Toxicity spectrum and risk factors for chemo-immunotherapy in locally advanced or metastatic lung cancer

Chemo-immunotherapy has become the best first-line treatment for advanced lung cancer patients without oncogenic drivers. However, it may also lead to an increased incidence and severity of treatment-related adverse events. In this retrospective study, lung cancer patients administrated with either anti-PD-1 or anti-PD-L1 treatment plus chemotherapy were included. Data on demographic characteristics, disease characteristics, treatment strategies, laboratory results, and clinical outcomes were collected from the Electronic Medical Records System and evaluation scales. Chi-square, univariate, and multivariate logistic regression analyses were used to identify the risk factors for immune-related adverse events (irAEs). A total of 116 patients were included in the study, and the majority experienced treatment-related adverse events. Adverse events of any grade were reported in 114 (98.3%) patients, with 73 (62.9%) experiencing Grade 3 or higher events. The most frequent adverse events were anemia (67.2%), decreased appetite (62.9%), and alopecia (53.4%). Fifty-four (46.6%) patients were diagnosed with irAEs, with hypothyroidism (28.4%) being the most commonly reported. Multivariable analysis demonstrated a significant correlation between the number of treatment cycles, elevated baseline levels of thyroid stimulating hormone (TSH) and interleukin-6 (IL-6) with irAEs (OR = 1.222, P = 0.009, OR = 1.945, P = 0.016, OR = 1.176, P = 0.004), and IL-6 was identified as a strong predictor of severe irAEs (OR = 1.084, P = 0.014). Our study demonstrated the safety of chemo-immunotherapy in lung cancer patients without additional toxicity. The number of treatment cycles, higher baseline levels of TSH and IL-6 were identified as potential clinical biomarkers for irAEs.