Inflammatory pseudotumor of the brain following hematopoietic stem cell transplantation

Central nervous system graft-versus-host disease (CNS-GvHD) after allogeneic haematopoietic stem cell transplantation

A 60-year-old man presented with impaired consciousness and psychomotor agitation after a second allogeneic haematopoietic stem cell transplantation (HSCT) from a matched unrelated donor for acute myeloid leukaemia. Clinical, biological and radiological evidence suggested a diagnosis of central nervous system graft-versus-host disease (CNS-GvHD). After intrathecal infusion of methylprednisolone, the clinical symptoms as well as the radiological abnormalities disappeared. The present report illustrates the difficulties in the diagnosis and the management of CNS-GvHD, a very rare and still challenging neurological complication that can occur after allogeneic HSCT.

Neurological complications of hematopoietic cell transplantation in children and adults

Hematopoietic cell transplantation (HCT) is widely performed for neoplastic and non-neoplastic diseases. HCT involves intravenous infusion of hematopoietic progenitor cells from human leukocyte antigen (HLA)-matched donor (allogeneic) or from the patient (autologous). Before HCT, the patient is prepared with high dose chemotherapy and/or radiotherapy to destroy residual malignant cells and to reduce immunologic resistance. After HCT, chemotherapy is used to prevent graft rejection and graft versus host disease (GvHD). Neurological complications are related to the type of HCT, underlying disease, toxicity of the conditioning regimens, immunosuppression caused by conditioning regimens, vascular complications generated by thrombocytopenia and/or coagulopathy, GvHD and inappropriate immune response. In this review, neurological complications are presented according to time of onset after HCT: (1) early complications (in the first month) - related to harvesting of stem cells, during conditioning (drug toxicity, posterior reversible encephalopathy syndrome), related to pancytopenia, (2) intermediate phase complications (second to sixth month) - central nervous system infections caused by prolonged neutropenia and progressive multifocal leukoencephalopathy due to JC virus, (3) late phase complications (after sixth month) - neurological complications of GvHD, second neoplasms and relapses of the original disease.

Aggressive Metastatic Inflammatory Myofibroblastic Tumor After Allogeneic Stem Cell Transplant With Fatal Pulmonary Toxicity From Crizotinib

Inflammatory myofibroblastic tumors (IMTs) are rare tumors with an intermediate spectrum of biological behavior. IMTs are uncommon secondary malignancies after hematopoietic stem cell transplant. The presence of anaplastic lymphoma kinase rearrangements in 50% of IMTs has led to therapeutic trials with crizotinib, although limited experience remains with crizotinib use in children. We describe the first reported case of a highly aggressive and metastatic IMT (secondary malignancy) in an 8-year-old girl following umbilical cord blood transplant. Although tumor response was demonstrated with anaplastic lymphoma kinase inhibition, she later developed fatal pulmonary toxicity from diffuse alveolar damage, a feature felt most likely to be due to crizotinib.

Inflammatory Pseudotumors After Stem Cell Transplantation

Inflammatory pseudotumors (IPT) are rare tumors that occur in various organs and tissues. The clinical picture varies from the more frequent benign lesions to rare malignant tumors with distant metastases. IPTs associated with hematopoietic stem cell transplantation (HSCT) is rarely reported. In this article, we review the reports of IPT after HSCT. We also review the possible factors involved in the pathogenesis. IPT may be rare but they are a potentially serious complication of HSCT. A knowledge of these entities and insistence on a definitive biopsy of mass lesions in the post-HSCT period can avoid unnecessary treatment such as radical surgery, chemotherapy or radiotherapy.

An endobronchial inflammatory myofibroblastic tumor in a 10-yr-old child after allogeneic hematopoietic cell transplantation

IMTs belong to the group of soft tissue tumor and could occur at any anatomical site; however, the causes and growth feature remain unclear. This case report documents a 10-yr-old male suffering from slowly developing dyspnea on exertion and cough around seven months post-HCT. He was diagnosed with an endobronchial tumor based on imaging, and histology confirmed ALK-positive submucosal spindle-shaped cells with infiltrative cells, compatible with IMT. We should be aware that IMT is a potential complication of pediatric allogeneic HCT and can cause sudden airway obstruction.

Neurological complications of transplantation: part I: hematopoietic cell transplantation

Hematopoietic cell transplantation (HCT) is the preferred treatment for an expanding range of neoplastic and nonmalignant conditions. Increasing numbers of solid organ transplantations (SOTs) add an additional population of immunosuppressed patients with multiple potential neurological problems. While the spectrum of neurological complications varies with conditioning procedure and hematopoietic cell or solid organ source, major neurological complications occur with all transplantation procedures. This 2 part review emphasizes a practical consultative approach to central and peripheral nervous system problems related to HCT or SOT with clinical and neuroimaging examples from the authors' institutional experience with the following conditions: the diversity of manifestations of common infections such as varicella zoster virus, Aspergillus, and progressive multifocal leukoencephalopathy (PML), drug therapy-related complications, stroke mechanisms, the spectrum of graft versus host disease (GVHD), and neurologically important syndromes of immune reconstitution inflammatory syndrome (IRIS), posterior reversible encephalopathy syndrome (PRES), and posttransplantation lymphoproliferative disorder (PTLD). These complications preferentially occur at specific intervals after HCT and SOT, and neurological consultants must recognize an extensive spectrum of syndromes in order to effect timely diagnosis and expedite appropriate treatment.

Inflammatory pseudotumor following hematopoietic stem cell transplantation: a new case and review of the literature

Inflammatory pseudotumor (IPT) is a rare tumor that occurs in various organs and tissues. The clinical picture varies from the more frequent benign lesions to the rare malignant tumors with distant metastases. IPT associated with hematopoietic stem cell transplantation (HSCT) is rarely reported. In this article, we review the reports of IPT after HSCT and describe the first case of bladder IPT. We also review the possible factors involved in the pathogenesis. IPT might be rare but it is a potentially serious complication of HSCT. It should be considered in patients with otherwise unexplained inflammatory symptoms or signs or with any mass lesion in the post-HSCT period. A knowledge of this entity and insistence on a definitive biopsy of mass lesions in the post-HSCT period can avoid unnecessary treatment such as radical surgery, chemotherapy or radiotherapy.