Bone marrow transplantation: clinical and radiologic aspects.

With the advent of histocompatibility typing, use of bone marrow transplantation for treating hematogenous cancer has dramatically increased. Marrow grafting is preceded by intense immunosuppressive, marrow ablative treatment, usually with high-dose chemotherapy and whole-body irradiation. Because the recipient may be immunocompromised for months after transplantation due to this regimen, complications are numerous. Complications are classified according to the following intervals: pre-engraftment (from pretransplantation treatment to engraftment), postengraftment (3 months afterward), and delayed (longer than 3 months after engraftment). Pre-engraftment complications include bacterial, fungal, and viral infections; tissue-damaging effects (eg, toxic pneumonitis); hepatic veno-occlusive disease; and graft rejection. Postengraftment complications include viral, fungal, and protozoal infections; acute graft-versus-host disease (GVHD); and pneumatosis intestinalis. Delayed complications include chronic GVHD and recurrence of cancer. As part of the follow-up team, radiologists should be familiar with clinical aspects of marrow transplantation and be alert for early, potential life-threatening complications.