AIM: To prospectively assess the changes in parameters of computed tomography (CT) perfusion pre-and post-transarterial chemoembolization (TACE) of hepatocellular carcinoma (HCC) in different treatment response groups, and to correlate the changes with various responses of HCC to TACE. METHODS: Thirty-nine HCC patients underwent CT perfusion examinations pre-(1 d before TACE) and post-treatment (4 wk after TACE). The response evaluation criteria for solid tumors (RECIST) were referred to when treatment responses were distributed. Wilcoxon-signed ranks test was used to compare the differences in CT perfusion parameters pre-and post-TACE for different response groups. RESULTS: Only one case had treatment response to CR and the CT perfusion maps of post-treatment lesion displayed complete absence of signals. In the PR treatment response group, hepatic artery perfusion (HAP), hepatic arterial fracture (HAF) and hepatic blood volume (HBV) of viable tumors post-TACE were reduced compared with pre-TACE (P = 0.001, 0.030 and 0.001, respectively). In the SD group, all CT perfusion parameters were not significantly different pre-and post-TACE. In the PD group, HAP, HAF, portal vein perfusion (PVP) and hepatic blood flow (HBF) of viable tumors post-TACE were significantly increased compared with pre-TACE (P = 0.005, 0.012, 0.035 and 0.005, respectively). CONCLUSION: Changes in CT perfusion parameters of viable tumors are correlated with different responses of HCC to TACE. Therefore, CT perfusion imaging is a feasible technique for monitoring response of HCC to TACE. AIM: To prospectively assess the changes in parameters of computed tomography (CT) perfusion pre-and post-transarterial chemoembolization (TACE) of hepatocellular carcinoma (HCC) in different treatment response groups, and to correlate the changes with various responses of HCC to TACE METHODS: Thirty-nine HCC patients underwent CT perfusion examinations pre- (1 d before TACE) and post-treatment (4 wk after TACE). The response evaluation criteria for solid tumors (RECIST) were referred to when treatment responses were distributed. Wilcoxon-signed ranks test was used to compare the differences in CT perfusion parameters pre-and post-TACE for different response groups. RESULTS: Only one case had treatment response to CR and the CT perfusion maps of post-treatment lesion displayed complete absence of signals. In the PR treatment response group, hepatic artery perfusion (HAP), hepatic arterial fracture (HAF) and hepatic blood volume (HBV) of viable tumors post-TACE were reduced compared wit In the SD group, all CT perfusion parameters were not significantly different pre-and post-TACE. In the PD group, HAP, HAF, portal vein perfusion (PVP ) and hepatic blood flow (HBF) of viable tumors post-TACE were significantly increased compared to pre-TACE (P = 0.005, 0.012, 0.035 and 0.005, respectively). CONCLUSION: Changes in CT perfusion parameters of viable tumors are correlated with different responses of HCC to TACE. Thus, CT perfusion imaging is a feasible technique for monitoring response of HCC to TACE.