Desmoplastic small round cell tumor: imaging findings associated with clinicopathologic features

To describe imaging findings of desmoplastic small round cell tumor (DSCRT) and to clarify the relation between radiologic appearances and clinicopathologic features.

CT scans and MRI examinations of four male patients with histologically confirmed DSCRT (mean age = 20 years) were retrospectively analyzed.

The common imaging finding was multiple peritoneal masses with regular contour situated within mesentery. Tumors showed central low attenuation in 75% of patients on nonenhanced CT. All tumors showed inhomogeneous enhancement on CT. Small foci of punctate calcification were identified in a part of the tumor in all patients. Bone metastases were identified on enhanced CT in two patients 2 and 8 months after diagnosis, respectively. Pleural dissemination was identified in all patients, and one patient had double-sided dissemination. T2-weighted MRI showed inhomogeneous high signal intensity, and small cysts were identified in two patients. Fluid-fluid levels were identified in six tumors on T2-weighted images, which suggested the presence of hemorrhage. Tumors had inhomogeneous signal intensity low or isointense relative to skeletal muscle on T1-weighted images. Two lesions exhibited inhomogeneous enhancement with central low intensity consistent with necrosis.

Imaging studies can depict disseminated characteristics and disease extent during the clinical course of DSRCT.