Introduction: Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal neoplasms of the gastrointestinal system.
Histopathological and immunochemistry examination takes an important part in confirming the types of GISTs, to choose appropriate therapeutics
for patients. Patients demographics, anatomic sites, histopathology and immunochemistry characteristics of GISTs are unknown in St Francis
Hospital Nsambya (SFHN) and Uganda Cancer Institute (UCI).
Objectives: This study aimed to explore the demographics, anatomic sites, histopathological and immunochemical characteristics of GISTs in St
Francis Nsambya Hospital and Uganda Cancer institute.
Methodology: A cross sectional study was conducted. The study population included patients with a histological diagnosis of GISTs who presented
between 2018 to 2021 in both facilities. Clinical, pathological and immunochemistry data was collected and analyzed.
Results: A total of 146 records/blocks of patients were reviewed and out of these only Histology and immunochemistry was done on 81 blocks/
patients. Majority of the patients were aged 40 to 59years, (42%) and had a median age of 57 years with IQR (45-65). There was a male
predominance of 51.9%. The commonest tumor site was the stomach, (81.5%). The commonest histological type was spindle cell (79%) followed
by mixed (11.1%) then epithelioid 8 (9.9%). Most of cases in our study were benign (80.1%) and mitotic count ≤ 5/50 HPF in 71.6% cases. All cases
with low mitotic rate were mostly benign with a p value of <0.0001.
Conclusion: We found GISTs were more common in male gender, stomach being the commonest site and 19% of GISTs were below 40 years.
Spindle cell was the commonest histologic type and most of them were CKIT positive. Malignancy was correlated with non-spindle cell type and
high mitotic rate.