Dynamic contrast enhanced MRI-derived parameters are potential biomarkers of therapeutic response in bladder carcinoma

Objectives To evaluate the performance of dynamic contrast enhanced (DCE) magnetic resonance (MR) imaging to assess the histological response after chemotherapy on bladder carcinoma. Methods From 2008 to 2010, 12 patients presenting localized urothelial carcinoma of the bladder were prospectively evaluated by DCE-MR imaging before and after two courses of cisplatin-based neoadjuvant chemotherapy. Size and thickness of tumours were measured. Relative enhancement at the arterial (rSI35s) and venous phases (rSI80s) of each tumour was obtained. Histological response was assessed and outcomes were recorded. Results Histological examination after neoadjuvant chemotherapy concluded as pathological complete response (pCR) for 6 out of 12 patients. Five patients developed recurrences (4/6 no pCR and 1/6 pCR). Significant differences, between before and after treatment, were found for patients with complete pathological response after chemotherapy for all MR quantitative values. Tumours decreased in size and thickness (both P = 0.03). After treatment, rSI80s was significantly different between pCR and non-pCR patients (P = 0.04) with a cut-off value of 40%. For this cut-off, sensitivity, specificity and accuracy were 83.33%. Similar recurrence free survivals were obtained if applying the MR cut-off value or the histopathological findings. Conclusion Our results suggest that DCE-MR imaging may be a useful biomarker for patients with localized bladder carcinoma, improving selection before surgery.