The standard treatment for locally advanced unresectable (UR-LA) pancreatic ductal adenocarcinoma (PDAC) is chemo-radiotherapy. Surgery following chemo-radiotherapy (conversion surgery), has been considered a useful strategy and has been used for UR-LA PDAC. The current study presents the case of a 43-year-old woman who complained of back pain. A radiological examination revealed a pancreatic tumor in contact with >270 degrees of the superior mesenteric artery (SMA) perimeter, with invasion extending from the superior mesenteric vein (SMV) to the portal vein (PV). An endoscopic ultrasonography-guided fine needle aspiration biopsy revealed adenocarcinoma as the pathological diagnosis and the patient was diagnosed with UR-LA PDAC. Following 12 courses of combined gemcitabine plus nab-paclitaxel (GnP) for 9 months, the extent of tumor invasion to the SMA and SMV was improved and the level of cancer antigen (CA) 19-9 decreased. A pancreatoduodenectomy with PV resection and reconstruction using a left renal vein graft were performed. Pathological examination revealed that the operative outcome was R0 (no residual tumor) resection and the patient was alive 19 months after the initial treatment (9 months post surgery), however, there was local tumor recurrence. Between March 2015 and February 2016 a total of 10 cases of UR-LA PDAC were encountered at the Department of General Surgery, Chiba University Hospital (Chiba, Japan), in which GnP therapy was performed. Including the present case, 6 of the 11 cases (55%) underwent conversion surgery with curative resection. Kaplan-Meier analysis revealed that patients treated with conversion surgery presented significantly longer overall survival (OS) than those treated with no conversion surgery (median OS, 22.5 vs. 11 months; P=0.047, Wilcoxon test). The minimum reduction of CA19-9 was 67%. In conclusion, conversion surgery following GnP therapy is a desirable option for UR-LA PDAC. A significant reduction in the CA19-9 levels may be useful in determining the timing of changeover from medicine to surgery in patients with UR-LA PDAC in whom conversion surgery is being considered.
Keywords: cancer antigen 19-9; conversion surgery; gemcitabine plus nab-paclitaxel; locally advanced unresectable pancreatic cancer.