We have previously measured the global uptake of blood-borne albumin, and found that it was strongly correlated to the extracellular volume fraction of the tumour tissue (Graff et al, 2000) and was not limited by the permeability of the microvascular wall (Bjørnæs and Rofstad, 2001; Graff et al, 2001). The gene discussed is ALB; the disease is neoplasm.