A number of factors have been instrumental in shaping contemporary thoracic radiologic practice. First, thoracic imaging data is increasingly digital in nature, which has made quantitative image analysis a practical goal. Secondly, thoracic radiology consultation within the multidisciplinary setting of oncology demands that increasing amounts of data be abstracted, indexed, linked, and efficiently communicated within a distributed environment. Although some of the analytical and information management tools required to support these needs exist, it is within the electronic infrastructure of PACS that they become practical and clinically accessible. We propose to expand the capabilities of PACS beyond its historical role to enhance the research and clinical needs of thoracic imaging by providing: (1) image analysis tools to extract quantitative information from image data pertaining to respiratory function as well as tumor volumes; and (2) PACS-based information processing tools to integrate all of the multimedia data relevant to the management of cancer patients. This will be accomplished by developing PACS-based analytical software to address specific physiologic questions in patients with airflow obstruction as well as knowledge-based methods for the measure of tumor and lung volumes. In addition, an Oncology Imaging Time Line will be developed for lung cancer patients that indexes diagnostically relevant image data with textual and numerical data from other databases in the electronic medical record. Using advanced data integration software and automated free text analysis routines, a multimedia summary will be generated by which the progress of cancer patients can be efficiently tracked. Addressing these PACS applications will stimulate advances in the very fabric of contemporary PACS technology, ranging from network strategies to workstation design to sophisticated data management.