Abstract

Mesenchymal tumours other than gastrointestinal stromal tumours are rare in the stomach. Nevertheless it is important to incorporate them into the differential diagnosis. Plexiform angiomyxoid myofibroblastic tumour is a recently described new entity of a presumably benign mesenchymal gastric tumour. This report presents what is believed to be the third case of this tumour. The tumour is characterised by bland spindle cells in a plexiform pattern, a mucinous extracellular matrix and a network of thin blood vessels. These findings are completely in line with the two previous reported cases. There was a strong positivity for α-smooth muscle actin and a low proliferation index (<2%). The tumour had no C-KIT or CD34 expression and no mutation in the C-KIT and PDFGRα genes. Plexiform angiomyxoid myofibroblastic tumour may present a new mesenchymal tumour entity in the stomach.