When the tumor volume reaches above 2 mm3, diffusion limitation sets in, which eventually impairs nutrition intake, waste excretion, and oxygen delivery.5 Such rapidly growing cancer cells recruit the generation of new blood vessels, a phenomenon called angiogenesis (or neovascularization). Aberrant tortuosity, abnormalities in the basement membrane, and the lack of pericytes lining endothelial cells are the features of this process, which results in leaky vessels with gap sizes of 100 nm to 2 μm, depending upon the tumor type.7 Moreover, such tumors exhibit poor lymphatic drainage due to the high interstitial pressure at the core of the tumor than at the periphery. This combination of leaky vasculature and poor lymphatic flow results in enhanced permeation and retention (EPR) effect. NPs can preferentially localize in cancerous tissues owing to their size being smaller than blood vessel fenestration and be entrapped in the tumor due to higher retention ability than the normal tissues.