INSM1 and synovial sarcoma: Although our case study showed the expression of neuroendocrine markers, such as CD56 and INSM1, with negativity for cytokeratin, NUT, desmin, and SS18-SSX, the retention of the Brg1 intranuclear stain can exclude the possibility of neuroendocrine carcinoma, NUT carcinoma, rhabdomyosarcoma, poorly differentiated synovial sarcoma, and the SMARCA4 deficient thoracic tumor, respectively.