Interstitial flow is the convective transport of fluid through tissue extracellular matrix. This creeping fluid flow has been shown to be important in regulating the development, function, and pathology of tissues. Furthermore, interstitial flow has been shown to affect the morphology and migration of cells such as fibroblasts, cancer cells, endothelial cells, and mesenchymal stem cells (1). Chary and Jain used fluorescence recovery after photobleaching to directly observe fluid flow in the tissue interstitium and determined typical flow velocities are on the order of 0.1–2.0μm/s (2). Interstitial flow is particularly important in driving transport in tumor tissues, as neoplastic tissue is often characterized by increased interstitial pressure (3).