radiological and histopathological comparison of giant cell lipomas and atypical lipomatous tumors (ALT)/well differentiated liposarcomas (WDL)

Objective: The aim of this study is to make histological comparison between atypical lipomatous tumors (ALT)/well differentiated liposarcomas (WDL) and giant cell lipomas. Design: Retrospective study Setting: Istanbul Goztepe Prof. Dr. Suleyman Yalcin City Hospital Orthopaedics and Pathology Clinic Subjects: Forty-five patients diagnosed with "giant cell lipomas or "atypical lipomatous tumors (ALT)/well differentiated liposarcomas (WDL)" Intervention: The patients were assessed in terms of their histological and radiological features. Main outcome measure: Radiological findings were able to discriminate the ALT/WDL from giant cell lipomas results. Results: On T2 weighted MRI, septal structures were found in 15 out of 16 cases (93.8%) of ALT/WDL, whereas 12 out of 29 cases (41.4%) of lipoma displayed septa >2 mm (P<0.01). Septal contrast enhancement in ALT/WDL was statistically significant compared to lipoma group (P<0.01). For ALT/ WDS, 13 of the 16 (81.3%) tumors were localized in the lower extremity (P<0.05). For less than 75% fat component in magnetic resonance imaging (MRI), ALT/WDL group displayed statistically significant difference in comparison with lipoma group. Conclusion: Based on the results of our study, the imaging findings can be used to provide differential diagnoses and a plan for proper management. This is the first study to differentiate the ALT/WDL from giant cell lipomas based upon the MRI findings to assist conventional histopathological examination and it can be used as a base for further future researches.