Interobserver agreement of PI‐RADS v. 2 lexicon among radiologists with different levels of experience

Abstract

Background Evaluation of interobserver agreement of the PI‐RADS v2 lexicon is important to validate the uniformity of this widely used classification. Purpose To determine the interobserver agreement of PI‐RADS v2 lexicon among eight radiologists with varying levels of experience. Study Type Retrospective. Population In all, 160 consecutively imaged men with confirmatory targeted biopsy. Field Strength/Sequence 3T scanner without an endorectal coil. T2‐weighted imaging (T2w), diffusion‐weighted imaging (DWI), apparent diffusion coefficient (ADC) map and dynamic contrast‐enhanced sequence were performed. Assessment Eight radiologists (two highly experienced, two moderately experienced, and four less experienced) independently read 130 lesions in the peripheral zone (PZ) and 30 lesions in the transition zone (TZ), blinded to clinical MRI indication and biopsy results. The features described in PI‐RADS v2 for TZ and PZ lesions were evaluated. Statistical Tests Conger's kappa, percentage of concordance, and first‐order agreement coefficient (AC1) were used to evaluate interobserver agreement. Results From the features evaluated on PZ lesions, definite extraprostatic extension (EPE) / invasive behavior on T2w had good agreement (AC1 = 0.80), and the others had fair agreement (AC1 = 0.32–0.40). From the features evaluated on TZ lesions, two had good agreement: definite EPE/invasive behavior (AC1 = 0.77) and moderate/marked hypointensity (AC1 = 0.67) on T2w. Encapsulation and lenticular shape on T2w, focal (not indistinct) on DWI and ADC map, and marked hypointensity on ADC map (AC1 = 0.45 to 0.60) had moderate agreement, whereas heterogeneous and circumscribed (not obscured margins) on T2w, marked hyperintensity on high‐b‐value DWI, and the presence or not of early enhancement in the lesion/region of the lesion (AC1 = 0.30 to 0.38) had fair agreement. Data Conclusion Interobserver agreement in PI‐RADS v2 lexicon ranges from fair to good among radiologists and improves with increasing experience. Level of Evidence: 2 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2020;51:593–602.

A Comparative Study of Prostate Cancer Detection Rate Between Transperineal COG-TB and Transperineal FUS-TB in Patients with PSA ≤20 ng/mL

“…7 All MRI scans were performed at 3.0 T with axial T1-weighted images (T1WI), multiplane (Axial, coronal, and sagittal) T2-weighted images (T2WI), and axial diffusion weighted imaging (DWI) (measured b-values of 0.400 and 800 seconds/mm 2 , calculated b-value of 2000 seconds/mm 2 ), but without dynamic contrast enhancement (DCE). 8 The prostate nodules found by bpMRI were evaluated by PI-RADS V2 scores by the deputy chief or senior physicians. 9 The lesions were located in detail before the puncture (lesions' position, diameter, distance from the bladder neck, and distance from the dorsal margin of the prostate).…”

Interobserver Agreement of PI‐RADS v. 2: Not All Features or Observers Are Created Equal

“…Nevertheless, the results of Mussi et al support other studies that have shown improved intrareader agreement and interreader agreement for PI‐RADSv2 scoring with increasing radiologist experience . When assessing individual imaging features, Mussi et al showed the best agreement for observation size, focality, and signal intensity on DWI in the PZ and observation size, signal intensity on DWI, and encapsulated nature in the TZ similar to Rosenkrantz et al…”

“…In this issue of The Journal of Magnetic Resonance Imaging, Mussi et al sought to answer this question by comparing interobserver agreement levels across a group of eight radiologists with varying experience in prostate MRI when applying PI-RADSv2. 4 The authors of the present study used a very similar methodology to Rosenkrantz et al, 3 namely, radiologists evaluated PI-RADSv2 scoring and individual imaging features in a preselected population of 160 men encompassing a representative number of PZ and TZ observations (130:30 split). Radiologists were provided with the location of observations that had histopathology verified by targeted fusion biopsy.…”

Interobserver agreement of Prostate Imaging–Reporting and Data System (PI-RADS–v2)

“…The main target is to build acceptable technical standards for prostate mp-MRI, which makes it clear and simpler with subsequent standardized reporting terms, as well as help the procedure of MRI-guided biopsy. It also develops assessment groups that summarize ranks of the risk that could be helpful to choose and prepare patients for the next steps in management and finally enhance interdisciplinary communications with physicians [6,[9][10][11][12][13][14][15][16][17][18][19]. Having both targeted and systematic biopsy could offer the peak discovery of clinically significant prostate cancer [20][21][22][23][24][25][26][27].…”

“…Numerous MRI-guided sampling procedures will enhance the recognition of clinically significant PCa as well as decrease the discovery of insignificant cancer decreasing the unnecessary costly treatments and their possible complications [27]. Many studies discussed the interobserver agreement of PI-RADS-v2 in the assessment and discovery of prostate cancer [13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31]. The uniqueness of our study is the assessment of interobserver in the peripheral zone (PZ) and the central zone (CZ) separately, as well as the interobserver agreement of the different pulse sequences of PI-RADS-v2.…”