Immune checkpoint inhibitors appear safe in cancer patients with pre-existing sarcoidosis

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Critical reviews in oncology/hematology Published June 1, 2026 Medically reviewed June 1, 2026 Study authors: Martella Serafina, Cusumano Giacomo, Stylianakis Dimitrios, Wolff Louis, Porcu Michele, Lambertini M… PubMed ↗ DOI ↗ By Dr. Amelia Tan, PhD · Internal Medicine & Chronic Disease

Key Takeaway

Consider ICI therapy in cancer patients with pre-existing sarcoidosis, but monitor for mild-to-moderate flares.

This meta-analysis assessed the safety of immune checkpoint inhibitors (ICIs) in cancer patients with documented pre-existing sarcoidosis. The analysis included 43 patients from published reports. The primary outcome was sarcoidosis flare or reactivation during ICI therapy.

The authors found that 93.0% of patients showed no reactivation. The pooled prevalence of flare was 19.6%, with higher rates observed with anti-CTLA-4 inhibitors compared with anti-PD-1/PD-L1 agents or mixed regimens. Flares were generally mild to moderate, and no fatal or irreversible reactivations were reported. Permanent discontinuation of ICI therapy was rarely required.

Key limitations include a sparse event count and limited reported events. The authors emphasize that prevalence estimates should be interpreted as exploratory. The analysis is based on a small cohort and may not be generalizable.

Clinically, these findings suggest that ICIs may be used cautiously in patients with pre-existing sarcoidosis, with monitoring for flares. However, the exploratory nature of the data warrants careful patient selection and discussion of risks.

Study Details

Study typeMeta analysis

EvidenceLevel 1

PublishedJun 2026

PMID41865918

View Original Abstract ↓

BACKGROUND: The use of immune checkpoint inhibitors (ICIs) in patients with pre-existing sarcoidosis raises concerns about disease reactivation. However, the incidence and clinical implications of sarcoidosis flare under ICI therapy remain poorly defined. Given the rarity of this scenario and limited reported events, this quantitative synthesis aimed to provide an exploratory summary of the available evidence and its uncertainty. METHODS: A pooled analysis included seven published studies, primarily retrospective cohorts and case series, comprising 43 cancer patients with documented pre-existing sarcoidosis treated with ICIs. Data on flare occurrence, ICI class, management, and oncologic outcomes were extracted. The pooled prevalence of flare was estimated using a random-effects model with logit transformation and continuity correction. Sensitivity analyses for rare events included exact binomial confidence intervals around the crude proportion and an alternative pooled estimate without continuity correction. Heterogeneity was assessed using Cochran's Q, I², and τ² statistics. RESULTS: Overall, 93.0% of patients showed no reactivation. The pooled prevalence of flare was 19.6% (95% CI: 8.1-40.3) with low heterogeneity (Q = 7.00, p = 0.32; I² = 14.3%; τ² = 0.27). Flares were mild to moderate and managed with corticosteroids, rarely requiring permanent discontinuation. Subgroup analysis showed higher flare rates with anti-CTLA-4 inhibitors (25%) compared with anti-PD-1/PD-L1 agents (14.3%) and mixed regimens (3.1%). No fatal or irreversible reactivations were reported. CONCLUSIONS: Sarcoidosis flare under ICI therapy appears uncommon and generally manageable; however, prevalence estimates should be interpreted as exploratory given sparse event count.