Table 2: Characteristics of gastric carcinoid tumors.

Type IType IIType III

Proportion of gastric carcinoids70%–80%—most commonLess than 5%15%–20%
AssociationsChronic atrophic gastritis, pernicious anemiaMEN-1, Zollinger-Ellison syndromeSporadic carcinoid syndrome
EpidemiologyTypically women 50–70 yrs oldFamily history of MEN-1 syndromeIncreased in African Americans, most common in men
Plasma gastrin levelsHighHighNormal
Gastric acid outputLowHighNormal
Number of tumoursMultipleMultipleSingle
Size of tumors<1 cm<1 cm2–5 cm
Site of tumorsFundusFundus (occasionally antrum)Fundus or antrum
Mean age at diagnosis635055
PrognosisGoodUsually good—a minority of tumors are more aggressive Poor