Neutrophil interaction with tumour cells in small early gastric cancer: ultrastructural observations

The authors studied the neutrophil inflammatory reaction by light and electron microscopy in 4 small early gastric cancers (three tubular adenocarcinomas and one adenocarcinoma with signet-ring cell component), selected for the absence of coagulative necrosis and ulceration. Neutrophils showed ultrastructural signs of activation such as aggregation, adhesion and lipid bodies. Some neutrophils were found to be in intimate contact with the intact tumour cells and with those that displayed a varying degree of damage. In particular, relatively early damage, such as disorganization of the intermediate filaments and dilatation of the rough endoplasmic reticulum, occurred at the contact regions. In spite of the severe damage to the tumour cells, the neutrophils themselves were intact. These findings are discussed in relationship to a number of recent studies of the neutrophil-mediated tumour cell injury, in man and animals.