CT and MRI Diagnosis of Desmoid Type Fibromatoses

Objective:To investigate the CT and MRI findings of the desmoid fibromatoses and evaluating it's diagnosis value. Methods:Clinical features and image characteristics of 16 patients with DF proved pathologically were analyzed retrospectively. Seven of the 16 cases underwent CT plain scan and enhancements and 7 cases underwent MRI plain scan and enhancements, of which 2 cases underwent both of them. Results:16 cases of DF were single, extra-abdominal type was seen in 7, abdominal wall type in 5 and intra-abdominal type in 4 tumors. Unclear border was seen in 14 cases and clear border in 2 cases. There were 13 cases with invasive growth and 3 cases with expansive growth. The lesion was parallel to the long axis of the muscle in 9 cases. CT manifestations:9 cases showed slightly lower density on plain scan, and no bleeding, necrosis and calcification were seen in lesions. The intratumoral ribbon-like enhancement was seen in 7 cases, and the progressive and continuous enhancement was seen in 6 cases with delayed scan. MRI manifestations:9 cases showed low signal intensity bands on lipid-suppressing T2 WI, and no bleeding or necrosis were seen. All cases showed obvious uneven enhancement and continuous enhancement with delayed scan. "Crab foot-like" infiltrated the surrounding tissue was seen in 5 cases, "fascial tail sign" in 4 cases. Conclusion:DF has certain characteristics on CT and MRI, and comprehensive analysis of them is of great value to its diagnosis and differential diagnosis. CT and MRI can clearly assess the margin and extent of DF, and help to make a plan before surgery.