This statement was developed to promote international consensus on the definition of borderline resectable pancreatic ductal adenocarcinoma (BR-PDAC) which was adopted by the National Comprehensive Cancer Network (NCCN) in 2006, but which has changed yearly and become more complicated. Based on a symposium held during the 20th meeting of the International Association of Pancreatology (IAP) in Sendai, Japan, in 2016, the presenters sought consensus on issues related to BR-PDAC. We defined patients with BR-PDAC according to the three distinct dimensions: anatomical (A), biological (B), and conditional (C). Anatomic factors include tumor contact with the superior mesenteric artery and/or celiac artery of less than 180° without showing stenosis or deformity, tumor contact with the common hepatic artery without showing tumor contact with the proper hepatic artery and/or celiac artery, and tumor contact with the superior mesenteric vein and/or portal vein including bilateral narrowing or occlusion without extending beyond the inferior border of the duodenum. Biological factors include potentially resectable disease based on anatomic criteria but with clinical findings suspicious for (but unproven) distant metastases or regional lymph nodes metastases diagnosed by biopsy or positron emission tomography-computed tomography. This also includes a serum carbohydrate antigen (CA) 19-9 level more than 500 units/ml. Conditional factors include the patients with potentially resectable disease based on anatomic and biologic criteria and with Eastern Cooperative Oncology Group (ECOG) performance status of 2 or more. The definition of BR-PDAC requires one or more positive dimensions (e.g. A, B, C, AB, AC, BC or ABC). The present definition acknowledges that resectability is not just about the anatomic relationship between the tumor and vessels, but that biological and conditional dimensions are also important. The aim in presenting this consensus definition is also to highlight issues which remain controversial and require further research.

The JPN Guidelines 2015 were prepared using the most up-to-date methods, and including the latest recommended medical treatments, and we are confident that this will make them easy for many clinicians to use, and will provide a useful tool in the decision-making process for the treatment of patients, and optimal medical support. The free mobile application and calculator for the JPN Guidelines 2015 is available via http://www.jshbps.jp/en/guideline/jpn-guideline2015.html.

The prognosis of pancreatic cancer is defined by the histology and extent of disease. Preoperative histologic diagnosis and diagnostic imaging are fundamentals in managing the disease, but it is not rare to find unexpected peritoneal dissemination or liver metastasis at the time of operation. The overall resectability rate of pancreatic cancer is 40% in Japan. Resecting the portal vein and peripancreatic plexus were performed on 40% of the patients who underwent pancreatectomy for invasive cancer in the head of the pancreas. Long-term survival was only found in patients who underwent pancreatectomy. Radical lymph node dissection, or combined resection of the large vessels, did not seem to improve survival further than the standard resection. Multidisciplinary treatments combined with surgery were performed, and various effects of postoperative chemotherapy after pancreatectomy, intraoperative- and postoperative-radiation therapy, or postoperative chemotherapy for unresectable tumor, were shown. Development of unconventional therapies and refinement of the conventional therapy should be promoted on a randomized prospective trial basis. To promote this effort, which requires the international comparisons and cooperation, JPS developed a computerized JPS registration system downloadable from the JPS website (http://www.kojin.or.jp/suizou/index.html).

The survival probability in patients with resected bile duct cancer was not significantly different between the gemcitabine adjuvant chemotherapy group and the observation group. Registration number: UMIN 000000820 (http://www.umin.ac.jp/).