (IQR 62-72) years, median PSA was 8.3 (IQR 6.2-11.7) ng/ml and median previous biopsies was 1 (IQR 1-2). Digital rectal examinations (DRE) findings were normal in 169 (82.4%) patients and suspicious in 36 (17.6%) patients (cT2a-b in 34 patients and cT2c in 2). Median prostate volume was 48 (IQR 38-65) cc. Statistically significant differences in PSAD between both groups were found (P=.03). Transrectal ultrasound (TRUS) showed hypoechoic nodules in 8 (13.1%) ClTB patients and in 62 (43.1%) COG-TB patients (P=.0001). The median number of biopsy cylinders per set of prostate biopsies was 10 (IQR 10-10) in ClTB group and 11 (IQR 9-13) in COG-TB group (P=.75). Cancer was diagnosed in 74 (36.1%) patients: of them, 10 (16.4%) were ClTB patients and 64 (44.4%) COG-TB (P=.0001). Tumors classification was as follow: ISUP-1: 34 (45.9%), ISUP-2: 21 (28.4%), ISUP-3: 9 (12.2%), ISUP-4: 7 (9.5%) and ISUP-5: 3 (4.1%). No significant statistical differences were found (P=.89). The median number of biopsy cylinders impaired per set of prostate biopsies was 1 (IQR 1-5) in ClTB group and 2 (IQR 1-4) in COG-TB group (P=.93). Regarding independent predictive variables for prostate cancer the results were: age (OR=12.05; P=.049), suspicious DRE (OR=2.64; P=.04), hypoechoic nodule (OR=2.20; P=.03) and mpMRI +COG-TB sequence (OR=3.49; P=.003).

CONCLUSIONS

In patients with at least one negative PB, mpMRI +COG-TB sequence improves 3.5 (OR=3.49) times the diagnosis prostate vs. ClTB.

Effectiveness of the «cognitive» biopsy in the diagnosis of prostate cancer in patients with a previous negative biopsy

INTRODUCTION

Evaluation of the effectiveness of cognitive biopsy (CB) in patients with clinical suspicion of prostate cancer (PC), and at least one negative biopsy (TRB).

MATERIAL AND METHOD

Retrospective study of 144 patients with at least one previous TRB and magnetic resonance imaging (MRI). The MRI nodules were classified based on PI-RADS v2 grouping pZa, pZpl and pZpm as the peripheral zone(PZ), Tza, Tzp and CZ as the transitional zone (TZ), and the AS zones as the anterior zone (AZ). A biopsy was indicated for nodules ≥PI-RADS 3. Uni and multivariate analysis was undertaken (logistic regression) to identify variables relating to a PI-RADS 3 tumour on biopsy.

RESULTS

The median age was 67 (IQR: 62-72) years, the median PSA was 8.2 (IQR: 6.2-12) ng/ml. A nodule was identified on MRI in the PZ in 97 (67.4%) cases, in the TZ in 29 (20.1%), and in the AZ in 41 (28.5%). PC was diagnosed on biopsy in 64 (44%) patients. The cancer rate in the PI-RADS 3 lesions was 17.5% (7/40), in the PI-RADS 4 47.3% (35/73), and in the PI-RADS 5 lesions it was 73.3% (22/29) (p=.0001). Multivariable analysis with variables that could influence the biopsy result in patients with PI-RADS 3: None (age, PSA, number of previous biopsies, rectal examination, PSAD, prostate volume or number of extracted cylinders) behaved as an independent tumour predictor.

CONCLUSIONS

The diagnostic performance of CB in patients with at least one previous negative biopsy was 44%, increasing according to the PI-RADS grade, and low in PI-RADS 3. No clinical variable predictive of cancer was found in patients with PI-RADS 3.