Magnetic Particle Imaging (MPI) is a novel, high-contrast, and quantitative imaging modality that directly detects superparamagnetic iron oxide nanoparticle (SPIO) tracers. These SPIOs have been previously used as a MRI contrast agent. However, with MRI SPIOs are limited by poor specificity and difficulty associated with quantifying the negative signal. MPI enables the direct detection of these SPIOs with both high sensitivity and positive contrast. MPI is well poised to support MRI in developing a clinically translatable cancer detection platform with SPIO. Here we demonstrate in vivo cancer detection and dynamic perfusion imaging with MPI.