Gastrointestinal stromal tumours at the university of nigeriateaching hospital Enugu, Nigeria: an immunohistochemical study of gitmesenchymal tumours

Abstract

Mesenchymal tumours of the gastrointestinal tract (GIT) are uncommon. Recent progress in the understanding  of the biology and origin of these tumours has led to their reclassification. A new subclass designated Gastrointestinal Stromal Tumours (GIST) is diagnosed based on the presence of a mutational over expression of c-kit protein that is thought to be critical in the pathogenesis of these tumours.This newclass of tumoursmay form the majority of gastrointestinal mesenchymal tumours. Even though the diagnosis of GIST is mainly based on positive staining with CD117, a minority of tumours with histological characteristics of GIST are CD117 negative and are classified asCD117 negativeGIST. In this first reviewof mesenchymalGITtumours fromNigeria,we present 11 cases ofmesenchymal tumours of the gastrointestinal tract seen within a six-year period at our centre. Immunohistochemistry was performed on 7 of themin which histological appearances suggested GIST. Only two cases had all the criteria defined in the consensus conference on the diagnosis ofGIST. Our findings, albeit in a very small sample, contrastswith what obtains in developed countries in the proportion of GIT mesenchymal tumours that are truly GIST. This raises a question to be answered on the true nature and proportion of gastrointestinal strumal tumours among GITtumours inNigerian patients.

Keywords: Gastrointestinal, Stromal, Mesenchymal, Immunohistochemistry.