Retrospective Analysis of Outcomes and Toxicity of Adjuvant Imatinib in Patients with Gastrointestinal Stromal Tumor in Clinical Oncology Department in Ain Shams University

Abstract

Abstract Background Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumor of the gastrointestinal (GI) tract. Most of them (>75%) are driven by an oncogenic initiating event involving activating mutations of the genes encoding for tyrosine kinase, KIT or platelet derived growth factor receptor alpha (PDGFRA). Efficacy of the tyrosine kinase Inhibitor imatinib is now well established for localized and advanced disease. For localized GISTs, 3 years treatment is the recommended adjuvant therapy for high risk patients. This review aims to describe current knowledge on the issue of adjuvant therapy of primary GISTs in view of available results and to further refine the definition of the population of GIST patients at high risk of relapse including molecular criteria Aim of the Work The purpose of this study is to retrospectively analyze the outcomes and toxicity of adjuvant Imatinib in patients with gastrointestinal stromal tumor Patients and Methods This study is a retrospective study that included 40 patients attending the sarcoma clinic at the Clinical Oncology Department, Ain Shams University during the period from 1 January 2016 till 31 December 2022. Results A total of 40 patients were included. Of whom 47.5% of patients completed 3 year duration of treatment by Imatinib, whereas those who didn't complete their 3 years treatment were presented by 52.5%. Higher DFS was found in those who completed their treatment duration in comparison to the second group with median DFS 67.8 vs 47.9 months respectively P value <0.003 highly significant. Imatinib was generally tolerated and toxicity was reported only in 20% of the study population, and the commonly found side effect was skin rash, followed by hematological toxicities then GIT manifestations. 22.5% of patients developed recurrence of the disease and higher rate of recurrence was found among elderly>60 years, tumor size>10 cm, and higher Ki67. Conclusion treatment with adjuvant Imatinib appears to be associated with higher DFS and we'll tolerated side effects