TARGIT-A compared single-dose intra-operative radiotherapy (IORT) to 6-7 weeks of daily conventional external beam radiotherapy (EBRT) in women with early breast cancer. IORT was found to have non-inferior risk of local cancer recurrence and survival. The preferred treatment approach is IORT during WLE. IORT as a separate procedure still offers convenience but may come at a higher risk of local recurrence. Investigation of patient treatment preferences can identify what risk of recurrence patients would be willing to accept to have IORT, and in what setting.
Treatment preferences were determined by self-rated questionnaires using validated trade-off methodology in two cross-sectional studies: a) 209 TARGIT-A participants (IORT group n=108, EBRT group n=101); b) 123 similar patients diagnosed with breast cancer yet to receive radiotherapy (Pre-Treatment group), 85 of whom also submitted post-radiotherapy questionnaires.
The only significant factor driving treatment preferences for TARGIT-A patients was the treatment they had received as part of the trial, such that 60% of IORT patients would accept IORT at an increased risk of 4%-6% in contrast to 12% of patients in the EBRT group.
85% of the pre-treatment group reported IORT an acceptable treatment option, with 23% indicating increases of 4-6% would be acceptable in the trade-off for convenience. If all treatment modalities offered equivalent outcomes, 13% of patients chose EBRT, 25% chose IORT as separate procedure and 62% chose IORT during WLE as their preferred option. These results differed in the post-treatment questionnaire such that there was more acceptance of IORT in the pre-treatment stage.
Breast cancer patients yet to receive radiotherapy are willing to accept a more convenient treatment option even at a greater risk of recurrence. Measured patient preferences are highly influenced by experience of treatment received. Post-treatment preference studies may not reflect views of women who need to make treatment decisions.