1. A diagnostic image processing system comprising: a user interface with which a user selects a region of interest of at least one baseline diagnostic image of a current patient having a current patient identity from which parameter values are to be extracted; a subject database that stores diagnostic images generated at different times each in association with at least a patient identity and a date, the subject database being updated each time a patient is imaged; a database searching means that searches the subject database with the current patient identity for the stored diagnostic images containing the selected region of interest of the current patient; a parameter extraction processor that extracts the parameter values from the selected region of interest of the at least one baseline image of the current patient and extracts like parameter values from the selected region of interest of the stored diagnostic images of the current patient or from data for generating the stored diagnostic images of the current patient; and, a report formatting means for formatting the extracted parameter values from the at least one baseline image and the stored diagnostic images of the current patient generated at different times into a report descriptive of the parameter value's development with time.