The Bone Marrow in Myeloproliferative and Dysmyelopoietic Syndromes

Pediatric hyperfibrotic myelodysplasia: an unusual clinicopathologic entity

This study is presented to highlight a rare pediatric bone marrow pathology in which features of bone marrow dysplasia coexist with severe fibrosis in a clinical setting of fever, anemia, and organomegaly. Fourteen children (nine males, five females) clinically presented with fever, anemia, and hepatosplenomegaly. Extensive bone marrow fibrosis with dysplastic features was seen in their marrow precursor cells. Peripheral blood smears showed teardrop poikilocytes thrombocytopenia, and occasional blasts. In conclusion, pediatric hyperfibrotic myelodysplasia is a distinct clinicopathologic entity. Myeloproliferative and dysmyelopoietic syndromes are complex disorders that are interrelated and not always easily diagnosed only on morphologic grounds.

Potential of bone marrow biopsy in chronic myeloproliferative disorders (MPD)

The chronic myeloproliferative disorders (MPD) comprise polycythemia vera (PV), idiopathic thrombocythemia (IT), chronic myeloid leukemia (CML) and myelofibrosis/osteomyelosclerosis (MF/OMS). Bone marrow biopsies of 3500 patients with known or suspected MPD were studied, and the clinical and morphologic variables registered were utilized for multivariate data analysis by selected BMD computer programs. The histologic criteria and the histologic subdivisions, as well as the evolution and prognosis of disease are outlined for each of the clinical entities. The results show that a bone marrow biopsy provides independent diagnostic and prognostic data in this group of hematologic malignancies and therefore constitutes an additional parameter in the diagnostic investigation of patients with suspected or established MPD.

Secondary myelodysplastic syndrome complicating therapy for osteogenic sarcoma

A 12-year-old girl with nonmetastatic osteogenic sarcoma received treatment with doxorubicin, methotrexate, cisplatin, cyclophosphamide, bleomycin, and dactinomycin. She developed unexplained persistent pancytopenia after completion of chemotherapy. Twenty-three months after the initial diagnosis of osteosarcoma an evaluation revealed a bone marrow pattern consistent with the diagnosis of refractory anemia with excess blasts, and karyotype analysis showed characteristic findings of therapy-related myelodysplasia (loss of chromosomes 5 and 7, as well as 12p and 17p deletions). Bone marrow transplantation from an human leukocyte antigen (HLA)-compatible sibling donor was performed 26 months after the diagnosis of the primary malignancy. Although it is unproven that the alkylating agents administered to this patient were responsible for the myelodysplastic syndrome, careful follow-up of osteosarcoma patients who receive alkylating agents is warranted.

Are 'dysplastic' and hypogranular megakaryocytes specific markers for myelodysplastic syndrome?

Dysmegakaryocytopoiesis is an integral component of myelodysplastic syndrome (MDS), and has been shown in some studies to be an independent prognostic factor. Megakaryocytic hypogranulation, a feature we have noticed for some time to be fairly common in MDS and acute myeloid leukaemia (AML), has received little attention in the literature as a dysplastic feature of megakaryocytes. This study was performed to determine how frequently this feature was observed in MDS and the specificity of its occurrence. On review of archival materials, hypogranular megakaryocytes were observed in 80.3% of MDS, 30.6% of AML and 1.4% of controls. On the other hand, the other well-recognized dysmegakaryocytopoietic features (hypolobulation, multiple separate nuclei, micromegakaryocyte), though frequent in MDS or AML, were also observed in 20% of controls. We therefore propose including megakaryocytic hypogranulation as a cytological feature of myelodysplasia.