Prognostic Impact of the Preoperative Systemic Inflammation Score in Patients With Pancreatic Ductal Adenocarcinoma

Backgroud: The systemic inflammation score (SIS), which is based on the preoperative lymphocyte-to-monocyte ratio (LMR) and serum albumin (Alb) level, is a prognostic indicator for several cancer types. However, the prognostic significance of the SIS in pancreatic ductal adenocarcinoma (PDAC) remains unknown. Methods: Seventy-eight patients who underwent radical surgery for PDAC were categorized as follows: SIS 0 (LMR ≥3.51 and Alb ≥4.0 g/dl), n = 26; SIS 1 (LMR <3.51 or Alb <4.0 g/dl), n = 29 and SIS 2 (LMR <3.51 and Alb <4.0 g/dl), n=23. Results: The tumour size sequentially increased in SIS 0, 1 and 2 groups. A higher SIS was associated with increased vascular invasion, perineural invasion and surgical margin positivity rate. Recurrence-free survival (RFS) rates between the SIS 1 and 2 groups showed no significant difference However, patients of the SIS 1 and 2 groups had poorer outcomes than those of the SIS 0 group for RFS. Overall survival (OS) rates between the SIS 1 and 2 groups also showed no significant difference. However, patients of the SIS 1 and 2 groups had poorer outcomes than those of the SIS 0 group for OS. The SIS was an independent prognostic factor for RFS and OS. Discussion: The SIS is a simplified prognostic factor for patients with PDAC.