Development of solitary plasmacytoma in the internal auditory canal and inner ear after allogeneic hematopoietic stem cell transplantation for plasma cell leukemia.

Here we report the first case of the development of intracranial solitary plasmacytoma in the inner ear after allogeneic stem cell transplantation (allo-SCT) in a 39-year-old Japanese female with primary plasma cell leukemia (PCL). A point to note is that this is not a case on multiple myeloma but on PCL. She was successfully treated with local irradiation and survived more than 6 years from the time of diagnosis and transplantation. This case elucidates the biology of PCL and stresses the need for an individual approach to the clinical management of patients with plasma cell neoplasm undergoing allo-SCT.