International Surgery Journal | October 2019 | Vol 6 | Issue 10 Page 3513 International Surgery Journal Dahshan MEE et al. Int Surg J. 2019 Oct;6(10):3513-3520 http://www.ijsurgery.com pISSN 2349-3305 | eISSN 2349-2902 Original Research Article Outcome and prognostic factors of primary gastrointestinal stromal tumours following complete surgical resection Mohamed Ebrahim El Dahshan*, Mohamed Ali Mlees, Nehal Mohamed Elmashad, Hossam Ramadan Moussa, Ahmed Atia Darwish INTRODUCTION Although rare, gastrointestinal stromal tumors (GISTs) are the most common mesenchymal neoplasms, accounting for 1-2% of all neoplasms of the digestive tract. 1 They are derived from malignant transformation of the interstitial cells of Cajal, c-KIT-positive cells of neuroendocrine origin that function as the pacemaker in peristalsis. 2 Only 70% of patients with GISTs are symptomatic. Initial diagnosis may be difficult as symptoms and signs are often nonspecific; such as nausea, vomiting, vague abdominal discomfort, weight loss and early satiety. Bleeding due to erosion into the GI lumen may lead to patients presenting with hematemesis, melena or anemia. Rupture of a GIST can result in acute abdominal pain presenting as a surgical emergency. 3 ABSTRACT Background: Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal neoplasms. Surgical excision is the definitive treatment for primary localized GISTs. Targeted therapy represented by tyrosine kinase inhibitors has clearly improved the survival rates in patients with GISTs. The aim of this study was to identify prognostic factors influencing tumor recurrence and survival after curative resection of primary GISTs. Methods: This study was conducted on thirty seven patients with localized primary GIST who were operated on in the Department of General Surgery. Then completed adjuvant therapy in the medical Oncology Department, Faculty of Medicine; Tanta University Hospital, from March 2016 to August 2017. All patients’ data, clinical presentations, radiological and endoscopic data, surgical procedures, complications, and survival data were collected, reviewed and analyzed. Results: The mean age of the studied cases was 53.62 years. 14 patients were males and 23 patients were females. Eleven patients had performance status 2. Abdominal pain was the most common complaint. 4 patients presented with acute intestinal obstruction. Ileum was the most common site (14 cases) followed by stomach (13 cases). We reported four cases of extra-gastrointestinal stromal tumors (EGISTs). According to the mitotic index in studied cases; sixteen patients had mitotic count ˃5/50 HPF. Surgical excision was done in all cases with histopathologically negative resection margins. Thirty three cases showed good complete response without local recurrence or distant metastasis. Conclusions: Performance status of patients, tumor size and mitotic index were independent prognostic predictors for tumor recurrence or metastasis. Keywords: Outcome, Prognostic factors, Gastrointestinal stromal tumours, Resection Department of Surgery, Faculty of Medicine, Tanta University Hospital, Tanta, Egypt Received: 19 July 2019 Accepted: 06 September 2019 *Correspondence: Dr. Mohamed Ebrahim El Dahshan, E-mail: dr.eldahshan85@gmail.com Copyright: © the author(s), publisher and licensee Medip Academy. This is an open-access article distributed under the terms of the Creative Commons Attribution Non-Commercial License, which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited. DOI: http://dx.doi.org/10.18203/2349-2902.isj20194401