Expert systems for efficient handling of medical information. I. Lung cancer

Rule-based expert systems offer the ability to quickly retrieve considerable amounts of information relevant to specific situations; the technology can be potentially very useful to physicians in an era characterized by an explosion of medical data. A simple rule-based expert system that allows a microcomputer user to obtain staging, prognostic and therapeutic information relevant to patients with lung cancer is presented. The program was constructed by utilizing an inexpensive expert system development package (EXSYS). Using information from the literature, 194 rules were formulated; these rules can be expanded or updated at any time. The computer user interacting with the system is asked sequential questions regarding the characteristics of the tumor (T) of a particular patient, the nodal status (N), the presence or absence of metastasis (M), how the staging information was derived (clinically or at surgery), the tumor cell type and the therapeutic options being considered (different surgical procedures, radiotherapy, chemotherapy and others). The system selects the appropriate answers and displays the stage of the tumor and relevant prognostic information. The microcomputer user can also examine the rules that were selected by the system. These rules have relevant comments that apply to the specific condition, as well as appropriate references. The microcomputer user can change all or some of the conditions (i.e., therapeutic options) and compare the results of the various "WHAT-IF" simulations.