BCOR and clear cell sarcoma of kidney: BCOR-ITD is a common genetic alteration detected in clear cell sarcoma of the kidney (CCSK), primitive myxoid mesenchymal tumor of infancy (PMMTI) and in some central nervous system (CNS) high-grade neuroepithelial tumor (HGNET) first reported as CNS HGNET-BCOR (9–14).