A possible error in the interpretation of gastric carcinoma.

Isolated clusters of pyloric cells having homogeneous, eosinophilic (i.e., "glassy") cytoplasm were present in 6 (18.2%) of 33 consecutive gastrectomy specimens. Clusters with "glassy" cells displayed either a glandular arrangement or appeared as cohesive clusters. Cohesive clusters could be misinterpreted as signet-ring cell adenocarcinoma. However, remnants of the apical mucous secretion from the "ordinary" pyloric cells, the nuclei usually near the free border of the cells, as well as the negative reaction in the "glassy" cytoplasm for neutral and acid mucins, helped to differentiate them from signet-ring adenocarcinoma cells.