Immune checkpoint inhibitors (ICIs) can cause immune-related adverse events (IrAEs) throughout and beyond treatment duration. These IrAEs can be varied and difficult to predict, as they can involve almost any organ, regardless of where the primary tumor is located. Treatment modality and individual characteristics appear to influence the frequency and severity of these events, which can become serious without proper monitoring and timely intervention.

Generally, patient visits are scheduled at the same intervals in which patients receive treatment, once every two to four weeks. In these large intervals, patients can be surprised by IrAEs without a close schedule visit to their oncology physician. Not only this may negatively influence their overall well-being, their perceived self-efficacy to manage their own condition and their health-related quality of life may be affected as well.

Using patient-reported outcomes (PROs) to monitor patient symptoms has become incredibly valuable in describing treatment toxicity, including that of ICIs. PROs are a self-report of the patient's own perceptions of their health status. Using their own words, or by replying to questionnaires, patients can convey symptoms and how these affect their daily life and quality of life.

Questionnaires are an example of a PRO measure (PROM), which have increasingly been provided electronically (resulting in electronic PROs or ePROs). The ubiquity of connected electronic devices has enabled long-distance monitoring of symptoms through electronic questionnaires. In patients treated with chemotherapy, studies have shown that using this method to collect symptom data can enable healthcare providers to help patients manage their symptoms remotely. This allows patients to receive timely support from home, that could help prevent serious complications that could entail visits to the emergency department, unscheduled hospitalizations and treatment interruptions.

The IePRO study's aim is to test a model of care that uses electronic questionnaires to monitor symptoms that could be related to the use of ICIs. Patients would reply to these questionnaires at least once a week using an electronic web application (on their phone or computer). A team of oncology nurses reviews their replies and calls patients when new symptoms appear or when they worsen. Using a standard triage algorithm, the nurses guide patients on how to proceed: if they should stay home and follow self-care advice, if they should have a second call within the next 24 hours to follow-up on their symptoms, or if they should come to the hospital for an in-person assessment as soon as possible.

In this study, it is hypothesized that this model of care could lead to an earlier detection of IrAEs, as well as their improved management by reducing the number of high-severity IrAEs, the number of unscheduled emergency admissions and hospitalizations, as well as decreasing the number of treatment interruptions and of immunosuppressive treatments used to treat IrAEs.

Inclusion Criteria:

• Patients 18 years old or older
• Patients diagnosed with cancer
• Patients starting or re-starting systemic ICI therapy treatments (adjuvant, neo-adjuvant, metastatic)
• Informed Consent as documented by signature

Exclusion Criteria:

• Patients that self-declare not being able to use an ePRO application and complete a questionnaire in French.
• Patients with any psychological, familial or sociological condition and linguistic limitation potentially hampering compliance with the study protocol requirements and/or follow-up procedures. These conditions will be discussed between the recruiting oncologist and the patient before trial entry.
• Patients that are re-starting ICI therapy, but that have previously participated in this intervention.
• Patients with a cognitive impairment, as declared in the patient record
• Patients participating in other interventional clinical studies.