Subsequently the loss of nuclear SMARCB1 expression has been identified in renal medullary carcinoma, epithelioid sarcoma, a subset of collecting duct carcinoma and epithelioid malignant peripheral nerve sheath tumor (MPNST) and rare rhabdoid variants of carcinoma from digestive system and sinonasal tract [2–4, 12–14]. The gene discussed is SMARCB1; the disease is malignant peripheral nerve sheath tumor.