Rationale: Tremendous anti-tumor effects have been achieved using immune checkpoint inhibitors for melanoma and NSCLC with long lasting responses of more than 2 years in a substantial subgroup of patients. However, we are still largely unaware of the health-related quality of life of these patients. We should carefully and thoroughly assess the long-term burden of disease and treatment toxicity.

Objective: Primary Objective: to investigate health-related quality of life (HRQoL) of patients surviving 2 years or more after the first cycle of an immune checkpoint inhibitor for melanoma or NSCLC. Secondary Objectives: to assess neurocognitive function, endocrine function, cardiovascular risk, physical fitness, mood disorders, sexual problems, work participation in patients surviving 2 years or more after the first cycle of immune checkpoint inhibitor; to assess quality of life of the caregivers of these patients.

Study design: Observational cross-sectional study. Study population: Patients (age ≥18 years) with melanoma or NSCLC ≥2 years since treatment with at least one cycle of immune checkpoint inhibitor (CTLA-4 inhibitor, PD-(L)1 inhibitor, or both).

Main study parameters/endpoints: health-related quality of life (HRQoL) as measured using the EORTC Quality of life questionnaire (QLQ-C30). Secondary study parameters: possible late effects (neurocognitive dysfunction, endocrine disorders, dermatologic complaints, sexual disorders and infertility, increased cardiovascular risk, and fatigue), physical fitness, psychosocial issues related to work/education, mood disorders (anxiety and depression), patient and treatment-related factors potentially influencing development of late effects, well-being, and quality of life of caregivers.

Participation in the study will include one study visit of approximately 2.5 hours. If possible, the study visit will be combined with a regular follow-up visit. Vena puncture is the only invasive procedure, with low risk of adverse effects. Blood will be drawn after an overnight fast. To minimize the duration of the visit, patients will be offered to fill out the questionnaires at home. Individual adverse test results will be reported to a participants' treating physician to enable treatment or follow-up as indicated. The results of the full study group will be used to guide future interventions and support for melanoma and NSCLC patients.

Inclusion Criteria:

1. Patient with melanoma or NSCLC ≥2 years since treatment with at least one cycle of immune checkpoint inhibitor (CTLA-4 inhibitor, PD-(L)1 inhibitor, or both) within the Department of Medical Oncology or Pulmonary Oncology of the UMCG.
2. Age ≥18 years at time of immune checkpoint inhibitor treatment
3. All previous or subsequent therapies allowed, including (brain) irradiation, surgery for metastases, chemotherapy, and targeted therapy, provided stable clinical situation at time of inclusion

Exclusion Criteria:

1. Switch of systemic therapy or local antitumor intervention (surgery, radiotherapy) during last 2 months
2. Inability to understand or abide to the study protocol
3. Debilitating psychiatric illness
4. Previous treatment for malignancy other than melanoma (excluding non-melanoma skin cancer, cervical intra-epithelial neoplasia (CIN) or carcinoma in situ of breast)

An estimated 80 adult patients with advanced melanoma and 250 patients with NSCLC are treated with immune checkpoint inhibitors in the UMCG each year. Around 20% of these patients are expected to survive ≥2 years since their first cycle of immune checkpoint inhibitor. Patients will be recruited and study measurements will be performed within 3 year after start of study. We expect to include 25 melanoma and 50 NSCLC patients per treatment year.