Virginia Research Day 2022

Medical Resident Research Case Reports

09 It’s Not Just A Tumor: It’s A GIST Tumor

Faryal Mirza, MD; Akintunde Akinleye, MD; and Tara Mancl, MD Corresponding author: Faryal.mirza@lpnt.net

SOVAH Health Internal Medicine Residency Program

Introduction: Gastrointestinal stromal tumors (GIST) are rare (<1%) mesenchymal neoplasms of the gastrointestinal tract. Most GISTs are related to mutations in either tyrosine kinase receptor or platelet-derived growth factor receptor alpha. Case Report: 70-year-old man with hypertension, coronary artery disease, Insulin dependent diabetes mellitus type 2, Benign Prostatic Hypertrophy, and previous venous thromboembolism presented with 6 months history of diffuse abdominal pain, and a 30lbs weight loss with no other GI symptoms. Family History: Non-contributory. Social History: No alcohol, tobacco, or illicit drug use. Allergies: ciprofloxacin and morphine caused hives. Review of System: Negative except abdominal pain and weight loss. Pertinent Physical Exam: BP 121/66, pulse 80, respirations 22, temp 98.7, oxygen saturation 98% on room air, taut abdomen with

particularly the role of c-KIT, cellular receptor for tyrosine kinase, which is also known as the stem factor receptor (CD117). Historically, 70-80% of GISTs were thought to be benign. However, all GIST tumors are now considered to have malignant potential and are no longer classified as benign. Tumors <5cm are usually low risk while those >5cm are often malignant. Larger GISTs (>10 cm) occurring anywhere, tend to be malignant. Mutations in c-KIT exon 11 mutations are more common in larger tumors with a worse prognosis than other mutations. Surgical resection (48-65% five- year survival) of the local disease is the gold standard therapy. GISTs are soft and fragile therefore, tumor rupture must be avoided when being removed to avoid potential surgical site spread. Conclusion: Gastrointestinal stromal tumors, while rare, are often malignant, and present with few specific symptoms till advanced. Early recognition and diagnosis are essential for optimal outcomes.

mild distension and moderate tenderness on palpation. Pertinent Initial Lab: White blood cells 11.4, hemoglobin 6.7, hematocrit 23.4, MCV 70.5, creatinine 1.2 with normal electrolytes. Patient received one unit of packed red blood cells in the ED. Abdomen/pelvic CT scan demonstrating multiple liver masses and large abdominal mass measuring 17 x 19 cm in size. He was admitted and had upper GI endoscopy revealing a greater curvature gastric mass. Biopsies of the stomach mass and liver lesions demonstrated GIST. He underwent partial gastrectomy, distal pancreatectomy, and splenectomy. Hospital course was complicated by pneumonia. Resected tumor mutation analysis revealed c-KIT exon 11 mutation. He began an outpatient course of Imatinib as palliative therapy. Restaging CT- chest/ abdominal/pelvis 1 month later demonstrated stable disease. Imatinib was continued. He was stable at last clinic visit. Discussion: GISTs are unique since they can range from benign to malignant in nature. Much of present understanding of GIST biology stems from identification of its molecular basis,

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