Patient and treatment factors associated with adverse quality of life 2 years following radiotherapy – results from the REQUITE breast cancer patient cohort
Session type: E-poster/poster
The 10-year survival rate for breast cancer is now approaching 80 %. Previous qualitative research has shown that breast cancer survivors regard long-term quality of life (QoL) as an increasingly important outcome. This study assessed the relationship between QoL, patient demographic and treatment variables 2 years following radiotherapy.
Breast cancer patients (n=2,059) were recruited prospectively following breast-conserving surgery across eight centres in the UK, Europe and North America into the multicentre REQUITE cohort study (www.requite.eu) between 2014 and 2016. Longitudinal patient reported outcomes (PROs, EORTC-QLQ-C30 and –B23) were available for 1,561 patients at baseline, following radiotherapy, and at 2-year follow-up. Patient demographic and treatment predictors of health-related QoL across the six domains of Global Health Status, Fatigue, Pain, Body Image, Arm Symptoms and Breast Symptoms were identified using multivariable linear mixed effects models.
Clinician-reported toxicity was poorly correlated with PROs. Patient BMI was adversely associated with global health status (p=0.003), pain (p<0.001) and fatigue (p=0.01). Smoking negatively affected all QoL domains (p-values between 0.003 and <0.001). Depression at baseline was adversely associated with global health status, pain and fatigue (all p<0.001). Analgesic use negatively affected all QoL domains (p=0.004 to <0.001). Non-European ethnicity was associated with increased fatigue (p=0.007) and arm symptoms (p<0.001).
Prior chemotherapy adversely affected fatigue (p=0.007) and body image (p<0.001), but reduced breast symptoms (beta -4.15, CI -3.12 to -5.18, p<0.001). Post-operative complications (haematoseroma or infection) negatively affected breast symptoms (p<0.001). Hypo-fractionated radiotherapy was associated with reduced pain, fatigue and breast symptoms (all p<0.001), whereas use of boost adversely affected global health status (p=0.002), fatigue (p=0.003) and breast symptoms (p<0.001).
BMI, smoking status, depression, analgesic use at baseline and non-European ethnicity but not other co-morbidities were associated with adverse outcomes across multiple QoL domains. Hypo-fractionation and boost use strongly affected general QoL and local symptom scales independent of radiotherapy technique. The effect for chemotherapy was mixed and other co-treatments did not affect PROs in this patient cohort.
The findings of this study help to identify patient and treatment characteristics associated with adverse long-term QoL following breast radiotherapy and should be addressed independently of factors affecting clinician-reported toxicity.