Although tumor necrosis may be associated with mild to moderate leukocytosis, another explanation for a rise in WBC count (particularly when “leukemoid” like) in patients with cancer may be related to granulocyte colony-stimulating factor (G-CSF) production by the neoplasm itself.
In vivo production of G-CSF by bladder cancer was reported over 25 years ago in a patient with marked leukocytosis (>100,000)1. Subsequently, numerous G-CSF-producing tumors have been reported, including those associated with the genitourinary tract (eg, bladder, ureter, prostate), lung, gynecological organs, gallbladder, stomach, esophagus, small intestine, pancreas, mesothelioma, thyroid, and myeloma2.
In most cases, G-CSF-producing tumors are advanced with very poor prognosis 2. Although the mechanism underlying a link between G-CSF production and tumor progression is unclear, a direct action on GCSF receptors of tumor cells, formation of more aggressive cancer cells, and changes in the function of T-cells and endothelial cells that may enhance tumor growth have been postulated2.
- Ito N, Matsuda T, Kakehi Y, et al. Bladder cancer producing granulocyte colony-stimulating factor. N Engl J Med 1990;323:1709-10.
- Yamano T, Moril E, Ikeda J-I, Aozasa K. Granulocyte colony-stimulating factor production and rapid progression of gastric cancer after histological change in the tumor. Jpn J Clin Oncol 2007;37:793-796.