The enzyme histochemistry of gastric carcinoma in man

The histoenzymatic activity of numerous hydrolytic and oxidative enzymes was determined in cryostat sections of fresh tissues obtained surgically from 15 patients with gastric carcinoma, 18 normal subjects, and 28 patients with chronic atrophic gastritis and intestinal metaplasia. The average enzyme activity in malignant cells was less than that found in intestinal metaplasia but greater than that found in normal gastric surface epithelium. Stromal inflammatory cells exhibited activity for acid phosphatase and B-glucuronidase, and smooth muscle fibers stained for the lactic and succinic dehydrogenases and DPN and TPN diaphorases. These elements and the islands of intestinal metaplasia found in malignancy-bearing stomachs may contribute to the elevated levels of certain enzymes found biochemically in gastric secretions and tissue homogenates from patients with gastric carcinoma. Lactic dehydrogenase and the diaphorases were found in many carcinomata whereas succinic dehydrogenase was found in only one case. This pattern may be related to the high glycolytic rate characteristic of most malignant tumors, including those arising in the stomach.