Case Report
Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Nov 7, 2016; 22(41): 9222-9228
Published online Nov 7, 2016. doi: 10.3748/wjg.v22.i41.9222
Two cases of pancreatic ductal adenocarcinoma with intrapancreatic metastasis
Yusuke Fujita, Minoru Kitago, Yohei Masugi, Osamu Itano, Masahiro Shinoda, Yuta Abe, Taizo Hibi, Hiroshi Yagi, Yoko Fujii-Nishimura, Michiie Sakamoto, Yuko Kitagawa
Yusuke Fujita, Minoru Kitago, Osamu Itano, Masahiro Shinoda, Yuta Abe, Taizo Hibi, Hiroshi Yagi, Yuko Kitagawa, Department of Surgery, Keio University School of Medicine, Shinjuku-ku, Tokyo 160-8582, Japan
Yohei Masugi, Yoko Fujii-Nishimura, Michiie Sakamoto, Department of Pathology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan
Author contributions: Fujita Y, Kitago M and Masugi Y wrote the paper; Masugi Y, Fujii-Nishimura Y and Sakamoto M evaluated the pathological findings; all other members equally contributed medical treatment.
Institutional review board statement: The report was approved by the Keio University Hospital Institutional Review Board.
Informed consent statement: The patients provided informed written consent prior to therapy.
Conflict-of-interest statement: All authors declare there are no conflicts-of-interest related to this article.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Minoru Kitago, MD, PhD, Department of Surgery, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan. dragonpegasus@a3.keio.jp
Telephone: +81-3-53633802 Fax: +81-3-33554707
Received: July 12, 2016
Peer-review started: July 13, 2016
First decision: August 19, 2016
Revised: September 4, 2016
Accepted: September 14, 2016
Article in press: September 14, 2016
Published online: November 7, 2016
Abstract

There are no standardized diagnostic criteria for intrapancreatic metastasis of pancreatic ductal adenocarcinoma (PDAC). Here, we report two cases of patients with PDAC who were pathologically diagnosed as harboring intrapancreatic metastasis. In both cases, the main lesions were located in the pancreatic body, and no other lesion was detected preoperatively. The patients were diagnosed with pancreatic body cancers and distal pancreatectomy was performed. Pathological findings revealed microscopic cancer nests, which had connections to neither the main lesion nor the premalignant lesion in the pancreatic tail parenchyma. In both cases, the histological type of the daughter lesion was quite similar to that of the main lesion. Hence, we diagnosed the daughter lesions as metastatic foci in the pancreas. Although intrapancreatic metastasis of PDAC has been regarded as a poor prognostic factor, few reports of intrapancreatic metastasis are available. This article reports two such cases and provides a review of the literature.

Keywords: Carcinoma, Pancreatic ductal, Neoplasm micrometastasis, Recurrence, Carcinogenesis

Core tip: Although intrapancreatic metastasis (IPM) of pancreatic ductal adenocarcinoma has been regarded as a poor prognostic factor, few reports of IPM are available. Furthermore, the diagnostic criteria and the clinicopathological significance of IPM still need to be clarified. It should be remembered that IPM is present at a constant rate, and may be located in the remnant pancreas or in resected specimens other than the main lesion. IPM could be a cause of early recurrence. Here, we have presented two cases of IPM and provided suggestions regarding the foundation of the diagnosis of IPM.