The purposes of our study are to review and illustrate the imaging features of abdominal liposarcoma on CT and MR, based on a retrospective analysis of a series of patients from our institution.

Epidemiologic and Clinical FeaturesSarcomas constitute a heterogeneous group of rare solid tumors of mesenchymal cell origin with distinct clinical and pathological features, collectively accounting for approximately 1% of all adults malignancies and 15% of pediatric malignancies; they are usually divided into two broad categories:Sarcomas of soft tissues (including fat, muscle, nerve and nerve sheath, blood vessels, and other connective tissues); andSarcomas of bone.Soft tissue sarcomas are the most frequent sarcomas, with the majority (60%) arising in the extremities. Fifteen percent of all soft tissue sarcomas...

Correlating the histologic subtypes of abdominal liposarcoma with the radiologic findings presents a clinical challenge, as there are no specific imaging features across the spectrum of subtypes. In addition, it is often difficult to use imaging findings to diagnose abdominal liposarcoma when it lacks a fat component.Liposarcoma lesions sometimes include multiple histologic subtypes; thus variable CT attenuation or MR signal intensity may be found within the same lesion. Such histologic subtypes are usually classified on the basis of the most aggressive cellular component.The imaging findings...

Imaging plays a key role in the preoperative assessment of patients with liposarcoma, and a multi-imaging technique approach is usually necessary. CT and MR imaging can demonstrate important characteristics of these tumors and contribute to the obtainment of clinically significant information.As histologic subtypes affect the prognosis , a clear understanding of the varying imaging appearances should be helpful for diagnosis and for predicting the course of the disease in a patient with liposarcoma.

PEDRO OLIVEIRA DA SILVADepartment of RadiologyInstituto Português de Oncologia do Porto Francisco GentilRua Dr. António Bernardino de Almeida4200-072, [email protected]

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