The role of venous outflow in maintaining static urothelial drug levels after intravesical therapy is also corroborated by the blood levels of drugs in patients without BC [49,50] and by systemic absorption of radiolabeled urea, sodium and radio-iodinated albumin in accordance with the Stokesian diffusion principle [30,31] (see Figure 1). The gene discussed is ALB; the disease is breast cancer.