Possible paracrine growth of adenocarcinoma of the stomach induced by granulocyte colony stimulating factor produced by squamous cell carcinoma of the oesophagus

Synchronous cancers of the oesophagus and stomach diagnosed in a patient showing pronounced leucocytosis were examined for production of granulocyte colony stimulating factor (G-CSF) and expression of G-CSF receptor. Whereas enzyme immunoassay of tissue extracts showed that the oesophageal carcinoma produced G-CSF, the gastric cancer did not. However, the gastric tumour showed G-CSF receptor expression on immunohistochemical examination of sections. These findings suggest that the oesophageal cancer promoted gastric cancer growth by paracrine mechanisms involving G-CSF.