Tc-99m MDP bone scintigraphy of myositis as a manifestation of chronic graft-versus-host disease after non-myeloablative peripheral stem cell transplantation.

A 27-year-old man developed polymyositis as a manifestation of chronic graft-versus-host disease (GVHD) after non-myeloablative peripheral blood stem cell transplantation (PBSCT). Bone scintigraphy showed intense, striped, and heterogeneous accumulation of Tc-99m methylene diphosphonate (MDP) in the soft-tissue of his lower limbs, while faint activities were seen in the right upper limb. Tc-99m MDP scintigraphy was very useful for accurate and objective evaluation of the severity of the muscle injury and the extent of polymyositis caused by chronic GVHD.