To explore the occurrence, influencing factors, and predictive biomarkers of immune-related adverse events (irAEs) in malignant tumor patients treated with tislelizumab.

The electronic medical records of adult patients with malignant tumors, who received tislelizumab for at least one cycle from June 2020 to June 2023 at Shanghai Ninth People′s Hospital, Shanghai Jiao Tong University School of Medicine, were collected, and the occurrence and clinical characteristics of irAEs were retrospectively analyzed. Patients were divided into irAEs group and non-irAEs group according to whether they had irAEs. The clinical characteristics and detection value of biomarkers in patients of the 2 groups were compared. Multivariate logistic regression was used to analyze the risk factors of irAEs in patients. The receiver operating characteristic (ROC) curve was used to find the cutoff point of the biomarkers for predicting the irAEs.

A total of 107 patients were entered, including 81 males (75.7%) and 26 females (24.3%), aged (61±15) years. Among them, 25 patients (23.4%) were diagnosed with tislelizumab-related irAEs, of which 6 patients (5.6%) had irAEs with a severity of grade 3 and above. A total of 28 irAEs occurred in the 25 patients, including 9 cases of thyroid dysfunction, 4 cases of immune-related enteritis, 4 cases of rashes, 3 cases of immune-related pneumonitis, 3 cases of kidney injury, 3 cases of liver injury, 1 case of immune-related myositis, and 1 case of hypertension. The median treatment cycle from the start of tislelizumab to the occurrence of irAEs was 3 (1, 5) cycles. After discontinuation of tislelizumab and/or glucocorticoids and symptomatic treatments, all 25 patients were improved. No deaths occurred due to irAEs. The results of multivariate logistic regression analysis showed that a high neutrophil-to-lymphocyte ratio (NLP) at baseline was a protective factor for irAEs [odds ratio (OR)=0.453, 95% confidence interval (CI): 0.279-0.735, P=0.001], while a high platelet-to-lymphocyte ratio (PLR) at baseline was a risk factor (OR=1.006, 95%CI: 1.002-1.011, P=0.008). The ROC curve analysis results showed that the cutoff points of NLR and PLR at baseline for predicting the occurrence of irAEs were 1.58 (sensitivity: 0.988; specificity: 0.644) and 159.40 (sensitivity: 0.800; specificity: 0.524), respectively.

The incidence of irAEs in the tislelizumab treatment for adult malignant tumors was 23.4%. Thyroid dysfunction is most common and attentions should also be paid to immune-related enteritis, rashes, immune-related pneumonitis, kidney injury, and liver injury. Baseline levels of NLR and PLR may be biomarkers for predicting irAEs.

Immune checkpoint inhibitors; Drug-related side effects and adverse reactions; Risk factors; Forecasting; Tislelizumab