Implementation of an Automatic Contouring System within a Radiation Therapy Department

Purpose/Aim

The observable increase in advanced palliative treatment plans and retreat patients adds to planning complexity, necessitating more contours within shorter timelines to accommodate urgent cases. To support the increased demand for complex palliative treatment cases and reduce slowdowns, an automatic contouring (AC) system was installed and integrated into the planning workflow. The goal was to improve contouring completion time by having CT simulation staff review, edit and approve automatically generated contours rather than generate them manually.

Methods/Process

An initial study assessed readiness, ease of use and end product outcomes prior to selecting an AC system vendor and implementation in 2024. By utilizing a “one-click,” cloud based solution, a smooth integration was achieved requiring only a single day of vendor installation. A training program was facilitated by physics and delivered to CT simulation staff with regular, routine follow-up where changes to the workflow were discussed. These changes were developed based on feedback from Radiation Oncologists, dosimetry and physics. After completion of a planning CT-scan, the dataset is manually sent to the AC system via a DICOM export. Contours generated by the AC system are then manually reviewed and edited by CT simulation staff, prior to plan creation and publishing.

Results or Benefits/Challenges

Initial investigations proved that contour accuracy and integrity between the AC system and those generated by radiation therapists were comparable. Furthermore, qualitative feedback from CT simulation and dosimetry staff indicates an increase in productivity and workflow improvement. Over-contouring by the AC system resulted in excessive contours requiring manual deletion prior to publishing. To address this, a batch deletion tool was developed and implemented early in the system's deployment. Another challenge was the AC system's shortcomings in handling brachytherapy patients. While this issue remains unresolved, efforts are ongoing in collaboration with the vendor to improve the AC system's use for this patient population. The AC system utilizes standardized templates to apply applicable contours, initial challenges did arise with wrong templates being applied by both CT simulation staff and the Radiation Oncologist. The frequency of this arising diminished over time with routine follow-up and additional training which included further transparency in mapped contour templates.

Conclusions/Impact

Addressing the challenges early on in the implementation of the AC system allowed for overall staff acceptance. The system is now used to automatically generate contours for planning CT scans that includes all treatment sites and urgency codes. The AC system has proven most effective for advanced palliative plans (VMAT), enabling quicker turnarounds on condensed timelines, while managing the increased contouring demands. The use of the AC system is a standing item at all technical site groups to review and optimize its effectiveness for any site specific issues that may arise.