Giant gastric gastrointestinal stromal tumor (clinical case)

Background. Gastrointestinal stromal tumors (GISTs) are the most prevalent mesenchymal neoplasms of the gastrointestinal tract, although they account for only 1–2 % of all malignant tumors in the gastrointestinal tract. GISTs most commonly occur in individuals aged 40 to 80 and are primarily located in the stomach. Despite their low metastatic rate, GISTs can invade adjacent tissues, leading to significant clinical symptoms. Diagnosing these tumors is challenging and relies on microscopic and immunohistochemical examinations. This paper presents a clinical case of a patient with a giant gastric GIST, highlighting the importance of timely and accurate diagnosis for radical surgical intervention.

Clinical case. A 59‑year-old female patient, referred to as Patient N., presented to the medical center with a retroperitoneal mass that was discovered during an evaluation after an episode of detected tachycardia. Ultrasonography and further diagnostic imaging revealed a large, heterogeneous mass closely adhering to the gastric wall. Initial biopsies did not yield sufficient material for analysis, prompting a diagnostic laparoscopy, which confirmed the presence of a multinodular tumor consistent with a gastrointestinal stromal tumor (GIST) with high malignant potential. The patient was initiated on targeted therapy with Imatinib, but showed no signs of improvement. Consequently, an atypical gastrectomy and distal pancreatosplenectomy were performed. Post-operative confirmation of the GIST diagnosis was obtained. The patient continues with Imatinib targeted therapy to this day, with no signs of recurrence or disease progression observed.

Conclusion. This case highlights the complexity of treating patients with GISTs, particularly in the context of the tumor’s genetic characteristics. Successful surgical intervention in the treatment of gastric GISTs is crucial when targeted therapy proves ineffective. The results emphasize the importance of a personalized approach to treating such tumors, including mandatory molecular testing (c-KIT, PDGFRA). Although adjuvant treatment with imatinib is effective for patients with mutations in the KIT and PDGFRA genes, its benefits are lacking in patients without such mutations or with mutations causing resistance to therapy. This underscores the significance of an individualized approach in selecting a treatment strategy.

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