Granulocyte colony-stimulating factor (G-CSF): a novel anticancer therapy based on the "universal dynamics of tumor growth"?

It has recently been proposed that all solid tumors exhibit the same growth dynamics. This hypothesis, developed by Bru and coworkers and called the universal dynamics of tumor growth, says that the main mechanism responsible for tumor progression is cell diffusion on the tumor border. The authors of this hypothesis claim that, by inducing strong neutrophilia around the tumor, this dynamic can be changed; neutrophils would locate themselves to eliminate cell diffusion on the tumor border therefore inhibiting tumor growth. The authors suggest that this approach may be exploited to develop effective anticancer strategies, and they have recently reported the possible cure of a 56-year-old patient with advanced hepatocarcinoma treated with granulocyte colony-stimulating factor (G-CSF), a key regulator of neutrophil production. The present report shows evidence that suggests that it is very unlikely that neutrophil-induced cancer cell death is mediated by a mechanical impediment at the tumor border. Furthermore, it is shown that the induction of neutrophilia is not a new anticancer strategy based on the "universal dynamics of tumor growth", but a known approach that has been widely explored along the years. The merits of G-CSF for being tested in clinical trials with cancer patients are finally evaluated.