A general theoretical framework for transvascular exchange and extravascular transport of
fluid and macromolecules in tumors is developed. The resulting equations are applied to the
most simple case of a homogeneous, alymphatic tumor, with no extravascular binding.
Numerical simulations show that in a uniformly perfused tumor the elevated interstitial
pressure is a major cause for heterogeneous distribution of nonbinding macromolecules,
because it (i) reduces the driving force for extravasation of fluid and macromolecules in …