MKI67 and neoplasm: Ikeda et al. proposed a treatment selection map for metastatic pancreatic NEN based on the Ki-67 index and liver involvement as follows [47]: SSA treatment for patients with a relatively small tumor burden and low Ki-67 index [31], cytotoxic agents for patients with a relatively large tumor burden and high Ki-67 index [48, 49], and MTAs for patients with intermediate tumor volume and/or Ki-67 index [32, 34].