Abstract: Automated diagnostic decision support (104) in the imaging of potentially malignant lesions is distributed and streamlined to protect patient confidentiality and to lower bandwidth and transaction costs. At a client hospital site (108a, 108b), a software agent (132) monitors a database and responsively accesses an image of a lesion and ground truth that the lesion is malignant/benign (S310-S330). After computing at least one feature of the lesion based on the image (S340, S350), the software agent transmits the feature(s) and ground truth externally from the hospital, to a central diagnostic decision support server (S360, S370). When a client hospital site needs automatic diagnostic support, the lesion feature(s) of the new patient are likewise extracted and transmitted to the external server in a query message (S440). The classifier located on the server will return a diagnosis (benign/malignant) and a confidence level (S450, S460).