Clinical Significance of Insulin-Growth Factor 1 and Insulin-Growth Factor 1 Receptor Expression in Gastrointestinal Stromal Tumors

Background/Aims: Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors in the gastrointestinal tract and are mostly driven by KIT and PDGFRA-activation mutations. However, other signaling pathways are involved in pathogenesis and proliferation of GISTs. This study investigates the prognostic significance of insulin-like growth factor 1 (IGF1) and IGF1 receptor (IGF1R) and the role of succinate dehydrogenase subunit B (SDHB) in GISTs. Methodology: Immunohistochemistry (IHC) for IGF1, IGF1R and SDHB was performed in total of 165 GISTs. Results: The overexpression of IGF1 was evident in tumors with high mitotic count, large tumor size and was correlated with high risk of malignant behavior. IGF1R overexpression was correlated with IGF overexpression, high mitotic count and high risk of malignant behavior. Loss of expression for SDHB was found in only 2 gastric GISTs. Conclusions: The overexpression of IGF1 and IGF1R can be useful marker to predict relapse and aggressive behavior in GISTs and has prognostic implications.