Patients
A total of 692 patients with PDAC who underwent curative resection in the Department of Pancreatic Cancer, Tianjin Medical University Cancer Institute and Hospital between January 2011 and December 2018 were eligible for this study. Eligibility criteria included: (I) patients with PDAC; (II) patients with R0 resection; (III) patients who were completely followed up. Exclusion criteria included: (I) patients with history of pancreatectomy or other malignancy; (II) patients with arterial tumor contact (celiac axis, superior mesenteric artery, or common hepatic artery); (III) patients with distant metastasis; (V) patients who accepted neoadjuvant chemotherapy; (VI) patients who died during the initial hospital stay or 1 month after surgery. After excluding 10 patients with pancreatic mucinous carcinoma, 9 patients with pancreatic adenosquamous carcinoma, 1 patient with lung cancer, 1 patient with gastric cancer, 3 patients with breast cancer, 10 patients with R1 resection, 1 patient with R2 resection, 14 patients confirmed with distant metastasis during laparotomy, 22 patients lost, 4 patients accepted neoadjuvant chemotherapy, 2 patients died during the initial hospital stay and 3 patients died within 1 month after surgery, ultimately, 612 patients were included in this study.