Project Summary TRD 1: Imaging Cancer Heterogeneity Precision medicine is a paradigm shift whereby personalized treatment approaches are based on knowledge of an individual’s genotype and phenotype. While it is important to match the therapeutic agents to the genetic makeup of a tumor, new strategies are needed to detect and optimally characterize the imaging phenotype of tumors and definitively determine the tumor/no tumor borders to optimize patient-specific treatments. As such, the role of imaging in assessing tumor heterogeneity and accurately characterizing those who will require definitive therapy is critical. Using image guidance for precise mapping of tumor cell composition and accurate 3D mapping of brain, prostate, and gynecological tumor burden is the best approach to characterizing tumors and guiding clinical management at diagnosis. The goal of the Imaging Cancer Heterogeneity TRD is to develop and validate molecular, micro- and macroscale imaging technologies to characterize the macroscopic and microscopic environment of tumors, tumor heterogeneity and tumor volume, and improve risk assessment to guide the precise treatment of cancer. While the initial studies will focus on brain, prostate, and gynecological neoplasms, we envision the technology and findings derived from this TRD will be broadly applicable to a variety of cancers. Hence, the aims are designed to provide novel and detailed mapping of tumor heterogeneity and define tumor borders using mass spectrometry imaging (MSI) correlated with histopathology and multiparametric MRI technologies.