Table 1. Demographics, operation details, clinicopathologic features.

Values are presented as mean ± standard deviation, number (%), or median (range).

rR0, microscopic safety margin >1 mm; rR1, 0 mm < microscopic safety margin ≤ 1 mm; cR1, safety margin = 0 mm; ASA PS, American Society of Anesthesiologists physical status; PPPD, pylorus preservingpancreaticoduodenctomy; PRPD, pylorus resecting pancreaticoduodenectomy; PV-SMV, portal vein-superior mesenteric vein.

^a)Proportion of number of patients receiving PPPD to all patients receiving curative resection. ^b)Major vascular invasion means cancer invade to superior mesentery artery or portal vein or superior mesentery vein in final pathological findings.