We have shown that neutrophils can also be polarised into an anti-tumorigenic N1 phenotype following IFNβ stimulation or into a pro-tumorigenic N2 phenotype following transforming growth factor beta stimulation.19 There is also increasing evidence in both human and murine studies that neutrophils inside the tumour are predominantly pro-tumorigenic, especially in advanced tumours.20, 21 While our current understanding of TANs and their potential role in tumour progression is in its infancy when compared to CD8+ T-cells and TAM, it is likely to develop in the very near future. This evidence concerns the gene CD8A and neoplasm.