Objective To objectively evaluate the endpoint ot transcatheter arterial chemoembolization (TACE) using two dimensional color-coded digital subtraction angiography (2D-ccDSA).Methods Retrospective analysis of twenty-four patients diagnosed with hepatocellular carcinoma (HCC),treated by TACE and evaluated by post-processed 2D-ccDSA.All patients were examined by DSA before and after TACE procedure,all these DSA series were converted into color-code images,the time density curve (TDC) was derived from the 2D-ccDSA imaging.Time-to-peak (TTP) was measured for the ostia of the catheter,the origin of the tumor feeding artery (TFA) and the embolized site of the TFA; maximal TDC enhancement was measured for selected spots of the tumor parenchyma.The tumor blood supply time (TBST) for pre and post-TACE was calculated accordingly.Data were interpreted with paired t test using SPSS.Results The TTP of the ostia of the catheter and the origin of the tumor feeding artery (TFA) before TACE were (3.47 ± 0.96) and (4.09 ± 1.09) s,after the TACE were (3.49 ± 1.02) and (3.78 ± 1.05) s,respectively.There was no statistical difference between the pre-and post-procedural TTP of the two landmarks (t values were 0.10 and 1.15,P values were 0.92 and 0.26).TTP at the embolized site of the main TFA were [(4.62± 1.16) and (5.59± 1.57)s]for pre and post-TACE,the tumor blood supply time (TBST) was greatly delayed compared with that after the TACE procedure [(1.82± 1.10)s and (0.52±0.41)s].The mean maximal TDC enhancements of the tumor parenchyma areas were (3.03±0.88)units before TACE and (1.10±0.67)units after TACE.The differences were all statistically significant (t values were 3.32,6.04 and 8.93,respectively,P<0.01) Conclusion It is feasible to use 2D-ccDSA to objectively assess the endpoint of TACE procedures. Key words: Liver neoplasms ; Angiography,digital subtraction; Radiology,interventional