LY02 Dupilumab use in atopic dermatitis when cutaneous lymphoma is suspected: consensus recommendations from the EORTC Cutaneous Lymphoma Tumour Group

Dupilumab is highly effective for moderate-to-severe atopic dermatitis (AD). However, increasing reports of cutaneous T-cell lymphoma (CTCL), particularly mycosis fungoides (MF) and Sézary syndrome (SS), diagnosed during or after therapy, have raised concern. Although causality is unproven, interpretation is complicated by diagnostic overlap between AD and CTCL and by detection and surveillance bias. We aimed to develop practice-oriented, consensus-based recommendations for dupilumab use when CTCL is suspected. Clinical consensus recommendations were developed by a panel of European CTCL specialists, including members of the EORTC Cutaneous Lymphoma Tumour Group. A structured questionnaire comprising 12 predefined statements was informed by a focused narrative review of clinical, epidemiological and mechanistic evidence derived from retrospective cohorts, pharmacovigilance analyses and case series. Levels of agreement were assessed for each statement; areas of uncertainty were identified, discussed and addressed within the final recommendations. High consensus was achieved across the panel. Dupilumab remains appropriate for well-defined, moderate-­to-severe AD. However, dupilumab should be avoided in patients with suspected or confirmed MF or SS. In atypical or treatment-refractory AD – particularly adult-onset disease without prior atopic history – clinicians should maintain a high index of suspicion for CTCL, with a low threshold for skin biopsy, clinicopathological correlation, T-cell clonality assessment and peripheral blood evaluation when clinically indicated. During dupilumab therapy, lack of clinical response, disease worsening or emergence of atypical features should prompt timely reassessment for CTCL rather than treatment escalation. In concomitant AD and CTCL, or in palliative contexts, dupilumab may be considered only after multidisciplinary discussion and individualized risk–benefit evaluation; where available, alternative agents may be preferred. These recommendations provide a cautious, practical approach to minimize diagnostic anchoring and delayed CTCL recognition while preserving access to dupilumab for appropriately selected patients with AD. Prospective studies are needed to better define risk and refine patient selection.