Gastrointestinal Stromal Tumors: A Retrospective Study at a Tertiary Care Center in Saudi Arabia in the Last Decade

TL;DR

This study examines gastrointestinal stromal tumors in Saudi Arabia over ten years, finding they mostly affect older males and are commonly located in the stomach.

Contribution

The study provides insights into the epidemiology and risk factors of GISTs in Saudi Arabia, emphasizing regional patterns and tumor characteristics.

Findings

Most GISTs were located in the stomach and were low-grade and nonmetastatic.

Tumor size varied significantly with risk categories, with high-risk tumors being much larger.

Anatomical location and risk assessment were significant predictors of tumor size.

Abstract

Introduction: Gastrointestinal stromal tumors (GISTs) are a significant subset of mesenchymal tumors primarily found in the gastrointestinal tract, impacting diagnostic and therapeutic approaches. Understanding their epidemiology is crucial for improving patient care and advancing treatment strategies.

Methodology: Our study at a Saudi tertiary hospital analyzed 50 patients with GIST, focusing on demographics, tumor locations, and risk assessments. We examined predictors of tumor size, including mitosis frequency, and assessed the impact of anatomical location and risk on clinical outcomes using RStudio software (Posit, Boston, MA).

Results: Among 50 patients with GIST, 36 (72.0%) were male with a median age of 60.5 years, and most tumors (33, 66.0%) were in the stomach. Risk assessments categorized tumors as follows: 20 (40.0%) low risk, 12 (24.0%) high risk, 7 (14.0%) moderate risk, 7 (14.0%) very low risk, and 4 (8.0%) no risk. Most tumors were low-grade (41, 82.0%) and nonmetastatic (47, 94.0%), predominantly spindle cell type (37, 74.0%). Tumor size varied significantly across risk categories: high-risk tumors averaged 10.3 cm versus 0.5 cm for no risk and 3.5 cm for very low risk (P < 0.001). Mitosis frequency differed significantly by risk category and tumor grade (P < 0.001). Tumor grade varied notably with risk categories and morphologic types, especially high-grade tumors in high-risk groups (8, 66.7%) and epithelioid tumors (2, 100%). Multivariable analysis identified predictors of tumor size: anatomical location (extra-GI, intra-abdominal; beta = 7.08, P = 0.011) and risk assessment (low risk, beta = 6.91, P = 0.001; moderate risk, beta = 11.2, P < 0.001; high risk, beta = 8.93, P < 0.001). Liver metastasis did not differ significantly across gender, anatomical location, risk assessment, or tumor grade.

Conclusions: In Saudi Arabia, GISTs predominantly affect males and are primarily located in the stomach. Our findings highlight significant variations in tumor size and grade based on risk assessments and anatomical location. Most GISTs were low-grade, nonmetastatic, and spindle cell type, emphasizing the need for enhanced research to improve diagnostics, tailor treatments, and optimize outcomes in the region.

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