Diffusion-weighted magnetic resonance imaging in patients selected for radical cystectomy: detection rate of pelvic lymph node metastases

Abstract

Objective: To evaluate whether DW-MRI improves the detection of pelvic lymph nodes metastates in patients with bladder cancer undergoing radical cystectomy.

Patients and methods: 36 patients with CT scan negative for nodal metastates underwent DW-MRI before surgery. Diagnostic accuracy of DW-MRI was compared with histopathological findings.

Results: Mean ADC value was 0.85 × 10(-3) mm(3)/s in the nodal metastatic group and 1 × 10(-3) mm(3)/s in the nodal non-metastatic group (P = 0.02). The ADC cut-off value, obtained by the ROC curve was 0.86 × 10(-3) mm(3)/s. Patient-based sensitivity, specificity and positive and negative predictive values were 76.4%, 89.4%, 26.6%, and 71.4%, respectively.

Conclusion: DW-MRI may be used to differentiate metastatic from non-metastatic lymph nodes in patients with high-grade bladder cancer.