NPM1 and neoplasm: For 70–80% of these neoplasms, the binding partner of ALK is nucleophosmin (NPM1); in the remaining subset, ALK has been found to fuse with various partners, thereby creating many different fusion ALK proteins, including RNF213-ALK (or ALO17-ALK), TFG-ALK, MSN-ALK, TPM3-ALK, TPM4-ALK ATIC-ALK, MYH9-ALK, and CLTC-ALK [2].