BackgroundImmunotherapy is currently applied in the first-line treatment regimens for numerous advanced cancers, especially advanced lung cancer. Immune-related adverse events (irAEs) resulting from immunotherapy can vary in severity and cause a substantial symptom burden to patients. However, there are limited data on symptom burden in patients with advanced lung cancer following immunotherapy. To address this deficit, this study aims to provide insight into the symptom burden and severity through patient-reported outcome measurements and conduct an analysis of temporal trends and clinical consequences of symptom burden in patients with advanced lung cancer receiving combination immunotherapy.MethodsWe will prospectively recruit 168 eligible patients from 14 hospitals in China. Eligible patients will be aged ≥ 18 years, pathologically diagnosed with locally advanced or stage IV primary lung cancer without surgical indications, and agreed to receive immunotherapy in combination with other therapies. The primary outcome of this study is the symptom burden of patients during the immunotherapy course. Longitudinal symptom data will be collected using the MD Anderson Symptom Inventory–Lung Cancer module (MDASI-LC) and the symptomatic irAEs scale at baseline (once before treatment) and weekly after treatment, until 1 month after the last treatment cycle has been completed. The trajectory of symptom burden following combination immunotherapy will be depicted, and by linking it to clinical outcomes (the secondary outcome and exploratory outcome of this study), the consequence of symptom burden in patients with advanced lung cancer receiving combination immunotherapy will be examined further.DiscussionThis study intends to establish longitudinal symptom trajectories in patients with lung cancer receiving immunotherapy, and explore its association with clinical outcomes. These findings may serve as an important reference for clinicians in the symptomatic management of patients with lung cancer receiving immunotherapy.Trial registration numberChiCTR2200061540. Registered on June 28, 2022.