Risk Factors for Cutaneous Immune-Related Adverse Events in the Japanese Population: A Retrospective Single-Center...

Area of Science:

• Oncology
• Immunology
• Dermatology

Background:

• Immune checkpoint inhibitors (ICIs) can cause immune-related adverse events (irAEs).
• Cutaneous irAEs are common and occur early, but risk factors are unclear.
• Understanding these factors is crucial for patient management.

Purpose of the Study:

• To identify risk factors for the development and severity of cutaneous irAEs in patients receiving ICIs.
• To analyze the association between specific ICI therapies and cutaneous irAEs.
• To investigate demographic and hematological factors influencing cutaneous irAE risk.

Main Methods:

• Retrospective analysis of 1224 Japanese patients treated with ICIs from 2014-2024.
• Multivariable logistic regression analysis to identify risk factors.
• Evaluation of ICI type, baseline eosinophil and monocyte counts, sex, and cancer type (melanoma).

Main Results:

• 10.9% of patients experienced cutaneous irAEs; 1.5% had grade 4 events.
• Combination anti-PD-1 and anti-CTLA-4 therapy significantly increased cutaneous irAE risk compared to monotherapy.
• Higher baseline eosinophil counts and melanoma diagnosis were associated with increased cutaneous irAE risk.
• Female sex and high baseline monocyte counts were risk factors for severe (grade 4) cutaneous irAEs.

Conclusions:

• Combination ICI therapy, elevated eosinophils, and melanoma are risk factors for developing cutaneous irAEs.
• Female sex and elevated monocytes are associated with severe cutaneous irAEs.
• These findings aid in predicting and managing ICI-induced skin toxicities.