Differential Diagnosis for Gastric Mass on CT Scan

Given the patient's presentation with a gastric mass on CT scan, no weight loss, and no change in appetite, the following differential diagnoses are considered:

• Single Most Likely Diagnosis
  • GIST (Gastrointestinal Stromal Tumor): This is often the most common diagnosis for a gastric mass, especially if the patient does not have systemic symptoms like weight loss. GISTs can be asymptomatic and discovered incidentally during imaging for other reasons.
• Other Likely Diagnoses
  • Gastric Carcinoma: Although less likely without symptoms like weight loss, gastric carcinoma remains a possibility, especially in older adults or those with risk factors such as Helicobacter pylori infection or a family history of gastric cancer.
  • Leiomyosarcoma: A type of smooth muscle tumor that can occur in the stomach. It might not cause significant symptoms early on, making it a consideration in the differential diagnosis.
  • Gastric Lymphoma: This can also present as a mass in the stomach. While it might be less common than other diagnoses, it's a consideration, especially if the patient has systemic symptoms or risk factors for lymphoma.
• Do Not Miss Diagnoses
  • Gastric Carcinoma with Early Stage: Even though the patient does not have weight loss or change in appetite, early-stage gastric carcinoma might not produce significant symptoms. Missing this diagnosis could lead to delayed treatment and a worse prognosis.
  • Metastasis to the Stomach: Although rare, metastasis from other primary cancers (like breast, lung, or melanoma) to the stomach can occur and should not be missed, as it significantly alters the treatment approach and prognosis.
• Rare Diagnoses
  • Carcinoid Tumor: A type of neuroendocrine tumor that can occur in the stomach. These are generally rare and might not cause significant symptoms unless they produce hormones.
  • Gastric Schwannoma: A benign tumor arising from the nerve sheath. It's rare in the stomach and usually asymptomatic but can be considered in the differential diagnosis of a gastric mass.

Each of these diagnoses has different implications for treatment and prognosis, highlighting the importance of a thorough diagnostic workup, including biopsy and further imaging as necessary, to determine the exact nature of the gastric mass.