Current status and progress in laparoscopic surgery for gallbladder carcinoma

Table 1 Summary of gallbladder carcinoma T staging according to the American Joint Committee on Cancer 8^th edition and the corresponding surgical approach

	AJCC 8th T staging classification	Surgical approach
Tis	Carcinoma in situ	Simple cholecystectomy
T1a	Tumor invades the lamina propria	Simple cholecystectomy
T1b	Tumor invades the muscular layer	Extended cholecystectomy including cholecystectomy + lymphadenectomy ± hepatectomy (current consensus)/simple cholecystectomy (under debate)
T2a	Tumor invades the perimuscular connective tissue on the peritoneal side, without involvement of the serosa	Extended cholecystectomy including cholecystectomy + lymphadenectomy ± hepatectomy ± bile duct resection and reconstruction
T2b	Tumor invades the perimuscular connective tissue on the hepatic side, with no extension into the liver	Extended cholecystectomy including cholecystectomy + lymphadenectomy + hepatectomy ± bile duct resection and reconstruction
T3	Tumor perforates the serosa (visceral peritoneum) and/or directly invades the liver and/or one other adjacent organ or structure, such as the stomach, duodenum, colon, pancreas, omentum or extrahepatic bile ducts	Extended cholecystectomy including cholecystectomy + lymphadenectomy + hepatectomy ± bile duct resection and reconstruction (some T3 without distant metastasis)/hepatopancreatoduodenectomy (under debate)
T4	Tumor invades the main portal vein or hepatic artery or invades two or more extrahepatic organs or structures	No significant benefit from surgery

AJCC: American Joint Committee on Cancer.