Preoperative evaluation with T-staging system for hilar cholangiocarcinoma

Table 1 Revised preoperative T staging system for patients with hilar cholangiocarcinoma

T Stage	Description
T1	Tumor involving biliary confluence ± unilateral extension to 2° biliary radicles
	No liver atrophy or portal vein involvement
T2	Tumor involving biliary confluence ± unilateral extension to 2° biliary radicles with ipsilateral portal vein involvement ± ipsilateral hepatic lobar atrophy
	No main portal vein involvement
T3	Tumor involving biliary confluence + bilateral extension to 2° biliary radicles; OR unilateral extension to 2° biliary radicles with controlateral portal vein involvement; OR unilateral extension to 2° biliary radicles with controlateral hepatic lobar atrophy; ralateral hepatic lobar atrophy; phy; OR main or bilateral portal venous involvement