Anomaly Detection in Time Series Radiotherapy Treatment Data

Abstract

The work presented here resulted in a valuable innovative technology tool for automatic detection of catastrophic errors in cancer radiotherapy, adding an important safeguard for patient safety. We designed a tool for Dynamic Modeling and Prediction of Radiotherapy Treatment Deviations from Intended Plans (Smart Tool) to automatically detect and highlight potential errors in a radiotherapy treatment plan, based on the data from several thousand prostate cancer treatments at Moore Cancer Research Center at University of California San Diego. Smart Tool determines if the treatment parameters are valid, against a previously built Predictive Model of a Medical Error (PMME). Smart Tool has the following main features: 1) It communicates with a radiotherapy treatment management system, checking all the treatment parameters in the background prior to execution, and after the human expert QA is completed, 2) The anomalous treatment parameters, if any, are detected using an innovative intelligent algorithm in a completely automatic and unsupervised manner, 3) It is a self-learning and constantly evolving system, the model is dynamically updated with the new treatment data, 4) It incorporates expert knowledge through the feedback loop of the dynamic process which updates the model with any new false positives (FP) and false negatives (FN), 4) When an outlier treatment parameter is detected, Smart Tool works by preventing the plan execution and highlighting the parameter for human intervention, 5) It is aimed at catastrophic errors, not small errors.