Gastrointestinal Pathology I Case Studies


CASE 4: Gastric adenocarcinoma


Clinical History:

A 60-year-old man complained of anorexia, vomiting, and vague abdominal pain accompanied by weight loss of 15 kg over the past two months. Physical examination revealed supraclavicular lymphadenopathy. An abdominal CT scan revealed that the stomach wall was thickened (image 4.1). He became progressively cachectic and died. At autopsy, the stomach was diffusely thickened and leather-like (image 4.2). Microscopic sections of the gastric wall are shown in images 4.3 and 4.4.
  1. What is the diagnosis?

    2. This is poorly differentiated gastric adenocarcinoma, diffuse type (linitis plastica). The neoplasm is not even forming glands, and some of the cells have a "signet ring" appearance.

  2. What are some predisposing factors for this lesion?

    3. Predisposing factors include chronic atrophic gastritis, a diet high in salt or nitrates, and decreased green leafy vegetables and fruits. Persons living in Japan have a much higher incidence of gastric cancer than persons in the U.S., where the incidence of stomach cancer has been falling for decades.

    Helicobacter pylori infection may play a role. The prevalence of H. pylori may depend upon diet and food storage and handling. H. pylori is a gram-negative bacterium residing under microaerobic conditions in a neutral microenvironment between the mucus and the superficial columnar mucosal cells. The organisms stimulate cytokine production by epithelial cells that recruit and activate immune and inflammatory cells in the underlying lamina propria, causing chronic active gastritis. This infection is generally considered to be acquired in childhood, but the inflammatory changes progress throughout life. Only a minority of persons with H. pylori infection develop peptic ulcer disease or gastric malignancy, but many persons are infected. H. pylori strains that possess the cag pathogenicity island induce more severe gastritis and augment the risk for developing peptic ulcer disease and gastric cancer. An inappropriate host immune response to the infection may play a role in development of gastric lesions.
  3. What is the typical prognosis?

    4. The prognosis in this case is poor. Overall, the 5-year survival for gastric cancer in the U.S. is only about 10 to 15%. In Japan, the prognosis is better because more gastric adenocarcinomas are detected as early gastric carcinomas.