Independent risk factor of drug eruption in immune checkpoint inhibitors treated liver cancer patients: high systemic immune-inflammation index.

Purpose: The clinical application of immune checkpoint inhibitors (ICIs) has significantly improved the prognosis of liver cancer patients. However, drug eruption associated with ICI monotherapy or combination therapy not only impacts the quality of life and treatment progress of liver cancer patients but also poses a potential threat to their lives. The study aims to investigate the risk factors of drug eruption in liver cancer patients undergoing ICIs in real-world settings.

Methods: We retrospectively collected data from liver cancer patients who underwent ICI therapies at the Third Affiliated Hospital of Sun Yat-sen University between 2021 and 2022. A propensity score matching (PSM) method was employed to match 31 liver cancer patients with ICI-related drug eruption (drug eruption group) to 228 liver cancer patients without immune-related adverse reactions (control group) in a 1:2 ratio, creating two groups of patients with comparable baseline characteristics. Subsequently, logistic regression analysis was then conducted to analyze the clinical risk factors associated with drug eruption caused by ICIs.

Results: Before PSM, there were statistically significant differences between the drug eruption group (31 cases) and the control group (228 cases) in two variables: Child-Pugh liver function classification and presence of vascular invasion (both p < 0.05). However, after PSM, no statistically significant differences were found in the clinical variables between the drug eruption group (28 cases) and the control group (52 cases). Univariate analysis revealed significantly higher levels of aspartate amino-transferase, alanine aminotransferase, glutamyl transpeptidase, and systemic immune-inflammation index (SII) and a significantly lower rate of liver cancer resection surgery before immunotherapy in liver cancer patients with drug eruption compared to the control group (p < 0.05). Multivariate analysis indicated that an elevated SII level before immunotherapy was significantly associated with the occurrence of drug eruption in liver cancer patients treated with ICIs (p < 0.05). The predictive performance of SII before immunotherapy in liver cancer patients for ICI-related drug eruption yielded an area under the receiver operator characteristic curve of 0.852, with a critical value of 749.189. Sensitivity and specificity were determined as 85.7% and 75%, respectively (p < 0.05).

Conclusions: Elevated systemic immune-inflammation index is identified as a risk factor for drug eruption occurrence in liver cancer patients treated with ICI therapies.