P-187 - GIST- Retrospective analysis of a district hospital

Abstract

Introduction: Gastrointestinal stromal tumors (GISTs) are rare mesenchymal tumors that arise predominantly in the gastrointestinal tract. Methods: Retrospective analysis of 35 patients diagnosed based on the histology and immunohistochemistry of a biopsy or resection of a specimen from 2002 to 2015 at our hospital. Results: 54% of the patients were males and the mean age was 65.2 years. The gastric involvement occurred in nineteen cases (54.3%), small intestine in ten cases (28.6%), uterus and rectum both in two cases (5.7%) and two cases located in the lymphatic system, without the finding of primary tumor (5.7%). Ten cases were diagnosed in an emergency setting (hemorrhagic or in occlusion of organs). Three patients had a diagnostic biopsy without surgical resection as a curative procedure. A spindle cell pattern was present in twenty-eight of the specimens examined, epithelioid in two and a mixed pattern in five. All specimens were positive for CD117 and in 80% of cases for CD34. All patients with low and very low risk of progression survive for 1 to 5 years free of disease. Of the thirteen patients with a high degree of malignancy, two died postoperatively, five died within a year of dissemination, the other patient survived for more than five years postoperatively with tyrosine kinase inhibitors. Conclusion: GISTs are the most common mesenchymal tumors. Surgery is the primary treatment of choice in localized or potentially resectable GIST. The surgery in conjunction with Imatinib form the first-line therapy being its curative efficacy for the majority of patients already demonstrated.