Editorial
Copyright ©The Author(s) 2017. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Jul 21, 2017; 23(27): 4856-4866
Published online Jul 21, 2017. doi: 10.3748/wjg.v23.i27.4856
Current research and treatment for gastrointestinal stromal tumors
Kheng Tian Lim, Kok Yang Tan
Kheng Tian Lim, Kok Yang Tan, Department of Surgery, Khoo Teck Puat Hospital, Singapore 768828, Singapore
Author contributions: Lim KT and Tan KY contributed equally to this paper in every aspect from design to writing.
Conflict-of-interest statement: Lim KT and Tan KY declare no conflicts of interest related to this publication.
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: Kheng Tian Lim, MB BCh BAO, LRCP and SI (Hons), MCh, FRCS (Gen Surg), Consultant Surgeon, Department of Surgery, Khoo Teck Puat Hospital, 90 Yishun Central, Singapore 768828, Singapore. lim.kheng.tian@alexandrahealth.com.sg
Telephone: +65-66024737 Fax: +65-66023648
Received: February 28, 2017
Peer-review started: March 2, 2017
First decision: April 21, 2017
Revised: May 11, 2017
Accepted: June 18, 2017
Article in press: June 19, 2017
Published online: July 21, 2017
Processing time: 141 Days and 12.5 Hours
Abstract

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the gastrointestinal tract and have gained considerable research and treatment interest, especially in the last two decades. GISTs are driven by mutations commonly found in the KIT gene and less commonly in the platelet-derived growth factor receptor alpha gene, BRAF gene and succinate dehydrogenase gene. GISTs behave in a spectrum of malignant potential, and both the tumor size and mitotic index are the most commonly used prognostic criteria. Whilst surgical resection can offer the best cure, targeted therapy in the form of tyrosine kinase inhibitors (TKIs) has revolutionized the management options. As the first-line TKI, imatinib offers treatment for advanced and metastatic GISTs, adjuvant therapy in high-risk GISTs and as a neoadjuvant agent to downsize large tumors prior to resection. The emergence of drug resistance has altered some treatment options, including prolonging the first-line TKI from 1 to 3 years, increasing the dose of TKI or switching to second-line TKI. Other newer TKIs, such as sunitinib and regorafenib, may offer some treatment options for imatinib-resistant GISTs. New molecular targeted therapies are being evaluated, such as inhibitors of BRAF, heat shock protein 90, glutamine and mitogen-activated protein kinase signaling, as well as inhibitors of apoptosis proteins antagonist and even immunotherapy. This editorial review summarizes the recent research trials and potential treatment targets that may influence our future patient-specific management of GISTs. The current guidelines in GIST management from Europe, North America and Asia are highlighted.

Keywords: Gastrointestinal stromal tumors; KIT gene; Platelet-derived growth factor receptor alpha gene; BRAF gene; Succinate dehydrogenase gene; CD117; Tyrosine kinase inhibitor; Molecular targeted therapy

Core tip: Research in the histogenesis of gastrointestinal stromal tumors (GISTs) identified gene mutations in KIT, platelet-derived growth factor receptor alpha and BRAF. The discovery of tyrosine kinase inhibitors (TKIs) has allowed targeted therapy in metastatic and high-risk resected GISTs. However, the emergence of TKI-resistant GISTs has raised some important treatment issues. Newer TKIs and alternative targeted therapy within the domain of BRAF and the mitogen-activated protein kinase signaling pathway, heat shock protein 90 and succinate dehydrogenase inhibition are being investigated and appear promising. Many clinical trials have been undertaken and are still ongoing to define the best molecular targeted therapy for GISTs. The European, American and Asian guidelines on GISTs provide useful resources for specialists dealing with these interesting tumors.