“…The production of granulocyte colony‐stimulating factor (G‐CSF) or granulocyte macrophage colony‐stimulating factor (GM‐CSF) by the tumor itself is thought to be responsible for this paraneoplastc syndrome 1, 2, 3. Varieties of nonhematopoietic malignant tumors, including bladder carcinoma,4, 5, 6 hepatoma,7 mesothelioma,8 squamous cell carcinoma of the oropharynx,9 melanoma,10 glioblastoma,11 sarcoma12,13 and carcinoma of the lung14, 15, 16, 17, 18 have been demonstrated to secrete G‐CSF or GM‐CSF in an amount large enough to cause a significant systemic hematopoietic effect. Several reports also have demonstrated the presence of an autocrine growth loop for G‐CSF and GM‐CSF in nonhematopoietic tumor cells 19, 20, 21.…”