Atopic dermatitis severity and treatment history predict cutaneous T-cell lymphoma outcomes

Summary: Abstract Body: We previously demonstrated that a history of atopic dermatitis (AD) impacts cutaneous T-cell lymphoma (CTCL) outcomes. However, the influence of AD severity remains unknown. In this retrospective analysis of 211 CTCL patients with a documented AD history (2011–2024) at a tertiary referral center, we investigated how AD severity, defined by treatment intensity, influenced CTCL outcomes. Mycosis fungoides predominated (90%) over Sézary syndrome (10%) in our diverse cohort (50.7% female; 49.3% White, 47.9% Black, 2.8% Asian; mean age at diagnosis: 54.5 ± 16.3 years). AD severity was stratified based on treatment intensity: mild-to-moderate disease (n=131) managed with topical corticosteroids and/or phototherapy, versus severe disease (n=80) requiring systemic immunotherapy (including corticosteroids, JAK inhibitors, biologics) with or without adjunctive topicals or phototherapy. Multivariate analysis controlled for age at CTCL diagnosis, sex, and race. Patients classified as having severe AD based on prior systemic therapy use had higher odds of advanced-stage CTCL at diagnosis (OR=2.24, 95% CI: 1.16–4.38, p=0.017) and folliculotropic CTCL (OR=2.65, 95% CI: 1.29–5.54, p=0.008). Survival time was reduced by 3.3 years in the severe AD group (95% CI: 2.3–4.2 years, p=0.001). Traditional prognostic markers, including eosinophil counts and lactate dehydrogenase levels, were comparable between AD severity groups, suggesting that other factors such as prior systemic therapy may influence CTCL outcomes. There were no significant differences between severe and mild-to-moderate AD groups in infection-related complications (bacteremia: 19.8% vs 15.3%, p=0.300; cellulitis: 32.1% vs 28.2%, p=0.163; pneumonia: 12.3% vs 20.6%, p=0.695) or comorbidities, including hyperlipidemia (58.0% vs 64.1%, p=0.326) and hypertension (46.9% vs 57.3%, p=0.659). Our findings suggest that AD severity and/or its management may impact CTCL progression and survival. Our ongoing analyses aim to identify specific immune and therapeutic mechanisms driving these outcomes. Sara Khoshniyati¹, Abigail Fleischli¹, Jeffrey Weiner¹, Olivia Pierog¹, Sima Rozati¹ 1. Dermatology, The Johns Hopkins University School of Medicine, Baltimore, MD, United States. Clinical Research: Epidemiology and Observational Research