AIM: To expand the living donor liver transplantation(LT) pool of eligible patients with hepatocellular carcinoma(HCC) using new morphological and biological criteria.METHODS: Patients with HCC who underwent living donor LT(LDLT) from March 2005 to May 2013 at the National Cancer Center Korea(NCCK) were enrolled. We performed the 18F-fluorodeoxyglucose positron emission tomography/computed tomography(PET/CT)before LDLT. Overall and disease-free survival analysis was done in patients to evaluate the usefulness of new NCCK criteria using PET/CT and total tumor size(10 cm).RESULTS: We enrolled a total of 280 patients who pathologically confirmed to have HCC and performed the PET/CT before transplantation. Among them, 164(58.6%) patients fulfilled the NCCK criteria and 132 patients(47.1%) met the Milan criteria. Five-year overall and disease-free survival rates for patients who fulfilled the NCCK criteria showed 85.2% and 84.0%, respectively, and were significantly higher than those beyond the NCCK criteria(60.2% and 44.4%, respectively; P < 0.001). The correlation analysis between preoperative imaging tests and pathologic reports using Cohen’s Kappa demonstrated the better results in the NCCK criteria than those in the Milan criteria(0.850 vs 0.583). The comparison of diseasefree analysis among the NCCK, Milan, and University of California, San Francisco(UCSF) criteria using the receiver operating characteristics curves revealed the similar area under the curve value criteria(NCCK vs Milan, P = 0.484; NCCK vs UCSF, P = 0.189 at 5-years).CONCLUSION: The NCCK criteria using hybrid concept of both morphological and biological parameters showed an excellent agreement between preoperative imaging and pathological results, and favorable survival outcomes. These new criteria might select the optimal patients with HCC waiting LDLT and expand the selection pool. AIM: To expand the living donor liver transplantation (LT) pool of eligible patients with hepatocellular carcinoma (HCC) using new morphological and biological criteria. METHODS: Patients with HCC who underwent living donor LT (LDLT) from March 2005 to May 2013 at the National Cancer Center Korea (NCCK) were enrolled. We performed the 18F-fluorodeoxyglucose positron emission tomography / computed tomography (PET / CT) before LDLT. Overall and disease-free survival analysis was done in patients to evaluate the usefulness of new NCCK criteria using PET / CT and total tumor size (10 cm) .RESULTS: We enrolled a total of 280 patients who pathologically confirmed to have had HCC and performed the PET / CT before transplantation. Among them, 164 (58.6%) patients fulfilled the NCCK criteria and Five-year overall and disease-free survival rates for patients who fulfilled the NCCK criteria showed 85.2% and 84.0%, respectively, and were significantly higher than those beyond the correlation analysis between preoperative imaging tests and pathologic reports using Cohen’s Kappa demonstrated the better results in the NCCK criteria than those in the Milan criteria (0.850 vs 0.583). The comparison of diseasefree analysis among the NCCK, Milan, and University of California, San Francisco (UCSF) criteria using the receiver operating characteristics of the similar area under the curve value criteria (NCCK vs Milan, P = 0.484; NCCK vs UCSF, P = 0.189 at 5-years) .CONCLUSION: The NCCK criteria using hybrid concept of both morphological and biological parameters showed an excellent agreement between preoperative imaging and pathological results, and favorable survival outcomes. These new criteria might select the optimal patients with HCC waiting LDLT and expand the selection pool.