CHRNA6 RNA in situ hybridization is a useful tool for the diagnosis of extraskeletal myxoid chondrosarcoma. (PubMed, Mod Pathol)
All examined cases of histological mimics were negative for CHRNA6 overexpression; however, limited CHRNA6 expression, not reaching a threshold of greater than 5 puncta or one aggregate of chromogen in more than 25% of cells, was observed in 69 of 685 mimics (10.1%), spanning an array of mesenchymal tumors. Taken together, these findings suggest that, with careful interpretation and the use of appropriate thresholds, CHRNA6 RNA CISH is a potentially useful ancillary histological tool for the diagnosis of EMC.