Selecting Immune Checkpoint Inhibitor Side Effects for Real-Time Monitoring in Routine Cancer Care: A Modified Delphi Study

PURPOSE Electronic patient-reported outcome (ePRO) symptom monitoring may support the safe delivery of immune checkpoint inhibitors (ICI). There is no consensus on which side effects should be monitored in routine care. We aimed to develop a prioritized list of ICI side effects to include in ePRO systems and compare this to existing ICI-specific patient-reported outcome measures (PROMs). METHODS We conducted a two-round modified Delphi survey. Participants were patients (or their carers) who had received/were receiving ICI or managing health care professionals (HCPs). Round 1 (R1) side effects were generated from a literature review and existing PROMs. In R1, participants rated the importance of 63 ICI side effects in an ePRO system on a five-point Likert scale. In round 2 (R2), participants ranked the 10 most important side effects from 36 side effects. Content mapping of the prioritized list against existing PROMs was conducted. RESULTS In R1, 47 patients, nine carers, and 58 HCPs responded. Twenty-eight side effects were rated important (I)/very important (VI) by >75% of participants and included in R2. Ten were rated I/VI by <50% of participants and excluded. Twenty-five were rated I/VI by 50%-75% of participants and discussed at an HCP roundtable to determine inclusion in R2. In R2, 39 patients, 11 carers, and 42 HCPs ranked seizures, shortness of breath, chest pain, diarrhea, and rash as the most important side effects for monitoring. Content mapping showed significant differences between the prioritized list and existing PROMs. CONCLUSION We developed a consumer- and clinician-driven prioritized list of 36 ICI side effects to include in future ePRO systems. This process highlights the importance of broad stakeholder engagement in side-effect selection and rigorously identifying clinically important side effects to ensure content validity and clinical utility.