Detection of Myxoid Liposarcoma

Liposarcoma is the most common sarcoma and makes about 20% of all soft tissue sarcomas. According to the WHO classification, liposarcoma is divided into four major types based on morphological features, cytogenetic properties and clinical behavior and includes the following entities  

Well differentiated liposarcoma (atypical lipoma or atypical lipomatous tumor) 

The t(12 16)(ql3 pll) translocation is the most common translocation, described in more than 90% of myxoid and round cell liposarcoma, mainly those arising within the thigh soft tissue. Myxoid liposarcoma arising elsewhere seems to be not related to this specific genetic abnormality. The t(12 16)(ql3 pll) translocation is caused by the fusion of the TLS gene and the CHOP gene. 

Some studies show that there is no significant association between the fusion variant and the tumor behavior but other studies reported that the poorly differentiated round cell type of myxoid liposarcoma is mainly associated with the fusion transcript type 1. 

As the two above-described translocations are specific for myxoid and round cell liposarcoma, they can be used as sensitive molecular markers to distinguish both liposarcoma types from other neoplastic or nonneoplastic lesions with similar morphologic features. This method can be also used for the examination of surgical margins after surgical resection or for the detection of micrometastases. Additionally, 

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