Occult gallbladder cancer refers to those who have undergone conventional cholecystectomy without detecting gallbladder cancer preoperatively and intraoperatively, and whose diagnosis of gallbladder cancer is confirmed by postoperative pathology. The postoperative pathology results can only be obtained one week after surgery, so the problem is whether to perform radical surgery again. If the postoperative pathological section reveals that the cancer only invades to the mucosal layer or muscular layer, and the location is far from the liver and gallbladder duct, the purpose of radical surgery can be achieved by simple cholecystectomy, and the second radical surgery is not necessary. The lymphatic metastasis of gallbladder cancer first involves the gallbladder triangle and the lymph nodes distributed along the common bile duct. The cancer located in the gallbladder neck, especially in the gallbladder duct, has earlier lymph node metastasis due to its location near the gallbladder triangle. The postoperative recurrence rate of gallbladder neck carcinoma was also significantly higher than that of carcinoma at the base of the gallbladder body. Therefore, for occult gallbladder cancer located in the gallbladder neck and gallbladder duct, regardless of which layer of the gallbladder wall it invades, lymph node dissection around the hepatoduodenal ligament should be performed again. For cryptogenic gallbladder cancer with infiltration deeper than the muscular layer, positive cut margins and positive gallbladder triangle lymph node biopsy, a second radical surgery should be performed. Principles of radical surgery: 1. If the postoperative pathological section reveals that the cancer only invades into the mucosal layer or muscle layer, complete cholecystectomy alone can achieve the purpose of radical treatment, so the second radical surgery is not necessary. The lymphatic metastasis of gallbladder cancer firstly involves the gallbladder triangle and the lymph nodes distributed along the common bile duct. 2.Cancer located in the gallbladder neck, especially in the gallbladder duct, occurs earlier due to its location near the gallbladder triangle. The postoperative recurrence rate of gallbladder neck cancer is also significantly higher than that of cancer at the base of the gallbladder body. Therefore, for occult gallbladder cancer located in the gallbladder neck and gallbladder duct, regardless of which layer of the gallbladder wall it invades, lymph node dissection around the hepatoduodenal ligament should be performed again. 3.For occult gallbladder cancer with infiltration depth exceeding the muscular layer, positive cut margin and positive gallbladder triangle lymph node biopsy, a second radical surgery should also be performed.