Audit of cancer yields after prostate MRI using both the PI-RADS version 2 and Likert scoring systems.

AIM: To audit diagnostic yields of the updated magnetic resonance imaging (MRI)-directed prostate cancer diagnostic service according to Prostate Imaging - Reporting and Data System (PI-RADS) version 2 and Likert assessments, comparing outcomes of the two scoring systems. MATERIALS AND METHODS: Consecutive men with suspected cancer undergoing prostate MRI were included. Biopsy rates and histological diagnostic yields of all and International Society of Urological Pathology Grade Group (ISUP GG) ≥2 cancers according to PI-RADS and Likert assessment categories were documented and outcomes compared. RESULTS: Of 326 men (91% biopsy naive), 177 (54%) underwent transrectal (n=119) or transperineal (n=58) ultrasound-guided biopsies; 92% with negative MRI avoided immediate biopsies following multidisciplinary team (MDT) review. All cancer and ISUP GG ≥ 2 cancer-detection rates increased with increasing suspicion scores. Prospective paired PI-RADS and Likert scoring was undertaken in 323/326 studies, with 87% concordance rate. High concordance between PI-RADS and Likert scores was observed in negative MRI (99%) and score 5 (96%). High discordance was demonstrated in the PI-RADS 4 group (32% with PI-RADS 4 categories up-risked to Likert 5). All cancer and ISUP GG ≥ 2 cancer detection rates for MRI score ≥3 were 78% and 63%, and for MRI score ≥4 were 75% and 61%, respectively for both PI-RADS and Likert scoring systems. CONCLUSIONS: Most men with negative prostate MRI can avoid immediate biopsies following MDT review. Performance of PI-RADS and Likert scoring systems in clinically significant cancer detection after positive MRI is equivalent. Discordance between PI-RADS and Likert systems seems mostly confined to PI-RADS 4 categories.

Diagnostic yields in patients with suspected prostate cancer undergoing MRI as the first-line investigation in routine practice.

AIM: To document cancer yields of magnetic resonance imaging (MRI)-directed biopsies in men with suspected prostate cancer referred to secondary care. MATERIALS AND METHODS: Men with suspected cancer undergoing multiparametric prostate MRI as the first-line investigation were included in the present study. Systematic transrectal prostate biopsies with/without cognitive targeted biopsies were performed. Diagnostic yields of International Society of Urological Pathology (ISUP) ≥2 cancers by the Prostate Imaging Reporting and Data System (PI-RADS) category were recorded. Impacts of prostate-specific antigen (PSA) density on biopsy results and yields of non-targeted biopsies in MRI non-suspicious prostate sextants assessed. RESULTS: Of 262 men (90.5% biopsy naive), 86 (33%) MRI examinations were negative (PI-RADS 1-2) and 176 (67%) positive (PI-RADS 3: 8%; PI-RADS 4: 21%; PI-RADS 5: 38%). Two hundred and thirteen of 262 patients underwent a biopsy. ISUP ≥2 cancer detection rates were 8% (5/61) for PI-RADS 1-2, 18% (3/17) for PI-RADS 3, 49% (22/45) for PI-RADS 4, and 80% (72/90) for PI-RADS 5. Proportions of ISUP ≥2 increased with higher PSA densities in positive patients (%ISUP ≥2 for PSA density groups <0.12, 0.12 to <0.15 and ≥ 0.15 was 0%, 0%, 25% for PI-RADS 3, 21%, 33%, 68% for PI-RADS 4 and 40%, 83%, 89% for PI-RADS 5 respectively). ISUP ≥2 cancers were twice as likely in tumour adjacent sextants (52% versus 24%), without upgrading of gland level histology from insignificant to clinically significant prostate cancer by the sampling of normal-appearing tumour non-adjacent sextants. CONCLUSIONS: One third of men can avoid biopsy after negative MRI. Cancer detection rates increase with PSA density values within positive MRI suspicion categories. Sampling normal-appearing tumour non-adjacent sextants may be unnecessary for whole-gland therapy.

Stage T3a renal cell carcinoma: staging accuracy of CT for sinus fat, perinephric fat or renal vein invasion.

OBJECTIVE: To study the accuracy of CT for staging T3a (TNM 2009) renal cell carcinoma (RCC). METHODS: Unenhanced and nephrographic phase CT studies of 117 patients (male:female = 82:35; age range, 21-86 years) with T1-T3a RCC were independently reviewed by 2 readers. The presence of sinus or perinephric fat, or renal vein invasion and tumour characteristics were noted. RESULTS: Median (range) tumour size was 5.5 (0.9-19.0) cm; and 46 (39%), 16 (14%) and 55 (47%) tumours were pT1, pT2 and pT3a RCC, respectively. The sensitivity/specificity for sinus fat, perinephric fat and renal vein invasion were 71/79%, 83/76% and 59/93% (Reader 1) and 88/71%, 68/72% and 69/91% (Reader 2) with κ = 0.41, 0.43 and 0.61, respectively. Sinus fat invasion was seen in 47/55 (85%) cases with T3a RCC vs 16/55 (29%) and 33/55 (60%) for perinephric fat and renal vein invasion. Tumour necrosis, irregularity of tumour edge and direct tumour contact with perirenal fascia or sinus fat increased the odds of local invasion [odds ratio (OR), 2.5-3.7; p < 0.05; κ = 0.42-0.61]. Stage T3a tumours were centrally located (OR, 3.9; p = 0.0009). CONCLUSION: Stage T3a RCC was identified with a sensitivity of 59-88% and specificity of 71-93% (κ = 0.41-0.61). Sinus fat invasion was the most common invasive feature. ADVANCES IN KNOWLEDGE: Centrally situated renal tumours with an irregular tumour edge, inseparable from sinus structures or the perirenal fascia and CT features of tumour necrosis should alert the reader to the possibility of Stage T3a RCC (OR, 2.5-3.9).

Bladder cancer: evaluation of staging accuracy using dynamic MRI.

AIM: To assess the accuracy of magnetic resonance imaging (MRI) in staging bladder cancer and to assess whether dynamic gadolinium-enhanced sequences have any added benefit in staging. MATERIALS AND METHODS: Over a 22 month period, the MRI findings of 100 consecutive patients with histologically proven transitional cell carcinoma (TCC) of the bladder were reviewed. The T stage was assessed independently on T2-weighted imaging alone and in combination with gadolinium-enhanced MRI. The final histological diagnosis was considered the reference standard. Statistical analysis was performed to ascertain stage-by-stage accuracy. Accuracy of MRI in differentiating superficial (≤ T1) from invasive (≥ T2) and in differentiating organ-confined (≤ T2) from non-organ-confined (≥ T3) disease was assessed. RESULTS: On a stage-by-stage basis, tumours were correctly staged using MRI in 63% of patients (observed agreement=0.63, weighted kappa=0.57). The sensitivity and specificity of MRI to differentiate between superficial (≤ T1) from invasive (≥ T2) disease was 78.2 and 93.3%. The observed agreement for this group was 85% (kappa=70%; p<0.0001). The sensitivity and specificity of MRI to differentiate between organ-confined (≤ T2) from non-organ confined (≥ T3) disease was 90.5 and 60%. The observed agreement for this group was 89% (kappa=30%; p<0.01). Gadolinium-enhanced images improved staging in only three patients. CONCLUSION: In the present study MRI was found to be a moderately accurate tool in assessing the T stage. Agreement on a stage-by-stage basis was good. Agreement for differentiating between non-invasive versus muscle-invasive disease was good and that for organ-confined versus non-organ-confined disease was fair. Routine use of gadolinium-enhanced images is not routinely required.