Dynamics of tumour cords following changes in oxygen availability: A model including a delayed exit from quiescence

In this paper, we investigate the formation of tumour cords (cylindrical arrangements of tumour cells around blood vessels) within a tumour tissue. The shrinkage and the expansion of the cord following a stepwise decrease or, respectively, increase of oxygen tension in the blood vessel are also described. The model represents the tumour cell population as a continuum and includes two novel aspects with respect to our previous works: cell death does not occur instantaneously, but is preceded by a reversible prenecrotic state; the recruitment of cells from quiescence into proliferation may require a recovery period. Model predictions are compared with experimental data reported by Hirst et al..