Optimal Region of Lymph Node Dissection in Distal Pancreatectomy for Left-Sided Pancreatic Cancer Based on Tumor Location

Background The optimal lymph node (LN) dissection for left-sided pancreatic cancer based on tumor location has remained unknown. In particular, the efficacy of LN dissection around the common hepatic artery and the celiac axis for distal tumors has not been established. This study was designed to elucidate the frequency and prognostic impact of LN metastasis, focusing on tumor location. Methods Data from 110 patients with invasive pancreatic cancer who underwent distal pancreatectomy between 2007 and 2020 were collected. We used a quantitative value?the distance between the left side of the portal vein and the right side of tumor (DPT)?to define the tumor location. LN stations were divided into two groups: peripancreatic lymph nodes (PLN) and non-PLN. We then analyzed the frequency of LN metastasis based on the tumor location and prognostic factors. Results Non-PLN metastasis was observed in 7.3% of patients. Non-PLN metastasis was found only in patients with a DPT < 20 mm. Patients with non-PLN metastasis exhibited a significantly worse prognosis than those with only-PLN metastasis (median survival time: 20.3 vs. 42.5 months, p = 0.048). Multivariate analysis for survival indicated that tumor size > 4 cm (hazard ratio [HR]: 2.23, p = 0.012) and metastasis in the non-PLN region (HR: 3.02, p = 0.015), and inability to undergo adjuvant chemotherapy (HR: 2.81, p = 0.0018) were also associated with poor prognosis. Conclusions Dissection of the non-PLN region can be avoided in selected patients with DPT >= 20 mm.

Automated summary

This study explored the importance of lymph node dissection for left-sided pancreatic cancer based on tumor location, showing that dissection of the non-PLN region can be avoided in patients with DPT >= 20 mm. Non-PLN metastasis was associated with a poorer prognosis compared to only-PLN metastasis.