Ar-He knife can treat tumors. Ar-He knife is a kind of cryoablation, which is guided by CT or MRI, and the ablation needle is inserted into the tumor, and after connecting argon and helium, the tumor cells are killed by repeated cooling and heating. If the tumor is limited and small, it is even possible to kill the tumor completely and achieve a cure through Ar-He knife treatment. However, if the tumor is large, it is difficult to kill the tumor completely, but the patient’s tumor load can be reduced through Ar-He knife treatment. Compared with thermal ablation such as microwave and radiofrequency, argon helium knife causes less pain to the patient and the scope of treatment is clearer, but the disadvantage is that the procedure takes relatively longer time.