Gastric signet-ring cell lymphoma with alpha heavy chains.

Signet-ring cell lymphomas are rare especially as primary gastric tumours; alpha chain disease of the stomach is also unusual. A case of gastric signet-ring cell lymphoma with free alpha chains in the gastro-duodenal juice is reported and its light microscopic, immunohistological and ultrastructural features are described. Although the morphogenesis of signet-ring cell lymphoma is not clear, the present case showed many of the features of a mucosa-associated lymphoma. This rare variant of follicle centre cell lymphoma may easily be mistaken for a signet-ring cell carcinoma. A search for abnormal immunoglobulins should be made in serum, secretions or tissues in future cases of signet-ring cell lymphoma.