Meningeal hematopoiesis following radiation myelitis in a hematopoietic stem-cell transplant recipient

Abstract

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 cGy · 6). 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. Am.

Extramedullary hematopoiesis involving the central nervous system and surrounding structures

“…It most often occurs in cranial meninges [13][14][15][16][17], followed by spinal meninges and paraspinal tissue [7,18], and intracerebral locations [8]. In addition, EMH foci have been reported in central (most often optic nerve) and peripheral nerves [19,20], choroid plexus [21], in and around pituitary gland [22] as well as in orbital [23] and lacrimal fossae [24], and sphenoid sinus [25].…”

Extramedullary haematopoiesis surrounding the pituitary gland after cord blood transplantation

“…To our knowledge, this is the first case report on EMH after CBT. We have little information on EMH after allogeneic bone marrow transplantation (BMT) [4]. As the number of patients with CBT has been much fewer than those with BMT, the frequency and clinical pictures of EMH after CBT are unclear.…”