Histologic tumor involvement of superior mesenteric vein/portal vein predicts poor prognosis in patients with stage II pancreatic adenocarcinoma treated with neoadjuvant chemoradiation

BACKGROUND: Studies have shown that superior mesenteric vein (SMV)/portal vein (PV) resection with pancreaticoduodenectomy (PD) is safe and feasible for patient with pancreatic adenocarcinoma (PAC). However, the prognostic significance of tumor involvement of the resected vein in patients who received neoadjuvant therapy is unclear. METHODS: The authors evaluated 225 consecutive patients with stage II PAC who received neoadjuvant therapy and PD with or without SMV/PV resection. The resected SMV/PV was entirely submitted for histologic assessment and reviewed in all cases. Tumor involvement of the SMV/PV was correlated with clinicopathologic features and survival. RESULTS: Among the 225 patients, SMV/PV resection was performed in 85 patients. Histologic tumor involvement of the resected SMV/PV was identified in 57 patients. Histologic tumor involvement of the SMV/PV was associated with larger tumor size, higher rates of positive margin, and local/distant recurrence. By multivariate analysis, tumor involvement of the SMV/PV was an independent predictor of both disease-free survival (DFS) and overall survival (OS). However, addition of venous resection to PD itself had no impact on either DFS or OS compared with those with PD alone. CONCLUSIONS: Histologic tumor involvement of the SMV/PV is an independent predictor of both DFS and OS in patients with stage II PAC treated with neoadjuvant therapy and PD. Complete histologic evaluation of the resected SMV/PV is important for the prognosis in patients with PAC who received neoadjuvant therapy and PD.