[Imaging features of nonepithelial tumors of the bladder].

Objective: To summarize the imaging features of nonepithelial tumors of the bladder.

Methods: The Imaging findings in 20 surgically treated patients with pathologically proved nonepithelial tumors of the bladder were retrospectively analyzed. The tumors included leiomyoma (n = 9), pheochromocytoma (n = 6), leiomyosarcoma (n = 2), rhabdomyosarcoma (n = 1), carcinosarcoma (n = 1), inflammatory myofibroblastoma (n = 1).

Results: The leiomyomas were round or ellipse in shape with a sharp border and homogeneous density, and showed a low signal intensity on T1WI and T2WI in 1/1 case; slight enhancement on CT after contrast enhancement in 6/7 cases; and a poor blood supply on color Doppler ultrasonography in 3/4 cases. The pheochromocytoma had a round or oval shape and clear border, and slightly lobulated in 4/6 cases, homogeneous density/echo/signal in 5/6 cases, calcification in 1 case, low signal intensity on T1WI and high signal intensity on T2WI in 1/1 case, moderate or marked enhancement on CT and MRI in 4/5 cases, and strong blood supply on color Doppler ultrasonography in 3/4 cases. The inflammatory myofibroblastoma showed the same imaging features as the pheochromocytomas. Other malignant tumors showed an irregular configuration, with a poorly defined border, heterogeneous density/echo/signal and moderate to strong enhancement on CT.

Conclusion: Most leiomyomas and pheochromocytomas of the bladder show some typical imaging features on CT, MRI and ultrasound, which are helpful in making correct diagnosis and treatment plan preoperatively. Other malignant nonepithelial bladder tumors do not show special imaging characteristics and can only be diagnosed qualitatively.