S1188 Cases of Gastrointestinal Stromal Tumor (GIST) Associated with Liver Abscesses: A Systematic Review

Introduction: Gastrointestinal stromal tumors (GISTs) are common subepithelial gastrointestinal (GI) tumors with different clinical presentations and are classified according to the risk of malignancy. Many case reports have documented the occurrence of liver abscesses in GIST, but the association with tumor pathology and presentation has not been documented. This systemic review aims to reveal the association of GIST as a cause or predisposing factor for liver abscesses. Methods: All included studies were extracted from Embase and Medline. Inclusion criteria are case reports or case series that confirmed a gastrointestinal stromal tumor associated with liver abscesses. We excluded case reports of a gastrointestinal stromal tumor without a liver abscess. All literature reviews, guidelines, and review articles were excluded from this study. Studies that were published in languages other than English were not included. We screened 54 articles and included 26 articles. Results: The patients had variable presentations from asymptomatic to sepsis. Tumors were found either in the stomach or in the small intestine, with or without abscess formation. Most GISTs were benign with a low mitotic index, and only two cases were malignant GISTs. In addition to the liver, abscesses can also be found in the tumor itself or in other parts of the GI tract. Eleven cases showed positive culture results from abscess drainage. Blood cultures and/or abscess cultures showed different types of certain streptococcus: S. Viridans, S. anginosus, S. Milleri, S intermedius, and S. constellatus. Ten cases showed multiple liver abscesses similar to metastasis from malignancies, and only seven cases had a single liver abscess. One case was malignant GIST. Abscesses were also found in the right and left lobes of the liver, but more often in the right lobe of the liver. This may be due to the relatively larger size of the right lobe. All cases are confirmed by positive CD117. The DOG1 gene was tested positive in 2 cases. All patients received broad-spectrum intravenous antibiotics with or without tumor resection. Conclusion: Liver abscesses with GIST are not uncommon. They are usually associated with hematogenous seeding in bacteremic patients, with the Streptococcus anginosus group being the predominant pathogen. Although infections may have a worse prognosis in patients with GI tumors, liver abscesses generally have a favorable outcome in GIST.Figure 1.: Shows a PRISMA flow chart of our literature search.Table 1.: Survey responses from medical professionals screening for HCC in Africa.