Case Report
Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Nov 7, 2016; 22(41): 9229-9234
Published online Nov 7, 2016. doi: 10.3748/wjg.v22.i41.9229
Collision tumor of hepatocellular carcinoma and neuroendocrine carcinoma involving the liver: Case report and review of the literature
Gyu Ho Choi, Sun Young Ann, Soon Il Lee, Suk Bae Kim, Il Han Song
Gyu Ho Choi, Sun Young Ann, Soon Il Lee, Suk Bae Kim, Il Han Song, Dankook University College of Medicine, Cheonan 31116, South Korea
Author contributions: Choi GH and Ann SY collected the patients’ clinical data; Choi GH, Lee SI, Kim SB and Song IH designed the report and wrote the paper.
Institutional review board statement: This study was approved by the Institutional Review Board of Dankook University Hospital.
Informed consent statement: The patient was not required to give informed consent to this study because this study used the clinical data that was obtained after this patient agreed to treatment before initiation of treatment.
Conflict-of-interest statement: All authors declare 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: Suk Bae Kim, MD, Dankook University College of Medicine, 119 Dandae-ro, Dongnam-gu, Cheonan 31116, South Korea. dryakson@hanmail.net
Telephone: +82-41-5503910 Fax: +82-41-5563256
Received: June 2, 2016
Peer-review started: June 3, 2016
First decision: July 12, 2016
Revised: June 21, 2016
Accepted: August 23, 2016
Article in press: August 23, 2016
Published online: November 7, 2016
Processing time: 156 Days and 22.1 Hours
Abstract

Primary hepatic neuroendocrine carcinoma (NEC) with concurrent occurrence of hepatocellular carcinoma (HCC) of the liver is very rare. Only 8 cases have been reported in the literature. Concurrent occurrence of HCC and NEC in the liver is classified as combined type or collision type by histological distributional patterns; only 2 cases have been reported. Herein, we report a case of collision type concurrent occurrence of HCC and NEC, in which primary hepatic NEC was in only a small portion of the nodule, which is different from the 2 previously reported cases. A 72-year-old male with chronic hepatitis C was admitted to our hospital for a hepatic mass detected by liver computed tomography (CT) at another clinic. Because the nodule was in hepatic segment 3 and had proper radiologic findings for diagnosis of HCC, including enhancement in the arterial phase and wash-out in the portal and delay phases, the patient was treated with laparoscopic left lateral sectionectomy. The pathology demonstrated that the nodule was 2.5 cm and was moderately differentiated HCC. However, a 3 mm-sized focal neuroendocrine carcinoma was also detected on the capsule of the nodule. The tumor was concluded to be a collision type with HCC and primary hepatic NEC. After the surgery, for follow-up, the patient underwent a liver CT every 3 mo. Five multiple nodules were found in the right hepatic lobe on the follow-up liver CT 6 mo post-operatively. As the features of the nodules in the liver CT and MRI were different from that of HCC, a liver biopsy was performed. Intrahepatic recurrent NEC was proven after the liver biopsy, which showed the same pathologic features with the specimen obtained 6 mo ago. Palliative chemotherapy with a combination of etoposide and cisplatin has been administered for 4 months, showing partial response.

Keywords: Collision tumor; Hepatocellular carcinoma; Neuroendocrine carcinoma; Chronic hepatitis C

Core tip: Only 2 cases of collision tumor of hepatocellular carcinoma and primary hepatic neuroendocrine carcinoma involving the liver have been reported in the literature. This case shows different clinical characteristics from the previous cases. And we analyzed total 8 previous cases reported as concurrent occurrence of hepatocellular carcinoma and neuroendocrine carcinoma. This report will be helpful to elucidate the features of collision tumors.