Case Report
Copyright ©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Clin Cases. Apr 16, 2021; 9(11): 2641-2648
Published online Apr 16, 2021. doi: 10.12998/wjcc.v9.i11.2641
Combined immune checkpoint inhibitors of CTLA4 and PD-1 for hepatic melanoma of unknown primary origin: A case report
An-Che Cheng, Yi-Jia Lin, Sung-Hua Chiu, Yu-Lueng Shih
An-Che Cheng, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei 114, Taiwan
Yi-Jia Lin, Department of Pathology, Tri-Service General Hospital, National Defense Medical Center, Taipei 114, Taiwan
Sung-Hua Chiu, Department of Radiology, Tri-Service General Hospital, National Defense Medical Center, Taipei 114, Taiwan
Yu-Lueng Shih, Department of Internal Medicine, Division of Gastroenterology, Tri-Service General Hospital, National Defense Medical Center, Taipei 114, Taiwan
Author contributions: Cheng AC collected the clinical information and reviewed and drafted the manuscript; Lin YJ collected and interpreted the pathological findings; Chiu SH analyzed and interpreted the imaging findings; Shih YL revised the manuscript for important intellectual content; all authors read and approved the final manuscript.
Informed consent statement: Informed written consent was obtained from the patient for publication of this report and any accompanying images.
Conflict-of-interest statement: The authors declare that they have no conflict of interest to disclose.
CARE Checklist (2016) statement: The authors have read the CARE Checklist (2016), and the manuscript was prepared and revised according to the CARE Checklist (2016).
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (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/
Corresponding author: Yu-Lueng Shih, PhD, Academic Research, Associate Professor, Attending Doctor, Department of Internal Medicine, Division of Gastroenterology, Tri-Service General Hospital, National Defense Medical Center, No. 325 Section 2, Cheng-Kung Road, Neihu, Taipei 114, Taiwan. albreb@ms28.hinet.net
Received: December 12, 2020
Peer-review started: December 12, 2020
First decision: December 17, 2020
Revised: January 1, 2021
Accepted: February 22, 2021
Article in press: February 22, 2021
Published online: April 16, 2021
Processing time: 110 Days and 20.7 Hours
Abstract
BACKGROUND

Melanoma is uncommonly found in lymph nodes, subcutaneous tissue, or visceral organs without a primary lesion, where it is identified as metastatic melanoma with unknown primary (MUP). Hepatic MUP is extremely rare and has a poor prognosis. There is limited information on its pathogenesis, clinical and imaging features, and pathological findings. There are no guidelines for the use of immune checkpoint inhibitors (ICIs) in hepatic MUP, and the treatment outcome has rarely been reported.

CASE SUMMARY

A 42-year-old woman presented to our hospital with hepatic tumors found incidentally during a routine check-up. Contrast-enhanced abdominal com-puterized tomography showed multiple mass lesions in the liver. Pathological results revealed melanoma, which was confirmed by immunohistochemical staining for HMB-45(+), Melan-A(+), S-100(+), and SOX10(+). There was no evidence of primary cutaneous, ocular, gastrointestinal, or anal lesion on a comprehensive examination. The patient was diagnosed with hepatic MUP. She received combined antibodies against cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4, ipilimumab) and programmed death protein-1 (PD-1, nivolumab). She died of hepatic failure 9 mo after hepatic MUP was diagnosed. This the first case of hepatic MUP treated with combined ipilimumab and nivolumab, who showed better outcome than previous cases.

CONCLUSION

Combined ICIs of PD-1 and CTLA-4 may be considered as the first-line therapy for patients with hepatic MUP.

Keywords: Metastatic melanoma with unknown primary; Liver metastasis; Immune checkpoint inhibitor; Programmed death protein-1; Cytotoxic T-lymphocyte-associated antigen 4; Case report

Core Tip: Hepatic metastatic melanoma with an unknown primary site (MUP) is extremely rare and there is limited information on its pathogenesis, clinical and imaging features, pathological findings, and treatment outcome. There are no guidelines for the use of immune checkpoint inhibitors (ICIs) in hepatic MUP. We report the first case of hepatic MUP treated with combined ICIs of cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) and programmed death protein-1 (PD-1), describing the clinical features, imaging, pathological findings, and outcome. This case showed better treatment outcome than previous cases of hepatic MUP. Combined ICIs of PD-1 and CTLA-4 may be considered as the first-line therapy for patients with hepatic MUP.