What’s next for VI-RADS? Updates and future perspectives from the ACR VI-RADS steering committee

Figures

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  Fig. 1. Dynamic contrast-enhanced (DCE) MRI improving prediction of non-muscle-invasive bladder cancer in 78-year-old man. (A) T2-weighted imaging, (B) diffusion-weighted imaging, and (C) apparent diffusion coefficient map show a broad-based polypoid mass (arrow) in the left posterolateral bladder wall measuring 1.4 × 1.4 cm. No stalk or thickened inner layer is present and there is a smooth interface between tumor and the muscle layer. (D) Dynamic contrast-enhanced MRI shows a delayed enhancing stalk (arrowhead) consistent with a DCE category 2. VI-RADS score would be 3 based on biparametric MRI and 2 based on multiparametric MRI. Transurethral resection revealed non-muscle-invasive bladder cancer

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  Fig. 2. Tumor contact length used in conjunction with VI-RADS to correctly identify non-muscle-invasive bladder tumor in 77-year-old man. (A) T2-weighted imaging, (B) diffusion-weighted imaging, (C) apparent diffusion coefficient map, and (D) dynamic contrast-enhanced MRI show 1.7 × 0.9 cm polypoid tumor with broad base (arrow) at the left posterolateral wall. No stalk or thickened inner layer is seen resulting in a VI-RADS score of 3. (A) Tumor contact length measured on (A) T2-weighted imaging is 1.6 cm, less than several proposed cutoffs (e.g., 2.0 cm, 2.5 cm, 3.0 cm) for differentiating muscle-invasive and non-muscle-invasive bladder tumors. Transurethral resection revealed non-muscle-invasive bladder cancer

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  Fig. 3. 74-year-old man with intradiverticular bladder tumor illustrating difficulty of applying VI-RADS. (A) T2-weighted imaging demonstrates 3.1 × 2.5 cm tumor (*) with intermediate T2 signal occupying right posterolateral bladder diverticulum (arrowheads). (B) Tumor (*) shows marked degree of restricted diffusion on diffusion-weighted imaging. There is loss of normal T2 dark signal bladder wall with irregular margin with the perivesical fat (arrow). As there is no “muscularis propria” layer in bladder diverticula, this represents a direct jump from non-muscle-invasive bladder tumor to extravesical extension. Despite resection and chemotherapy, patient died from progression of disease (not shown) after 2 years

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  Fig. 4. Bladder MRI of 68-year-old man demonstrating optimal quality allowing detailed morphological assessment of subcentimeter bladder tumor. (A) T2-weighted imaging, (B) diffusion-weighted imaging, (C) apparent diffusion coefficient map, and (D) dynamic contrast-enhanced MRI shows 0.7 cm polypoid tumor (arrow) at left lateral bladder wall which demonstrates restricted diffusion and avid enhancement. In contrast, the thickened inner layer (arrowhead) shows distinct imaging features from the tumor itself with (A) high T2 signal, (B-C) lack of restricted diffusion, and (D) minimal enhancement. Note that the quality of the multiparametric MRI is “optimal” as there is high signal-to-noise ratio, anatomical landmarks are clearly visualized, and there are no imaging artifacts. Transurethral resection revealed non-muscle-invasive bladder cancer

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  Fig. 5. Application of nacVI-RADS before and after neoadjuvant chemotherapy for muscle-invasive bladder cancer in 68-year-old man. (A-C) Pre-treatment MRI; (A) T2-weighted imaging, (B) diffusion-weighted imaging, and (C) dynamic contrast-enhanced MRI shows 4.6 × 1.3 cm bladder tumor (arrow) diffusely involving muscularis propria of the left and posterior bladder wall (VI-RADS 4). (D-F) Post-treatment MRI; After neoadjuvant chemotherapy, (D) T2-weighted imaging, (E) diffusion-weighted imaging, and (F) dynamic contrast enhancement imaging show decrease in size of tumor (arrow) to 3.4 × 1.2 cm but persistent muscle invasion (i.e., lack of downstaging). Therefore, response to neoadjuvant therapy is categorized as nacVI-RADS 5. Radical cystectomy revealed deep muscularis propria involvement and perivesical soft tissue infiltration (ypT3)

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  Fig. 6. Persistent muscle-invasive bladder cancer after neoadjuvant chemotherapy in 69-year-old man without pre-treatment MRI. (A) T2-weighted imaging, (B) diffusion-weighted imaging, (C) apparent diffusion coefficient map, and (D) dynamic contrast-enhanced MRI shows 3.9 × 2.7 cm mass (arrow) at left posterolateral bladder wall with diffuse invasion of muscularis propria and extension into perivesical fat (arrowheads). While no pre-treatment MRI was available, it is clear from this single timepoint imaging that there was a suboptimal response to neoadjuvant chemotherapy. Cystectomy revealed residual muscle invasive bladder cancer with perivesical soft tissue infiltration (ypT3)