Autocrine growth by granulocyte colony-stimulating factor in malignant mesothelioma.

We report the first case of a malignant mesothelioma expressing not only granulocyte-colony stimulating factor (G-CSF), but also its receptor. A 59-year-old male carpenter underwent a panpleuropneumonectomy, but the tumor relapsed and spread rapidly, accompanied by leukocytosis. The white blood cell count reached 147,000/mm3 (96.2% neutrophils), and the concentration of serum G-CSF was 77 pg/mL. An autopsy demonstrated that some of the tumor cells produced G-CSF, but more tumor cells and endothelial cells in the tumor expressed G-CSF receptor. It was hypothesized that an autocrine loop involving G-CSF and the G-CSF receptor greatly accelerated the tumor growth.