Table of Contents
ISRN Gastroenterology
Volume 2012 (2012), Article ID 595968, 16 pages
http://dx.doi.org/10.5402/2012/595968
Review Article

Gastrointestinal Stromal Tumors: A Review of Case Reports, Diagnosis, Treatment, and Future Directions

1Department of Internal Medicine, Nassau University Medical Center, East Meadow, NY 11554, USA
2Department of Gastroenterology, Nassau University Medical Center, East Meadow, NY 11554, USA

Received 13 January 2012; Accepted 5 February 2012

Academic Editors: A. Amedei and C.-T. Shun

Copyright © 2012 Christopher B. Tan et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Gastrointestinal stromal tumor (GIST) is a nonepithelial, mesenchymal tumor first described by Mazur and Clark in 1983. Since then, its molecular biology has been studied in great detail. Special interest in the role of tyrosine kinase in its regulation has been the target by different drug research. Mutation in ๐‘ -kit exons 9, 11, 13, 17 and PDGFRA mutation in exons 12, 14, 18 are responsible for activation of gene signaling system resulting in uncontrolled phosphorylation and tissue growth. However, 5 to 15% of GISTs does not harbor these mutations, which raises additional questions in another alternate signaling pathway mutation yet to be discovered. Diagnosis of GISTs relies heavily on KIT/CD117 immunohistochemical staining, which can detect most GISTs except for a few 3% to 5% that harbors PDGFRA mutation. Newer staining against PKC theta and DOG-1 genes showed promising results but are not readily available. Clinical manifestation of GISTs is broad and highly dependent on tumor size. Surgery still remains the first-line treatment for GISTs. The advancement of molecular biology has revolutionized the availability of newer drugs, Imatinib and Sunitinib. Together with its advancement is the occurrence of Imatinib/Sunitinib drug resistance. With this, newer monoclonal antibody drugs are being developed and are undergoing clinical trials to hopefully improve survival in patients with GISTs.