Observational Study
Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Oct 14, 2016; 22(38): 8596-8604
Published online Oct 14, 2016. doi: 10.3748/wjg.v22.i38.8596
Pancreatic neuroendocrine tumor and solid-pseudopapillary neoplasm: Key immunohistochemical profiles for differential diagnosis
Yusuke Ohara, Tatsuya Oda, Shinji Hashimoto, Yoshimasa Akashi, Ryoichi Miyamoto, Tsuyoshi Enomoto, Kaishi Satomi, Yukio Morishita, Nobuhiro Ohkohchi
Yusuke Ohara, Tatsuya Oda, Shinji Hashimoto, Yoshimasa Akashi, Ryoichi Miyamoto, Tsuyoshi Enomoto, Nobuhiro Ohkohchi, Department of Gastrointestinal and Hepato-Biliary-Pancreatic Surgery, Faculty of Medicine, University of Tsukuba, Ibaraki 305-8575, Japan
Kaishi Satomi, Yukio Morishita, Department of Diagnostic Pathology, Faculty of Medicine, University of Tsukuba, Ibaraki 305-8575, Japan
Yukio Morishita, Diagnostic Pathology Division, Tokyo Medical University Ibaraki Medical Center, Ibaraki 305-0395, Japan
Author contributions: Ohara Y and Oda T designed the research, drafted and revised the paper; Hashimoto S, Akashi Y, Miyamoto R, Enomoto T and Ohkohchi N performed surgery and managed resected specimens; Satomi K and Morishita Y evaluated the pathological expression of the specimen.
Supported by Scientific Research KAKENHI, No. 23300362 and No. 23659635.
Institutional review board statement: This study was performed and reviewed in accordance with the ethics committee of University of Tsukuba Hospital.
Informed consent statement: All of the patients provided informed consent for analysis of their tissue samples in accordance with the ethics committee of University of Tsukuba Hospital.
Conflict-of-interest statement: The authors have no potential conflicts of interest to disclose.
Data sharing statement: No additional data are available.
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: Tatsuya Oda, MD, PhD, Department of Gastrointestinal and Hepato-Biliary-Pancreatic Surgery, Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8575, Japan. tatoda@md.tsukuba.ac.jp
Telephone: +81-298-533221 Fax: +81-298-533222
Received: May 5, 2016
Peer-review started: May 6, 2016
First decision: June 20, 2016
Revised: July 4, 2016
Accepted: August 1, 2016
Article in press: August 1, 2016
Published online: October 14, 2016
Processing time: 159 Days and 16.6 Hours
Abstract
AIM

To reveal better diagnostic markers for differentiating neuroendocrine tumor (NET) from solid-pseudopapillary neoplasm (SPN), focusing primarily on immunohistochemical analysis.

METHODS

We reviewed 30 pancreatic surgical specimens of NET (24 cases) and SPN (6 cases). We carried out comprehensive immunohistochemical profiling using 9 markers: Synaptophysin, chromogranin A, pan-cytokeratin, E-cadherin, progesterone receptor, vimentin, α-1-antitrypsin, CD10, and β-catenin.

RESULTS

E-cadherin staining in NETs, and nuclear labeling of β-catenin in SPNs were the most sensitive and specific markers. Dot-like staining of chromogranin A might indicate the possibility of SPNs rather than NETs. The other six markers were not useful because their expression overlapped widely between NETs and SPNs. Moreover, two cases that had been initially diagnosed as NETs on the basis of their morphological features, demonstrated SPN-like immunohistochemical profiles. Careful diagnosis is crucial as we actually found two confusing cases showing disagreement between the tumor morphology and immunohistochemical profiles.

CONCLUSION

E-cadherin, chromogranin A, and β-catenin were the most useful markers which should be employed for differentiating between NET and SPN.

Keywords: Neuroendocrine tumor; Pancreas; Solid-pseudopapillary neoplasm; Immunohistochemistry; Diagnosis

Core tip: Neuroendocrine tumor (NET) and solid-pseudopapillary neoplasm (SPN) are two types of pancreatic tumor that were sometimes confused in differential diagnosis. We reviewed 30 pancreatic surgical specimens of NET (24 cases) and SPN (6 cases). We carried out comprehensive immunohistochemical profiling using 9 markers. E-cadherin staining in NETs, and nuclear labeling of β-catenin in SPNs were the most sensitive and specific markers. Dot-like staining of chromogranin A might indicate the possibility of SPNs rather than NETs. Moreover, two cases that had been initially diagnosed as NETs on the basis of their morphological features, demonstrated SPN-like immunohistochemical profiles.