However, along with morphology, an immunohistochemical battery including HMB45, Melan-A, MDM2 and p16 are useful in distinguishing AML from WDLS/DDLS or lipoma.
Differential diagnosis of atypical lipomatous tumor/well-differentiated liposarcoma and dedifferentiated liposarcoma: utility of p16 in combination with MDM2 and CDK4 immunohistochemistry.
Overall, p16 immunostaining was positive in 3 LBs and in 12 out of 16 liposarcomas (10 WDL and 2 ML), with a sensitivity of 75%, a specificity of 90%, a positive predictive value of 80%, and a negative predictive value of 87%.
Four cases of dedifferentiated liposarcomas (DDLPS) and three cases of recurrent well-differentiated liposarcomas (WDLPS) were collected, and methylation status of p16INK4a gene promoter was analyzed using methylation-specific PCR (MSP) on DNA extracted from paraffin blocks. p16 expression was examined by immunohistochemistry on the same blocks.