Comparison of the long-term outcomes of uncinate process cancer and non-uncinate process pancreas head cancer: poor prognosis accompanied by early locoregional recurrence

Abstract

The embryologic and anatomic peculiarity of the uncinate process may result in distinct clinical features, but few studies have addressed the uncinate process cancer. The purpose of this study was to compare the clinicopathologic characteristics and identify the prognostic factors that affect the survival and recurrence of pancreatic head cancer by tumor location. Between January 2002 and December 2008, 453 patients (161 with uncinate and 292 with non-uncinate process cancer) were treated for pancreatic head cancer. Clinicopathologic variables were analyzed by tumor location. Invasion into the superior mesenteric artery (SMA) occurred more frequently (p < 0.001), and overall resectability (p = 0.003), curative resection (p < 0.001), and R0 resection rates (22.3% vs 35.6%; p = 0.003) were lower for uncinate process cancer. Furthermore, overall survival after R0 resection was lower for uncinate process cancer (median 21 vs 26 months; p = 0.018), and this was accompanied by more frequent (p = 0.038) and earlier (median 13 vs 52 months; p < 0.001) locoregional recurrence. Concurrent chemoradiation increased overall (median, 26 vs 13 months; p < 0.001) and disease-free survival (median, 15 vs 6 months; p < 0.001) of uncinate and non-uncinate process cancer, respectively, after curative-intended resection. In uncinate process cancer, frequent invasion into the SMA led to lower resectability. Furthermore, lower survival after R0 resection was accompanied with frequent and early locoregional recurrence. Strategies to improve surgical and perioperative locoregional control are required for uncinate process cancer.