Patient-reported outcomes and experiences from a prospective cohort study of older patients with cancer on checkpoint inhibitors: The ELDERS study

Introduction: Checkpoint inhibitors (CPI) are widely used across different tumour types in older cancer patients. The ELDERS study investigated primarily the safety of CPI in older patients, and secondarily its impact on health-related quality of life (HRQoL), comparing older and younger patients. Here we describe the results from its secondary aim. Materials and Methods: This was an observational, mixed methods study, consisting of questionnaires and qualitative interviews. Patients completed the EORTC QLQ-C30 at baseline and at three-monthly reviews (up to four over the planned 12 months on study). Results: One hundred and forty patients, 70 in each age cohort (older: ≥70 years of age, younger: <70 years of age), were recruited. Twenty-four patients, 12 in each age cohort, were interviewed. The mean baseline EORTC QLQ-C30 score was 65/100 for both cohorts combined, and the score for the full QLQ-C30 assessment was 78/100 and 75/100 for older and younger, respectively. The physical functioning score was the only subscale to change significantly between baseline and the first and second reviews (p = 0.03 and 0.04, respectively), resulting from some improvement in the mean score (from baseline) within the younger cohort and some decline within the older cohort. However, when focusing on each cohort separately, the change over time was not statistically significant for either. Two main themes from the interviews were ‘expectations’ (thoughts about treatment before commencing) and ‘experience’ (lived experience during treatment). Discussion: Quantitatively, there was no difference in the effect of CPIs on HRQoL between the cohorts, although qualitative data from interviews suggested that there were some experiential differences. People in the older cohort were less likely to seek additional information about CPIs and were more likely to report side effects. In terms of both ‘expectations’ and ‘experience,’ the older cohort was a heterogenous group, highlighting that an individualised approach is needed when supporting this group. This study shows that older patients can be reassured that immunotherapy is unlikely to negatively impact their HRQoL more than younger patients, and it should be considered a viable treatment option.