Differential Diagnosis for a Subepithelial Mass in the Gastric Fundus with Oozing Central Ulceration

• Single Most Likely Diagnosis
  • Gastrointestinal Stromal Tumor (GIST): This is the most likely diagnosis due to the location in the gastric fundus and the presence of a subepithelial mass with central ulceration. GISTs are known to occur in the stomach and can present with ulceration and bleeding.
• Other Likely Diagnoses
  • Gastric Carcinoid Tumor: These tumors can present as subepithelial masses and may ulcerate, leading to bleeding. They are less common than GISTs but should be considered in the differential diagnosis.
  • Gastric Leiomyoma: Although less common than GISTs, gastric leiomyomas can also present as subepithelial masses with ulceration and are a consideration in this scenario.
• Do Not Miss Diagnoses
  • Gastric Lymphoma: Although less likely, gastric lymphoma can present with a mass and ulceration. Missing this diagnosis could have significant implications for treatment and prognosis, making it a "do not miss" diagnosis.
  • Metastatic Disease: Metastases to the stomach from other primary sites (e.g., breast, lung, or melanoma) can present as subepithelial masses with ulceration. Given the potential for metastatic disease to significantly alter management, it is crucial not to miss this diagnosis.
• Rare Diagnoses
  • Gastric Glomus Tumor: A rare tumor that can present as a subepithelial mass, potentially with ulceration. While rare, it should be considered in the differential diagnosis, especially if other diagnoses are ruled out.
  • Gastric Paraganglioma: An extremely rare tumor that could present similarly, making it a consideration in the differential diagnosis of a subepithelial gastric mass with ulceration.