Abstract: Objective: To collect the clinical materials of primary liver cancer patients treated by gamma knife and analyze the treatment methods as well as short-term efficacy,and to provide a reference for the clinical treatment of primary liver cancer patients. Methods: A total of 633 patients with inoperable primary liver cancer were treated by body gamma knife.According to the TNM staging method of Union for International Cancer Control(UICC), there were 351 cases with clear TNM staging.Among them, there were 251 cases (71.5%) at T3 stage and 57 cases(16.2%) at T4 stage.The prescription dose of 200-600 cGy each time to the 40%-85% dose line covering the planned target volume(PTV), this program was performed 5 times per week, and the number of treatment ranged from 2 to 13.The biochemical and imaging changes were observed 2-3 months after treatment to evaluate the short-term efficacy. Results: During the treatment, 229(36.2%)patients had adverse reactions,100 (15.8%) patients appeared the reduced white blood cells, and 137 (21.6%) patients appeared the reduced platelets.On discharge from the hospital, 601 patients were improved, 22 patients had no obvious change, 5 cases were worse, and 5 cases died.The proportion of improved patients who received the cumulative dose between 3 000 cGy to 4 000 cGy was higher than those who received the cumulative dose less than 3 000 cGy(P<0.05).After treatment, the curative effects were evaluated in 45 patients during two and three months, including PR 77.8%(35/45) and SD 22.2%(10/45), and the total effective rate was 77.8%(35/45).No statistical differences in effective rates were found between different tumor diameter, single dose, and cumulative dose groups(P>0.05). Conclusion: The proportion of adverse reactions in the primary liver cancer patients treated with body gamma knife is relatively low and the short-term efficacy is ideal.Body gamma knife treatment is a safe and effective treatment method for the primary liver cancer patients.

Key words: gamma knife, short-term efficacy, liver neoplasms, clinical report