Successful treatment of scleromyxedema with autologous peripheral blood stem cell transplantation

Background: Scleromyxedema is a rare chronic fibromucinous disorder that can have devastating clinical manifestations, including sclerosis of the skin with progressive pharyngeal and upper airway involvement, resulting in high mortality due to respiratory complications. Herein we describe a novel therapeutic approach. Because autologous hematopoietic stem cell transplantation is effective in other plasma cell proliferative disorders, it may be effective in this setting. Observations: We retrospectively evaluated 6 patients who were offered high-dose chemotherapy with stem cell rescue as treatment for scleromyxedema. One heavily pretreated patient was unable to mobilize stem cells. The remaining 5 patients mobilized stem cells and underwent successful transplantation. There was no treatment-related mortality. Hematologic responses were seen in 4 patients, including 2 complete remissions and 2 partial remissions, and all 4 had improvement in extracutaneous manifestations. All 4 patients subsequently had relapse of the monoclonal protein, and 3 developed skin relapses at 14, 37, and 45 months. Conclusions: High-dose chemotherapy with stem cell rescue is feasible for patients with scleromyxedema and, although not curative, offers durable remission in most patients. This therapy should be considered before treatment with alkylating agents or other treatments that could adversely affect the ability to collect stem cells.