Prognostic factors of pancreatic neck cancer.

Abstract

355 Background: Pancreatic neck cancer is surrounded by common hepatic artery (CHA), gastroduodenal artery (GDA) and portal vein (PV), and easily invades nerve plexus around main arteries, such as CHA, celiac trunk, and superior mesenteric artery (SMA). Therefore, the resectablity of pancreatic neck cancer is low, and the biological behaviors have been unclear. In this study, we reviewed 59 resected pancreatic neck cancer cases to identify the prognostic factors. Methods: From 2000 to 2012, 305 patients with pancreatic cancer underwent surgical resection, and in 59 patients (19%) among them with pancreatic neck cancer, 49 patients underwent pancreatoduodenectomy, 5 subtotal pancreatectomy, 4 distal pancreatectomy with en-bloc celiac axis, and 1 total pancreatectomy. We defined borderline resectable pancreatic cancer as tumor abutted CHA, celiac trunk, or SMA, and classified radiographic types of PV invasion into A (normal), B (unilateral), C (bilateral), or D (complete obstruction) by CT imaging. We analyzed retrospectively clinicopathological characteristics and prognostic factors for pancreatic neck cancer. Results: Pancreatic neck cancer was smaller than other located pancreatic cancer (21.1±7.0 vs. 32.0±13.5 mm, P<0.01), and the rate of pathological PV invasion was higher in pancreatic neck cancer (36 vs. 20%, P=0.01). In patients with pancreatic neck cancer, pathological PV invasion was observed in 0% of type A (0/9), 14% of type B (3/22), 48% of type C (10/21), and 86% of type D (6/7), and 37 patients (63%) had lymph node metastasis. In 32 patients with borderline resectable pancreatic neck cancer, neoadjuvant chemo(radiation)therapy (NAC) reduced the R1 rates (P=0.04) Pathological PV invasion, tub2/3 and lymph node ratio >0.1 were independent poor prognostic factors for pancreatic neck cancer (P<0.01, P=0.03, and P=0.03, odds ratio; 7.1, 2.8, and 3.1, respectively). Conclusions: Pancreatic neck cancer often had PV invasion even if CT imaging showed unilateral abutment, indicating that combined PV resection may be necessary for R0 resection of pancreatic neck cancer with radiological PV abutment. NAC may improve R0 resection rates and postoperative survival for pancreatic neck cancer.