Lysozyme in human gastric carcinoma: a retrospective immunohistochemical study.

A total of 171 gastric carcinomas comprising 69 advanced cancers and 102 early cancers were examined immunohistochemically for lysozyme. Tumour cells containing lysozyme were detected in 65 cases or 38% of the 171 gastric cancer cases. The incidence of these cells did not differ remarkably by histological type and infiltrative growth of gastric carcinoma. Of the foregoing 65 cases, two well-differentiated adenocarcinomas and three signet ring cell carcinomas had numerous lysozyme-containing tumour cells, 13 had many argentaffin or argyrophil cells, and 40 had various amounts of several types of mucin. In addition, tumour cells containing both lysozyme and mucin could be identified. No correlation could be observed between lysozyme immunoreactivity in the tumour cells and cellular infiltration of granulocytes or macrophages around the tumour. The lysozyme appeared to be produced by tumour cells. The two year survival rates indicate a tendency for advanced gastric cancers containing lysozyme to have a poor prognosis.