High dose chemotherapy and allogenic peripheral blood stem cell transplantation for multiple myeloma evolving from intra-abdominal plasmacytoma.

Solitary plasmacytomas include extramedullary plasmacytomas and those found in the bone. Seventy percent of patients are male and the median age is 50-55 years, younger than that for plasma cell myeloma. Most solitary plasmacytomas of bone eventually evolve to plasma cell myeloma within 2-10 years, while the extramedullary ones do so infrequently. We present an unusual case of intra-abdominal plasmacytoma in a young woman which was misdiagnosed and treated as T cell lymphoma initially. Typical manifestations of plasma cell myeloma appeared one year later. High dose chemotherapy followed by allogeneic peripheral stem cell blood transplantation (allo-PBSCT) was given. Relapse in skin occurred one year after allo-PBSCT, and was treated with wide excision and local irradiation. The patient was well and alive without evidence of disease 4 years after wide excision of the recurrence of chest wall solitary plasmacytoma and local radiotherapy.