Identification of the PROMs used to assess ICI toxicities and HRQoL in patients receiving immune checkpoint inhibitor treatment in cancer care and their suitability: A systematic review

Background: The implementation of patient-reported outcome measures (PROMs) in the clinical identification of immunotherapy toxicities is a complex intervention. There has been very little work evaluating the clinical utility and generalisability of PROMs used after immune checkpoint inhibitor (ICI) treatment to date. We reviewed evidence on the use of PROMs assessing toxicities and health-related quality of life in patients treated with ICIs. Methods: PubMed, EMBASE, MEDLINE, PsycInfo, CINAHL, Web of Knowledge, the Cochrane Library were searched (January 2008 - October 2024). Quantitative studies reporting the use of PROMs to identify, assess and manage toxicities at any timepoint and HRQoL associated with ICI treatment in adult patients with cancer were included. A narrative synthesis describes the key characteristics of the PROMs identified. Results: 43 studies were included; 12 on melanoma/skin, 12 on lung and 19 on other cancers. Study designs included 20 randomised controlled trials, 14 cohort studies, six cross-sectional studies and three non-randomised interventional trials. The lack of ICI-specific PROMs was highlighted, particularly as the PROMs used lacked sufficient sensitivity for ICI treatments. Conclusions: There is need for an ICI-specific PROM for effective assessment of toxicities and a tailored PROM for assessment of HRQoL. Some suggested key domains by certain studies for ICI-specific PROMs include: (a) ICI- specific items (e.g. certain USD-I and PRO-CTCAE items) to capture symptoms associated with ICI treatments such as rash, myalgia, (b) role, psychological, emotional and social functioning domains within HRQoL assessments and (c) additional patient-reported toxicities not included in existing PROMs. Findings emphasize the importance of using a disease-specific PROM that is applicable, acceptable and sufficiently sensitive to identify toxicities and HRQoL issues across all stages.