Pepsinogens I and II in gastric cancer: an immunohistochemical study using monoclonal antibodies.

Monoclonal antibodies were used to examine the immunohistochemical expression of pepsinogens I and II in 31 early and 76 advanced gastric cancers. Of the 107 carcinomas studied, 19 contained pepsinogen II and only 3, found exclusively in pepsinogen II-positive cases, contained pepsinogen I. Gastric cancer produces pepsinogen II more frequently than pepsinogen I, and production of the latter is significantly associated with the former. Histologically, there were 54 intestinal-type and 53 diffuse-type cancers. The former produced pepsinogen II more frequently than the latter. In the diffuse type, the four pepsinogen II-positive cases were found exclusively in females. Although the pepsinogen expression was independent of the macroscopic features in advanced gastric cancer, it was found that the protruded-type early gastric cancer produced pepsinogen II more frequently than the depressed type. Incidences of pepsinogen positivity were not different between early and advanced gastric cancers or between cancers with or without lymph node metastasis, suggesting that production of pepsinogen is independent of tumor growth.