Meningeal hematopoiesis following radiation myelitis in a hematopoietic stem-cell transplant recipient.
Extramedullary meningeal hematopoiesis (EMH) represents an uncommon finding after stem-cell transplantation. We describe the case of an allogeneic bone marrow transplantation (BMT) recipient who developed EMH 1 month after radiation myelitis had been diagnosed. A 39-year-old man with multiple myeloma underwent matched unrelated BMT following a myeloablative conditioning regimen of cyclophosphamide and total-body irradiation (200 cGyx6). This was followed by delivery of 40 Gy of involved-field radiation to an extramedullary plasmacytoma compressing the spinal cord. Although transplantation went extremely well, the patient developed radiation myelitis 7 months after transplantation, and EMH ensued 1 month later. Because the patient was not in a disease state known to cause EMH, it is tempting to speculate that radiation-related neural injuries might cause donor cells to migrate to the central nervous system.
Sakai
Miwa
M
Hematology Division, Tokyo Metropolitan Komagome Hospital, Tokyo, Japan.
Ohashi
Kazuteru
K
Kobayashi
Takeshi
T
Yamashita
Takuya
T
Akiyama
Hideki
H
Nemoto
Tetuo
T
Kishida
Shuji
S
Kamata
Noriko
N
Sakamaki
Hisashi
H
D000328:Adult; D003131:Combined Modality Therapy; D006411:Hematopoiesis, Extramedullary / Q000528:radiation effects*; D018380:Hematopoietic Stem Cell Transplantation; D006801:Humans; D008297:Male; D008578:Meninges / Q000502:physiology; D009101:Multiple Myeloma / Q000188:drug therapy / Q000532:radiotherapy / Q000628:therapy*; D009187:Myelitis / Q000134:cerebrospinal fluid / Q000209:etiology*; D011832:Radiation Injuries / Q000134:cerebrospinal fluid / Q000209:etiology*; D013116:Spinal Cord / Q000528:radiation effects*; D014916:Whole-Body Irradiation / Q000009:adverse effects