Fig. 11.

Base case with vessel shutdown. Simulation of vascularized tumor growth with one viable cell species. Stability of the tumor morphology and its invasiveness are directly linked to the availability of cell substrates regulated by the dynamically evolving vasculature. At time t = 23, the supply of cell substrates is shut off by the collapse of vessels due to increasing pressure from the surrounding proliferating cells. The tumor mass then undergoes temporary regression (t = 25). By t = 29, neovascularization is apparent in response to the increased hypoxia in the interior of the tumor. Viable tumor tissue (blue color) is shown in 3-D contours representing density values of 0.1, 0.2, and 0.6 (min.: 0.0; max.: 1.0); complete absence of viable tissue is shown in gray. Conducting vessels: brown; non-conducting: white. Time unit = 1 day. (Grid length = 200 µm).