1. The second segment of left lobe liver cancer is adjacent to stomach or small intestine (duodenum, jejunum, ileum), the third segment of left lobe liver cancer is adjacent to spleen area of colon, and the fifth segment of right lobe liver cancer is adjacent to liver area of colon or ascending colon (and interposition colon formed after cirrhosis or surgery). The stomach is the least likely to be damaged because the stomach wall is thicker, the stomach is more mobile, and it is possible to drink water before surgery (bile in the gallbladder is also less likely to be damaged). The small intestine is also less likely to be injured because it is not fixed by ligaments and has excellent mobility. The colon is the most easily damaged because it is fixed by ligaments and has a thin wall. Injury can be prevented by artificial ascites or air injection. 2, ablation therapy to avoid damage to the gallbladder. (1) train the patient to breathe steadily, which is related to whether the position of the gallbladder is in the same body position when entering the needle; (2) the position of the needle tip of the guide needle, the CT scan should include seeing the needle tip after the foot side or head side also in the scan at least 2 layers to confirm that all are normal tissues; (3) the main needle must enter the needle in steps; (4) if the gallbladder is pierced, the bile in the gallbladder can be sucked out to avoid biliary peritonitis. (3) Ablation of hepatocellular carcinoma at the top of the diaphragm. Pneumothorax occurs mainly because of stabbing the pleura, but sometimes patients have pleural diseases, such as pleural adhesions. Ablation treatment may induce pneumothorax, or the occurrence of pneumothorax is just coincidental. In any case, before and after performing ablation therapy, pay attention to auscultation and leave a lung window for clarification, especially for hepatocellular carcinoma near the diaphragm in the seventh and eighth segment of the right lobe of the liver. In addition, we have seen some cases of pneumothorax 24 hours after surgery. Therefore, if the symptom of breath-holding occurs after surgery, we should think of pneumothorax and promptly investigate and do chest X-ray for clarification. 4. Ablation of tumors near the para-aorta. (1) preoperative explanation may require open chest; (2) it will cause hoarseness because it will damage the left recurrent laryngeal nerve; (3) the pulmonary artery is located on its dorsal side, which is also easy to be damaged. 5. Do not damage the portal vein and inferior vena cava outside the liver during ablation. Pay attention to the intrahepatic needle transfer. Ablation with water can increase the ablation range.