Gastritis cystica polyposa associated with a gastric stump carcinoma, with special reference to cell kinetics and p53 gene aberrations

We report a case of gastritis cystica polyposa (GCP) that developed in association with a small stump carcinoma. The patient had had distal gastrectomy for peptic ulcer 33 years prior to the present illness. Total gastrectomy was carried out for the stump carcinoma of the remnant stomach, followed by Roux-en-Y anastomosis. Histological examination revealed that the cancer was associated with a GCP lesion in its neighborhood. The resected stomach was subjected to a cell kinetics study and p53 gene analysis, as GCPs are thought to have a high potential for carcinogenesis. The GCP mucosae, as well cancer tissues and remnant mucosae obtained from the same specimens, were investigated and compared. We found that cell kinetics, as measured by a Ki-67 labeling index count, was more accelerated in the GCP than in the remnant mucosa, and that p53 gene aberrations, including both mutations and deletions, took place in the GCP lesion. As the p53 gene is considered to be recessive, in principle, its tumor suppressive activity is lost only when gene aberration, either mutation or deletion, occurs concurrently or successively in both alleles. It was of interest to us that a benign lesion such as GCP had, in this instance, already developed both gene aberrations, strongly suggesting a precancerous nature for this disease.