A117: Quality Assurance (QA) of Radiotherapy Planning: Optimising the Peer Review process in a Canadian Cancer Centre

Joanna Mackenzie1,Gillian Graham1,Ivo Olivotto1

1Tom Baker Cancer Centre, Calgary,Alberta, Canada

Presenting date: Monday 2 November
Presenting time: 12.20-13.10

Background

The ‘Canadian Partnership for Quality Radiotherapy’ (CPQR) Quality Assurance Guidelines1 recommend radiation oncologist (RO) peer review of radiotherapy (RT) plans prior to radiotherapy delivery or within 25% of a treatment course. The Tom Baker Cancer Centre, Calgary holds seven disease-site specific, 1-hour weekly peer review QA meetings but outcomes were not routinely documented.

Method

Outcomes of each case reviewed at (i)Breast, (ii)Head and Neck/Thyroid/Cutaneous and (iii)Lung tumour QA rounds from Jan 6 to May 5, 2015 were recorded prospectively. Each radiotherapy (RT) plan was assigned an outcome: A (no change required), B (issue to consider for future patients), or C (change required before next fraction) as previously described2. The timing of QA relative to RT start-date, whether recommendations were initiated, whether changes could have been detected at the contouring stage and a description of each ‘B’ or ‘C’ deviation were recorded.

Results

211 RT plans prescribed by 20 ROs were peer-reviewed at 43 QA meetings. 93% were curative plans and 7% palliative. A median of 4 ROs were present for each discussion. 97% of plans were reviewed before 25% of the treatment course was delivered with 72% before the RT start-date. 28% were reviewed after contouring (prior to plan development) and 72% were reviewed after plan approval. For plans reviewed post-contouring, 26% had a ‘B’ and 10% had a ‘C’ outcome.. For post-planning reviews the ‘B’ and ‘C’ rates were 12% and 9%, respectively. 88% of ‘C’ outcomes resulted in plan changes prior to further RT. Only 55% of ‘C’ deviations would have been detected at the post-contouring stage.

Conclusion

Routine peer review of RT plans improved plan quality prior to treatment delivery. Timing of peer review at the post-contouring stage would have failed to detect 45% of ‘C’ outcomes and therefore peer review after plan completion is recommended.