Purpose: Plan quality assessments have become a ubiquitous component of plan evaluation in radiotherapy. The typical methodology assesses dose-volume histogram (DVH) constraints and applies a binary pass/fail evaluation. In this work, a framework was developed to continuously accumulate plan quality data and provide additional context during plan assessment by comparing the current plan results to the past patient population.
Results: Initial development focused on external beam radiotherapy of the breast, which has well established plan constraints and a large population of treated patients. The data for 111 patients have been collected so far. Plan quality reports can now display the current plan performance overlaid on a boxplot of the past patient population. Each subsequent patient can then be added to the population database.
Conclusion: A framework for continuous accumulation of plan quality data and feedback to the planner has been implemented. Further study is needed, but this framework is expected to lead to improvements in overall plan quality for two reasons: (1) evaluation that looks beyond pass/fail DVH constraints with the context of past patients to see where a plan may improve; and (2) the objectives currently in use can be evaluated against what has been historically achievable and adjusted accordingly to improve their efficacy.