Chronic graft-versus-host disease-related polymyositis and myocarditis: A case report and review of the literature.

Chronic graft-versus-host disease (cGVHD) is a major late complication of hematopoietic stem cell transplantation (HSCT). Polymyositis (PM) has been reported to be an uncommon presentation of cGVHD. Myocarditis is an even rarer manifestation of cGVHD-associated PM. Here, we report a 38-year-old male patient developed cGVHD-related PM twelve years post-transplantation, which was confirmed by muscle biopsy and immunological study. The presence of pain in the chest area, dynamic changes in the electrocardiogram, as well as elevated troponin and myocardial enzyme levels with improvement after immunotherapy all pointed to cardiac involvement. Ruxolitinib in combination with tachlimus and methylprednisolone successfully treated cGVHD associated PM with myocarditis. The literature on cGVHD-related PM and myocarditis is briefly reviewed.