AIM To evaluate the relationship between the location of hepatocellular carcinoma(HCC) and the efficacy of transarterial chemoembolization(TACE).METHODS We evaluated 115 patients(127 nodules), excluding recurrent nodules, treated with TACE between January 2011 and June 2014. TACE efficacy was evaluated according to m RECIST. The HCC location coefficient was calculated as the distance from the central portal portion to the HCC center(mm)/liver diameter(mm) on multiplanar reconstruction images rendered(MPR) to visualize bifurcation of the right and left branches of the portal vein and HCC center. The HCC location coefficient was compared between complete response(CR) and non-CR groups in Child-Pugh grade A and B patients.RESULTS The median location coefficient of HCC among all nodules, the right lobe, and the medial segment was significantly higher in the CR group than in the non-CR group in the Child-Pugh grade A patients(0.82 vs 0.62, P < 0.001; 0.71 vs 0.59, P < 0.01; 0.81 vs 0.49, P < 0.05, respectively). However, there was no significant difference in the median location coefficient of the HCC in the lateral segment between in the CR and in the non-CR groups(0.67 vs 0.65, P > 0.05). On the other hand, in the Child-Pugh grade B patients, the HCC median location coefficient in each lobe and segment was not significantly different between in the CR and in the non-CR groups.CONCLUSION Improved TACE efficacy may be obtained for HCC in the peripheral zone of the right lobe and the medial segment in Child-Pugh grade A patients. AIM To evaluate the relationship between the location of hepatocellular carcinoma (HCC) and the efficacy of transarterial chemoembolization (TACE). METHODS We evaluated 115 patients (127 nodules), excluding recurrent nodules, treated with TACE between January 2011 and June 2014. TACE efficacy was evaluated according to m RECIST. The HCC location coefficient was calculated as the distance from the central portal portion to the HCC center (mm) / liver diameter (mm) on multiplanar reconstruction images rendered (MPR) to visualize bifurcation of the right and left branches of the portal vein and HCC center. The HCC location coefficient was comparison between complete response (CR) and non-CR groups in Child-Pugh grade A and B patients. RESULTS The median location coefficient of HCC among all nodules, the right lobe , and the medial segment was significantly higher in the CR group than in the non-CR group in the Child-Pugh grade A patients (0.82 vs 0.62, P <0.001; 0.71 vs 0.59, P <0.01; 0.81 vs 0.49, P <0.05, respectively). However, there was no significant difference in the median location coefficient of the HCC in the lateral segment between in the CR and in the non-CR groups (0.67 vs 0.65, P> 0.05). On the other hand , in the Child-Pugh grade B patients, the HCC median location coefficient in each lobe and segment was not significantly different between in the CR and in the non-CR groups. CONCLUSION Improved TACE efficacy may be obtained for HCC in the peripheral zone of the right lobe and the medial segment in Child-Pugh grade A patients.