[Long-Term Survival after Locally Advanced Pancreatic Ductal Adenocarcinoma Treated with Multidisciplinary Therapy - A Case Report].

A 60-year-old man visited a hospital with concerns about his physical health, including weight loss, thirst, and polyuria. He was diagnosed with acute onset of diabetes, and a pancreatic head tumor was observed on imaging studies. Computed tomography(CT)indicated that the tumor infiltrated the surrounding major vessels, portal vein(PV, 360 degrees), and superior mesenteric artery(SMA, <180 degrees). Endoscopic ultrasound-guided fine needle aspiration(EUS-FNA)was performed, and he was diagnosed with a borderline resectable(BR)clinical Stage IV a pancreatic ductal adenocarcinoma (PDAC). Chemoradiation therapy(CRT, S-1 plus gemcitabine [GEM] concurrent with 50.4 Gy radiation)followed by chemotherapy( GEM)was performed until a tumor response indicating sufficient reduction of SMA infiltration was observed on imaging studies. Twelve months after initiation of treatment, a pancreaticoduodenectomy and PV resection/reconstruction were performed. The pathological stage was ypT3N0M0(ypStage III ), and SMA infiltration was not detected in the resected specimen. He was discharged after an uneventful course following surgery, and adjuvant S-1 chemotherapy was continued from post-operative day 67 for 4 months. Now at post-operative 57 month, he has survived without recurrence. There have been some reports detailing long-term survival of patients with BR tumors who underwent multidisciplinary therapy as curative resection following preoperative CRT and postoperative adjuvant chemotherapy. During preoperative treatment, it is important to monitor the effects and determine the suitable timing to perform surgery to achieve long-term survival.