Abstract: Objective To evaluate the efficacy of three-dimensional conformal radiotherapy（3DCRT）to treat primary liver cancer （PLC）and investigate the prognostic factors associated with its use. Methods PLC patients（n = 283）were treated with 3DCRT using a total dose of 51.85±6.55 Gy（4.55±1.02 Gy/fraction，3 fractions/week，10±4 total fractions）. Results The response rate（CR+PR）was 47.35%（134/283）.The 1-，3-，and 5-year overall survival rates were 57.0%，29.0% and 18.0%，respectively.Gender，CLIP stage，GTV，PVTT and Child-Pugh class were found to significantly affect overall survival（P<0.01）.Independent prognostic factors were gender（P=0.008），GTV（P=0.007），PVTT（P=0.006）and Child-Pugh class（P=0.003）.Conclusion Gender，GTV，PVTT and Child-Pugh class may be independent prognostic factors when using 3DCRT to treat PLC.

Key words: Liver neoplasms, Three-dimensional conformal radiotherapy, Prognosis