The diagnostic significance of sulfated acid mucin content in gastric intestinal metaplasia with early gastric cancer.

Specimens of fifteen surgically resected stomachs with early gastric cancer were histologically and histochemically examined using Alcian blue-periodic acid-Schiff and high iron diamine--Alcian blue stains. Samples were taken from the tumor, from the gastric mucosa 3 cm from the edge, and from the resected margins. In all 15 stomachs colonic intestinal metaplastic changes were present in the tumor tissue, as well as in the adjacent 3 cm mucosa and in the distant resected margins. In all cases neutral mucin content was reduced, whereas acid nonsulfated mucin was increased as demonstrated by Alcian blue-periodic-acid Schiff staining. Furthermore, acid sulfated mucin was demonstrated by high iron diamine-Alcian blue staining in the superficial layer of the metaplastic mucosa adjacent to the cancerous lesion and in the tumor itself. Sparse foci were also found in the surgical margins. We suggest that the increased content of acid sulfated mucin and its distribution might serve as an early indicator of malignant potential of the metaplastic gastric mucosa.