TRANSLOCATION (X-18) IN A BIPHASIC SYNOVIAL SARCOMA WITH MORPHOLOGIC FEATURES OF NEURAL DIFFERENTIATION

The authors report a recurred neoplasm showing distinctive histologic, immunophenotypic, and ultrastructural features characteristic of biph asic synovial sarcoma with neural differentiation. The features includ e areas with a growth pattern of densely packed spindle cells in irreg ularly intersecting, broad fascicles, diffuse vimentin and HBA 71 immu noreactivity, expression of S-100 protein, and other neural markers. M oreover, areas with glandular structures and cellular expression of cy tokeratin and epithelial membrane antigen were noted. Additionally, a reas of neural-like growth pattern were positive for neuron-specific e nolase: HNK-1, and protein gene product 9.5. Furthermore, cytogenetic analysis, two-color interphase fluorescence in situ hybridization, and reverse transcription polymerase chain reaction demonstrated the reci procal translocation between chromosomes X and 18 associated with the different subtypes of turner cells. The establishment and characteriza tion of the tumor cell line are detailed, This cell line retains the d istinct morphologic and genetic characteristics of the original biphas ic synovial sarcoma with neural differentiation.