Patterns of venous collateral development after splenic vein occlusion associated with surgical and oncological outcomes after distal pancreatectomy

Aims

Splenic vein occlusion (SpVO) due to a pancreatic tumor may result in the development of collateral circulation and left-sided portal hypertension. This study aimed to investigate the impact of SpVO on distal pancreatectomy (DP) and provide insights about the management of such cases.

Methods

This retrospective analysis included 124 patients who underwent DP from 2014 to 2022. A subgroup analysis was performed on 88 patients who underwent DP for pancreatic ductal adenocarcinoma (PDAC).

Results

SpVO was found in 26 (20.8%) patients. The patients with SpVO had significantly larger splenic volumes and lower platelet counts. Compared to the patients with patent splenic veins (SpVs), the patients with SpVO underwent significantly longer operations (p = 0.006), with a higher incidence of postoperative complications (p = 0.002). We classified the collateral routes associated with SpVO into five patterns. The most common pattern was the left gastroepiploic vein type, which was associated with a tumor of the pancreatic body. In patients with PDAC, SpVO was associated with larger tumors, microscopic vascular permeation, and peritoneal recurrence. However, the differences between overall and recurrence-free survival rates in the patients with SpVO vs those with patent SpVs were not significant.

Conclusions

SpVO causes left-sided portal hypertension, which can be a risk for perioperative complications in DP. Operative planning based on the classification of collateral flow patterns may help prevent intraoperative congestion and perioperative complications.