[Determining the depth of infiltration in urinary bladder carcinoma with contrast medium enhanced dynamic magnetic resonance tomography. With reference to postoperative findings and inflammation].

OBJECTIVE

The purpose of this study was to evaluate dynamic contrast-enhanced magnetic resonance imaging for the staging of urothelial bladder carcinoma and to compare it with plain and contrast-enhanced spin-echo MRI.

METHODS

Pre-operative MRI was carried out in 62 patients. Post-operative histological examination confirmed bladder carcinoma in 50/62 patients. Carcinoma was excluded in 12 patients. Beside spinecho MRI a dynamic contrast-enhanced study was performed immediately after IV application of Gd-DTPA using 10 sequential FLASH-2Dsequences, each with a duration of 15 s. Images were evaluated visually by three radiologists in a blinded fashion.

RESULTS

In 41/62 patients pre-operative tumor staging with the dynamic contrast-enhanced study was confirmed by the histological examination after surgery. MRI with spinecho sequences yielded correct staging in 30/62 patients (P = 0.028). Staging of superficial bladder cancer was more accurate with dynamic contrast-enhanced MRI than with conventional MRI (P = 0.024). Overstaging was observed in some patients with stage pT1 tumors. Furthermore, postoperative changes of the bladder wall could be differentiated from cancer due to significantly earlier contrast enhancement of bladder cancer compared with postoperative and inflammatory alterations (P < 0.001).

CONCLUSION

Contrast-enhanced dynamic MRI is a helpful addition in the presurgical T-staging of bladder cancer.