皮膚慢性移植片対宿主病の反応評価の改善に向けて：国立衛生研究所コンセンサスプロジェクトタスクフォースからの報告

The National Institutes of Health (NIH) chronic graft-versus-host disease (cGVHD) Consensus Project established response criteria that enabled clinical trials and facilitated regulatory approval of multiple therapies. Nonetheless, organ-specific assessments have limitations, particularly for severe sclerotic skin involvement. Cutaneous manifestations occur in approximately half of patients with chronic GVHD but are difficult to evaluate due to heterogeneous clinical features. To address these challenges, the NIH Consensus Skin Task Force convened in 2024-2025 to refine skin response measures for use in clinical trials. This report (a) summarizes current diagnosis and scoring of skin chronic GVHD, (b) reviews existing response assessments, (c) identifies gaps in their performance, (d) proposes refinements to the 2014 NIH skin response criteria, and (e) outlines future directions incorporating patient-reported outcomes, novel technologies, and biomarker research. Current NIH scoring relies on a 4-point body surface area (BSA) scale and a 3-point sclerosis features scale. While standardized, these measures have limited sensitivity to clinically meaningful change. Proposed refinements include: (i) separate BSA assessments for epidermal involvement and sclerotic features; (ii) modification of sclerosis descriptors, with removal of impaired mobility and specification of GVHD-related ulceration, and addition of sclerosis-associated edema with or without erythema; and (iii) replacement of the exploratory severity scale with two new clinician instruments. The Sclerosis Quality and Physical Signs (SQPS) scale (0-10) captures qualitative physical changes, while the Sclerosis Daily Function Impact (SDFI) scale (0-4) evaluates functional compromise. These proposed refinements aim to improve the accuracy, reproducibility, and clinical relevance of skin chronic GVHD assessments, strengthening trial endpoints and patient care.