Background and Importance Immunotherapy has provided better responses and tolerance in the treatment of lung cancer than intravenous chemotherapy. However, it can also induce autoimmune adverse effects that could lead to hospital admission or death of the patient.

Aim and Objectives To analyse possible factors associated with the incidence of immune-related adverse events (iRAEs) in lung cancer (LC) patients treated with immune checkpoint inhibitors (ICI).

Material and Methods Retrospective analysis of patients with LC treated with ICI between 2015 and 2023 in a tertiary hospital. The variables collected from the clinical history were: age, sex, performance status, history of allergy/autoimmune disease, treatment with corticosteroids or antibiotics prior to the ICI, occurrence of iRAEs, type of toxicity and severity, laboratory variables (haemoglobin, neutrophil count, platelet count, LDH), date of progression and death. The association was determined using Chi-square tests and Fisher’s exact test. Progression-free survival (PFS) and overall survival (OS) were calculated using the Kaplan-Meier method

Results A total of 67 patients (74.6% men; mean age 68.6±9.4 years) treated with ICI were analysed. Of these, 49 developed at least one iRAE (73.1%), 37.3% from grade≥3. Statistically significant associations were found between appearance of skin toxicity and altered LDH levels (p=0.048), and musculoskeletal toxicity and ECOG≥2 (p=0.037). History of allergy/autoimmune disease and treatment with corticosteroids or antibiotics in the 3 months prior to the start of immunotherapy were associated with the appearance of liver toxicity (p=0.015 in all cases), asthenia (p=0.027; p=0.021; p=0.032) and musculoskeletal toxicity (p=0.006; p=0.006); p=0.005). Patients with iRAEs had longer PFS (14.8 vs. 3.3 months) and longer OS (19.2 vs. 2.9 months).

Conclusion and Relevance No association was found between the proposed variables and the appearance of immune-related toxicity in general but a significant relation was found between altered LDH and skin toxicity, and between ECOG≥2 and musculoskeletal toxicity. Correlation was also found between a history of allergy or autoimmune disease and the consumption of antibiotics or corticosteroids with the appearance of hepatic, general or musculoskeletal toxicity.

Conflict of Interest No conflict of interest.