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ESTRO 37

Postoperative cross-sectional analysis showed that fatigue and role functioning were significantly worse in IORT patients, but the difference was not clinically relevant (Table 1). Post-treatment cross-sectional analysis showed that role functioning was significantly ánd clinically worse for IORT. Physical functioning, pain and breast symptoms were significantly, but not clinically worse for IORT patients post-treatment. These results suggest a strong influence of surgical recovery. At 1 year none of the functioning or symptom scales were significantly different between the treatment groups. Multivariable analysis of GHS at 1 year identified comorbidity (OR -7.2; -13.2 - -1.2) and systemic treatment (hormonal and chemotherapy) (OR -13.7; -21.7 - -5.9) as significant predictors of GHS.

assessments. The IMPORT LOW trial found PROMs are capable of differentiating different radiotherapy fractionation regimens. We conducted an analysis to identify the concordance between PROMs and either clinician or photographic assessments within the IMPORT LOW trial with the aim of exploring if PROMs could be used as the primary NTE data ascertainment method in clinical trials. Material and Methods IMPORT LOW (ISRCTN12852634) is a multicentre randomised phase III non inferiority trial comparing the safety and efficacy of standard whole breast radiotherapy with two experimental schedules (reduced dose and partial breast radiotherapy). IMPORT LOW included annual clinician assessments of NTEs in all participants, and PROMs (at 6 months, 1, 2 and 5 years) and photographs (at 2 and 5 years after radiotherapy) in a planned subset of >50% patients. Weighted kappa statistic and Bowker’s test of symmetry were used to test concordance between PROMs, clinician and photographic assessments at 2 and 5 years as detailed in table 1. Analyses were conducted for the overall trial cohort as well as stratified according to baseline patient characteristics including age, treatment group, breast size and surgical deficit assessed on baseline photographs, HADS anxiety and depression subscales, body image scale, whether the patient lives alone, and education level.

Results 2016 patients were recruited to the IMPORT LOW trial. 1265 and 1319 patients consented to the PROMs and photographic sub-studies respectively. PROMs were available at 2 years for 1040 patients of whom 918 had clinician and 736 had photographic assessments. At 5 years PROMs were available for 962 patients of whom 817 had clinician and 583 patients had photographic assessments. Patients reported more NTEs than clinicians or via photographs (p<0.001 for most NTEs). Concordance was generally poor on an individual patient level; weighted kappa ranged from 0.03 (overall change in appearance) to 0.17 (breast shrinkage). % agreement was lowest between PROMs and photographic assessments for change in breast appearance (26.4%) and highest between PROMs and clinician assessment for breast oedema (90.6%). Concordance was not affected by the baseline characteristics tested and was similar between data ascertainment methods at 2 and 5 years. Conclusion Concordance was poor on an individual patient level however there was agreement on a population level as both PROMs and clinician assessments were able to distinguish between the radiotherapy schedules in IMPORT LOW. Poor concordance on an individual patient level may result from the data ascertainment methods having different comparators and patients reporting more NTEs. PROMs should be prioritised and further exploration of PROMs as a primary data ascertainment method is required.

Conclusion EB-APBI and IORT were well tolerated. HRQL temporarily decreased after treatment, but recovered within 3 months, resulting in no clinically relevant differences compared to baseline 1 year after treatment in both groups. Differences in symptom scales after treatment can be contributed to the surgical impact after IORT. At 1 year, systemic therapy and comorbidity have significant impact on GHS. OC-0156 Concordance of patient reported outcomes with clinician and photographic assessments in IMPORT LOW I.S. Bhattacharya 1 , J.S. Haviland 1 , A.M. Kirby 2 , P. Hopwood 1 , J.R. Yarnold 3 , J.M. Bliss 1 , C.E. Coles 4 1 Institute of Cancer Research, Clinical Trials and Statistics Unit, London, United Kingdom 2 Royal Marsden Hospital, Department of Radiotherapy and Imaging, London, United Kingdom 3 Institute of Cancer Research, Department of Radiotherapy and Imaging, London, United Kingdom 4 University of Cambridge, Department of Oncology, Cambridge, United Kingdom Purpose or Objective Normal tissue effects (NTEs) from breast radiotherapy are variously assessed using patient reported outcome measures (PROMs), clinician and/ or photographic