[Gastric collision tumor with osseous metaplasia]

Abstract

Neuroendocrine cells are frequently found in gastric tumours, although they rarely make up more than one third of the total number of tumour cells. When juxtapositioning of the two kinds of tumour cells occurs a "collision tumour" is formed. These have been described to occur with varying frequency throughout the digestive tract. They are uncommon in the stomach. We describe a case, of a gastric collision tumour in which an adenocarcinoma coexisted with a carcinoide tumour and there were zones of bony metaplasia in the transition area between the two tumors. Positive CEA, VIP, beta-HCG and TSH on inmunohistochemical analysis was found.