Is There a Role for Exercise When Treating Patients with Cancer with Immune Checkpoint Inhibitors? A Scoping Review

SIMPLE SUMMARY: Immune checkpoint inhibitors (ICIs) are drugs which treat cancer by manipulating the immune system. Exercise also influences the immune system and helps to reduce symptoms in people with cancer, particularly fatigue. However, the effect of combining exercise with ICIs has not been well established. We hypothesise that the combined approach will produce beneficial outcomes for people with cancer (such as fewer side effects from ICIs and better killing of cancer cells). To determine the need for, and design of, future studies which address this hypothesis, we first need to understand what previous research has already shown. We aim to identify previous studies which have investigated this topic. Subsequently, by summarising their findings, we aim to communicate the key gaps in current understanding and provide informed recommendations about the direction, and design, of future research addressing the role of exercise during ICI treatment for people with cancer. ABSTRACT: The impact of using exercise as a non-pharmacological intervention in patients with cancer receiving immune checkpoint inhibitors (ICIs) is not well known. Our objective was to determine the extent of, and identify gaps within, available literature addressing the effect of exercise on (a) oncological outcomes and (b) quality of life (QoL) in patients with cancer receiving ICIs, and (c) the underlying biological mechanisms for such effects. We conducted searches across EMBASE, APA PsycInfo and Ovid MEDLINE(R). Studies were eligible if they addressed at least one aspect of the objective and were available in the English language. Results were synthesised using a narrative approach and subsequently discussed with multidisciplinary stakeholders. As of the final search on 5 April 2022, 11 eligible studies were identified, of which 8 were preclinical and 3 were clinical. Clinical studies only focused on QoL-related outcomes. When studies were grouped by whether they addressed oncological outcomes (n = 7), QoL (n = 5) or biological mechanisms (n = 7), they were found to be heterogeneous in methodology and findings. Additional evidence, particularly in the clinical setting, is required before robust recommendations about whether, and how, to include exercise alongside ICI treatment can be made.