Keywords:
Oncology, Pelvis, Genital / Reproductive system male, MR, Staging, Diagnostic procedure, Imaging sequences, Neoplasia
Authors:
B. Yagci, F. Ufuk, E. Sağtaş, P. Cakmak, D. HEREK, A. E. Zumrutbas, N. Sen Turk; Denizli/TR
DOI:
10.1594/ecr2018/C-0800
Methods and materials
The local institutional review board approved this retrospective study.
The study population was drawn from 1184 consecutive patients who underwent mpMRI between January 2015 and September 2017.
A total of 69 patients who underwent radical prostatectomy for clinically localized or locally advanced prostate cancer were enrolled in this single-center study.
No patient had a prior therapy for prostate cancer.
All mpMRI examinations were performed with a 1.5 T MRI system (Ingenia,
Philips Healthcare,
Best,
The Netherlands) using a 32-channel torso coil.
All mpMRI parameters were designed according to the technical specifications in the PI-RADS v2 document.
The in-plane dimension for high resolution T2W images was 0.6 mm (phase) x 0.4 mm (frequency).
b value was 1800 sec/mm2 in diffusion‐weighted imaging.
Temporal resolution was 7 seconds in dynamic contrast-enhanced imaging.
All MRI images were evaluated on the workstation (Extended MR WorkSpace,
Philips Medical Systems) by an experienced radiologist in reading mpMRI.
The presence of ECE was evaluated by an experienced radiologist according to the following ECE criteria in the PI-RADS v2 document: an irregular or spiculated margin,
asymmetry or invasion of the neurovascular bundles,
a bulging prostatic contour,
obliteration of the rectoprostatic angle,
breach of the capsule with direct tumor extension or bladder wall invasion,
and a tumor-capsule contact length greater than 10 mm [4].
The presence of any of these imaging features was considered as positive for extracapsular extension in mpMRI.
Preoperative biopsy Gleason scores and serum PSA values were available in all patients.
The volume of the prostate gland was calculated on T2W images with following formula: maximum AP diameter x maximum transverse diameter x maximum longitudinal diameter x 0.52.
PSA density was calculated by dividing total serum PSA by total prostate volume.
A preoperative biopsy Gleason score equal or greater than 7 and a PSA density equal or greater than 0.20 were accepted as positive risk factors for ECE.
Radical prostatectomy specimens were evaluated by an experienced uropathologist.
Statistical analyses were obtained using the chi-square test.
P < 0.05 was considered to indicate a statistically significant difference.