Abstract: A method of estimating a grade of a prostate cancer from zinc data associated with the prostate, the zinc data being arranged gridwise in a plurality of picture-elements representing a zinc map of the prostate. The method comprises, clustering the zinc map according to zinc levels associated with the picture-elements, and estimating a cancer grade of at least one tissue region, based, at least in part, on zinc levels associated with a cluster of picture-elements representing the tissue region.

Abstract: Apparatus for non-invasive in vivo detection of a chemical element in the prostate of a subject, comprising: (a) a probe adapted for being inserted into at least one of the rectum or the urethra of the subject; (b) an irradiation system capable of exciting the chemical element to emit radiation to form emitted radiation; (c) a radiation detector located within the probe, wherein the radiation detector is capable of detecting the emitted radiation and wherein the radiation detector is suitable for mapping the emitted radiation; and (d) a signal recording, processing and displaying system for mapping the level of tie chemical element in the prostate of the subject at a plurality of different points in the prostate according to the mapping of the emitted radiation. In one embodiment, the irradiation system is capable of delivering exciting radiation through the probe to the prostate; in another embodiment the emitted radiation comprises fluorescent X-ray radiation.