It has been discovered that human parathyroid tumor cells express high densities of folate receptors which could provide a target that may be used for localization. In certain embodiments, the disclosure relates to methods of detecting and imaging parathyroid tumors or canccrous cells in tissues using a folatc conjugate to enhance imaging techniques such as magnetic resonance imaging, positron emission tomography, computed tomography (CT), and single-photon emission computed tomography (SPECT). An image of radioactivities or nuclear magnetic resonance frequencies as a function of location for parcels (voxels), may be constructed and plotted. The image shows the tissues in which the tracer has become concentrated.
