(SLB-024) Improved Survival Outcomes in Cancer Patients with Autoimmune Skin Diseases Receiving Immune Checkpoint Inhibitors: A Nationwide Cohort Study

Background: Immune checkpoint inhibitors (ICIs) have transformed cancer treatment by enhancing T cell-mediated immune responses, demonstrating significant efficacy across various malignancies. Autoimmune skin diseases (ASDs) are characterized by immune dysregulation, particularly Th1/Th17 polarization and T cell dysfunction, which may influence cancer progression and treatment efficacy. However, the impact of ASDs on survival outcomes in cancer patients receiving ICIs remains unclear.

Objectives: This study aimed to evaluate the association between ASDs and survival outcomes in cancer patients treated with ICI therapy.

Methods: This population-based cohort study used data from the Taiwan National Health Insurance Database. Adults aged ≥18 years who initiated ICI treatment between 2019 and 2021 were included. Patients were categorized into two groups: those with at least one diagnosis of alopecia areata, Sjögren’s syndrome, vitiligo, psoriasis, lichen planus, cutaneous lupus erythematosus, autoimmune bullous diseases, systemic sclerosis, morphea, hidradenitis, or dermatomyositis were classified into the ASD group, while those without these conditions comprised the non-ASD group. The primary outcome was all-cause mortality. Inverse probability of treatment weighting (IPTW) was conducted to balance confounders. Kaplan–Meier survival analysis with log-rank tests was used to compare mortality risk between groups, and Cox proportional hazards regression models were applied to estimate adjusted hazard ratios (HRs) and 95% confidence intervals (CIs).

Results: A total of 377 patients were included in the ASD group and 2,617 patients in the non-ASD group, with a follow-up period of 2,603 person-years. The mortality incidence rates were 66.18 per 100 person-years in the ASD group and 78.94 per 100 person-years in the non-ASD group. Patients with ASDs had a 13% lower risk of mortality than those without ASDs (IPTW-aHR: 0.87, 95% CI: 0.76–0.99). Among ASD subtypes, vitiligo (IPTW-aHR: 0.43, 95% CI: 0.21–0.90) and Sjögren’s syndrome (IPTW-aHR: 0.75, 95% CI: 0.60–0.93) demonstrated the most significant survival benefits. Sensitivity analyses confirmed the robustness of these findings.

Conclusions: This nationwide cohort study demonstrated that cancer patients with ASDs treated with ICIs had significantly improved survival outcomes. These findings suggest that ASDs may modulate the tumor-immune microenvironment, potentially enhancing ICI efficacy. Further research is needed to clarify the underlying mechanisms and explore how these insights can be translated into improved cancer immunotherapy strategies.