Bladder carcinoma producing granulocyte colony-stimulating factor: a case report.

A 67-year-old man with squamous cell bladder carcinoma showed remarkable leukocytosis (maximum 50,300 per microliter.) for 4 months while the neoplasm recurred and metastasis progressed. The patient died of systemic metastasis within 9 months after cystectomy. Enzyme immunoassay of the serum demonstrated remarkably high levels of granulocyte colony-stimulating factor (4,928 pg./ml.). Immunohistochemical examination with anti-granulocyte colony-stimulating factor monoclonal antibody demonstrated granulocyte colony-stimulating factor production in the metastatic cancer cells in the liver. The expression of the granulocyte colony-stimulating factor gene in the tumor specimens was examined by standard Northern blot analysis. Specific granulocyte colony-stimulating factor transcript was identified in the total ribonucleic acid fraction extracted from a tumor specimen of the peritoneal metastatic lesion. These results indicated that the autonomous production of granulocyte colony-stimulating factor in this bladder carcinoma induced paraneoplastic leukocytosis.