Abstract
BACKGROUND: Cutaneous monoclonal gammopathy of clinical significance (MGCS) is rare and may present with scleredema-like fibrosing skin disease. CASE: A 59-year-old man developed progressive induration of the upper body. Laboratory studies revealed an IgG/κ monoclonal protein, and skin biopsy showed dermal thickening with mucin deposition. He was refractory to corticosteroids, immunosuppressants, IVIG, plasmapheresis, and bortezomib. RESULTS: Daratumumab monotherapy led to rapid improvement after 4-5 cycles, sustained over 20 cycles, with mobility recovery, mRSS reduction, paraprotein disappearance, and partial histologic regression. CONCLUSION: Daratumumab may represent an effective clone-directed therapy for refractory MGCS-associated scleredema. Trial Registration: The authors have confirmed clinical trial registration is not needed for this submission.