Some expert centers have suggested the use of strict inclusion criteria to considerer liver transplantation in metastatic NETs such as (i) well-differentiated NETs (Ki-67 < 5%); (ii) portosystemic tumor drainage; (iii) young patients < 55 years; (iv) stable disease for at least 6 months; (v) pre-transplant R0 primary tumor resection; (vi) hepatic tumor involvement < 50% of the liver volume; and (vii) absence of extra-hepatic disease [143]. Here, MKI67 is linked to neoplasm.