SMARCB1 and rhabdoid tumor: Unlike primary rhabdoid tumors, such as malignant rhabdoid tumors, atypical teratoid/rhabdoid tumors, SMARCA4-deficient thoracic sarcomas, and epithelioid sarcoma, which often show alterations in SMARCB1 (INI1) or SMARCA4, cutaneous RSCC does not exhibit such inactivation [6,7].