Clinicopathologic features and prognostic grouping of gastrointestinal stromal tumors (GISTs) in Pakistani patients: an institutional perspective

Abstract

Objectives: Gastrointestinal stromal tumors (GISTs) are rare tumors of gastrointestinal tract, prognosis of which largely depends upon histopathologic characteristics of resection specimens, which were not widely studied in our population. Therefore we aimed to evaluate the histopathologic characteristics of GISTs in our population and their prognostic grouping according to college of American pathologist's guidelines.

Results: Mean age of patients was 53.4 years (18-71 years). 92% of cases were of primary GISTs and stomach was the most common site (57.7%). 75% of cases were of spindle cell morphology and 53.8% belonged to high risk prognostic group. Comparison of stomach and intestinal GISTs showed that intestinal GISTs were found to be of high grade (70%) and of high risk prognostic group (75 and 80%) compared to stomach GISTs (43% were of high risk prognostic group), however this finding was not statistically significant. GISTs are infrequent gastrointestinal tumors but early diagnosis and identification of adverse histological features are key to successful treatment. We found a large majority of GISTs to be located in stomach, however intestinal GISTs were found more likely to be associated with adverse prognostic parameters. However more large scale studies are warranted to establish this finding.

Keywords: Epitheloid GIST; GISTs; Gastrointestinal stromal tumors; Spindle cell GIST.

Fig. 1

Gastrointestinal stromal tumor, Epitheloid subtype: A–C H&E sections showing sheets of epitheloid cells with marked atypia. D Diffuse expression of CD117 noted in tumor cells