Five-year trends and baseline predictors of patient-reported adverse events following breast radiotherapy with a boost in the IMPORT HIGH phase III randomised controlled trial.

Abstract

IMPORT HIGH demonstrated non-inferiority of simultaneous integrated boost against sequential boost for ipsilateral breast tumour relapse. Patient-reported adverse events (AEs) were similar across treatment groups. In this longitudinal analysis of patient-reported AE data from IMPORT HIGH we describe prevalence and baseline predictors of patient-reported AEs over 5-years. IMPORT HIGH (ISRCTN47437448) recruited women with early breast cancer and higher-than-average local recurrence risk. All participants received breast radiotherapy and a boost. Patient-reported outcomes (PROs) were recorded using EORTC QLQ-C30, QLQ-BR23, Body Image Scale administered at baseline, 6 months, 1, 3, 5-years. AEs were recorded on a 4-point-scale and dichotomised (none/mild versus moderate/marked) for analysis. Generalised Estimating Equations assessed patterns of moderate/marked AEs and their baseline predictors. 52/76 IMPORT HIGH centres participated in the PRO sub-study. 1078/1338 patients consented. 270/762 (35.4 %) patients reported no moderate/marked AEs at 5-years. Most common moderate/marked AEs at 5-years were overall change in breast appearance (257/762, 33.7 %) and having a smaller breast (222/762, 29.1 %). Arm and breast symptoms peaked at 6-month assessment, with breast symptoms improving but arm symptoms persisting over 5-years. Body image-related AEs improved from baseline. Younger age and anxiety were the commonest baseline predictors of AEs. This longitudinal analysis of PROs in a large trial of breast and boost radiotherapy demonstrates an overall decrease in the number of patient-reported moderate/marked AEs up to 5-years following radiotherapy. Baseline factors predicting AE development include younger age and anxiety, informing support strategies for patients receiving whole breast and boost radiotherapy.