Abstrait

Pictorial review of imaging features of liposarcoma: local experience of regional hospital in Hong Kong

Sheung Yan LO

 Objective: A 10-year retrospective review of epidemiology and the imaging features of different subtypes of liposarcoma in

Material and methods: Data was retrieved from Radiological Information System (RIS) and PACS between January 2010 and July 2020 at United Christian Hospital.

Results: Twenty-six patients with liposarcoma were retrieved.  Eleven were male and sixteen were female. The mean age was 63.2 years old (ranged 22-86). The location of these cases shown as following. Thirteen cases found in retroperitoneum. Two cases noted in spermatic cord.

One case noted in groin and scrotum. Two upper limbs liposarcoma and nine lower limbs liposarcoma noted.The size of tumor ranges from 2.6cm to 20.2cm. Both found in retroperitoneum.

Subtypes include atypical lipomatous tumor/well differentiated, well differentiated with de-differentiation, de-differentiated, pleomorphic and myxoid. In well differentiated subtype, adipose tissue is predominant in imaging.

 In well differentiated with dedifferention subtype, it contains a focal nodular lipomatous region measuring more than 1cm. In some cases, non lipomatous component is predominant in the tumor. In myxoid liposarcoma subtype, it presents as a multilobulated intramuscular mass with high water content, which shows low T1W and high T2W signal. It also contains the adipose septation and shows diffuse contrast enhancement. 

In pleomorphic subtype, its imaging features show a well circuscribed mass containing small amount or absence of adipose tissue. Some also show internal hemorrhage or necrosis.

Conclusion:

Different subtypes of liposarcoma present wide range of imaging features in different imaging modalities. Recognition of abnormal fat in retroperitoneum and limbs are helpful for the diagnosis of liposarcoma.