Histopathology of the bone marrow in toxic myelopathy. A study of drug induced lesions in 57 patients

Hematopoietic recovery following chemotherapy is improved by BADGE-induced inhibition of adipogenesis

This study was designed to investigate the role of increased adipocytes in the bone marrow (BM) niche induced by high-dose chemotherapy in hematopoietic recovery. Arabinosylcytosine (Ara-C) was administered to adult C57BL/6J mice to induce adipogenesis in the BM. We investigated the effects of adipogenesis on hematopoietic recovery following chemotherapy, using the peroxisome proliferator-activated receptor gamma inhibitor, bisphenol A diglycidyl ether (BADGE). Adipocyte hyperplasia could be induced by Ara-C treatment in BM and inhibited by BADGE. The accelerated recovery of leukocyte counts, increased colony forming units, and a higher proportion of Ki67(+)CD45(+) BM cells and Ki67(+)Lin(-)Sca1(+)c-kit(+) hematopoietic stem cells were observed in the long bone marrow of adipocyte-inhibited mice, as well as an increase in the number of CD45(+) BM cells in the tail fatty marrow compared to controls. Adipocytes participated in creating a distinctive niche for hematopoietic cells. In addition, lower expression of stromal cell-derived factor-1α and hypoxia-inducible factor-1 alpha were detected in the BADGE-treated group. These results indicate that hematopoietic recovery is improved following chemotherapy in adipogenesis-inhibited mice. In addition, adipocytes may create an individual niche that affects the proliferation and migration of hematopoietic cells in vitro and in vivo.

Morphology of the bone marrow after stem cell transplantation

In many haematological conditions the only curative option is stem cell (SCT) or bone marrow (BM) transplantation. Little information exists about BM morphology following non-ablative engraftment. During the pretransplantation period and depending on the kind of pretreatment, there may be hypoplasia, residual disease and varying degrees of fibrosis. In the post-transplantation period, after 1-3 weeks of transfusion-dependent pancytopenia, the first signs of successful engraftment are indicated by the recurrence of neutrophils, monocytes and erythrocytes in the peripheral blood. In the BM there is slow regeneration of erythropoiesis, followed by the other lineages of haematopoiesis and increase in reticulin fibres or even a resolution of fibrosis. Diagnostic problems arise when neoplastic lympho- or haematopoiesis are maintained following transplantation. Moreover, there may be a significant graft versus tumour response reaction or an already relapsing disease needing aggressive treatment. On the other hand, a conspicuous dyshaematopoiesis should not be mistaken as representing a myelodysplastic syndrome. The presence of granulomas being treatment-related or a manifestation of intercurrent granulomatous disease has to be considered. More advanced knowledge of the histological features of regenerating BM will certainly aid the recognition of relapsing disease and is needed for the adequate reporting of post-transplant alterations associated with a successful or failing engraftment.

Hematologic aspects of myeloablative therapy and bone marrow transplantation

The transplantation of bone marrow cells or isolated hematopoietic stem cells from the bone marrow or peripheral blood is a widely utilized form of therapy for patients with incurable diseases of the hematopoietic and immune systems. Successful engraftment of the transplanted stem cells in an adequately prepared recipient normally leads to bone marrow reconstitution over a period of several weeks, accompanied by more gradual reconstitution of the immune system. Since the recipient is profoundly ill during the initial treatment period, laboratory data is critical for monitoring engraftment, detecting residual/recurrent disease, and identifying problems that may delay bone marrow reconstitution or lead to other medical complications. Accurate blood cell counts are imperative, and most bone marrow transplantation patients undergo periodic monitoring with bone marrow aspirates and biopsies with cytogenetic, molecular, and multiparametric flow cytometric studies. The potential complications of bone marrow transplantation include engraftment failure and delayed engraftment, infection, residual bone marrow disease, acute and chronic graft versus host disease, myelofibrosis, therapy-related acute leukemia, post-transplant lympho-proliferative disorders, and toxic myelopathy.

Bone marrow trephine biopsy in lymphoproliferative disease

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Autopsy and clinical findings in acute leukemia and chronic myeloproliferative diseases--an evaluation of 104 patients

In acute myeloid leukemia (AML-46 patients) and various entities of chronic myeloproliferative diseases (CMPD-58 patients) an evaluation and comparison of clinical and postmortem findings has been performed. This study included also aspirates and core biopsies of the bone marrow which were initially taken on admission of those patients. Classification of CMPD was done following the concept of Georgii et al. (1984) into CGL -24-, CMGM-6-, E-MS-13- and MS/OMS-15 cases. There was a significant increase in blastic crisis in CGL compared with the other entities and in the latter a prolongation of the total course of disease due to a long period between symptoms--clinical diagnosis. As revealed by the autopsies causes of death were mostly infections (pneumonia, septicemia-50%) and lethal hemorrhages (gastrointestinal and cerebral--about 30%) in both AML and CMGM patients. Rare causes comprised fatal pulmonary embolism due to a peripheral thrombocytosis in CMPD, acute rupture of the spleen and extensive leukemic infiltrates of the myocard in AML. In addition to the well known giant enlargement of the spleen in MS/OMS, the relatively high frequency of a meningeal involvement (meningeosis leukemica) in AML (about 35%) and during an acute transformation in CMPD (up to 30%) was conspicuous. The examination of the bone marrow at various sites became feasible during the postmortem procedure and thus provided the opportunity to investigate the development and extent of a myelosclerosis evolving in CMPD. In contrast to the a- or hypoplasia and regeneration of the hematopoiesis following chemotherapy, the evolution of myelosclerotic lesions showed a very uniform pattern throughout the skeleton and obviously no reversal of a manifest MS/OMS after cytotoxic treatment.