Straub BK, et al. - Since the use of perilipins as markers for soft tissue tumor differential diagnosis has only been studied in a few instances, researchers examined assessed 478 human soft tissue tumors and 60 normal tissues for perilipin expression. In all observed cases of well-differentiated liposarcomas, >90% of myxoid round cell liposarcomas, and >70% of pleomorphic liposarcomas, perilipin 1 was immunohistochemically positive. Only the differentiated components of dedifferentiated liposarcomas were immunohistochemically positive for perilipin 1, while all other types of soft tissue sarcomas were negative for perilipin 1. In dedifferentiated and pleomorphic liposarcomas and almost all other high-grade sarcomas, perilipin 2 was more prominent. Perilipin 2 was practically nonexistant in well-differentiated liposarcomas, lipomas, or normal adipose tissue. The authors concluded that perilipin 1 could be a marker for the differential diagnosis of liposarcomas from other soft tissue sarcomas, and perilipin 2 is negatively correlated with tumor grade and may be helpful for therapy.