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A case of idiopathic myelofibrosis with alloimmunization to HLA-identical platelet transfusions not responsive to antibody absorption over protein-A columns.

A case of idiopathic myelofibrosis has been treated with HLA-identical platelet apheresis concentrates. After a short period the patient also developed refractoriness to the haploidentical siblings. Protein A columns were used to absorb the platelet antibodies with no result. Now two apheresis platelet concentrates are used every month, crossmatched negative products produce good results maintaining cell counts between 20 and 30 x 10(9)/L. The immune mechanism involved is difficult to understand.

Adult↗

Allogeneic hematopoietic cell transplantation following reduced intensity conditioning for treatment of myelofibrosis.

This report describes our experience with reduced intensity conditioning (RIC) allogeneic hematopoietic cell transplantation (HCT) using matched sibling and unrelated donors (MUDs) for treatment of myelofibrosis (MF). Nine patients with MF (median age, 54 years) were treated with RIC allogeneic HCT using MUDs for 7 of the 9 patients and sibling donors for 2 patients. By the Lille classification, 4 patients were characterized as having high risk, 4 as having intermediate risk, and 1 as having low risk. The RIC regimen consisted of fludarabine and a single dose of total body irradiation for the first patient and fludarabine/melphalan for the remaining 8 patients. Granulocyte colony-stimulating factor-primed peripheral blood stem cells (PBSCs) were used for all but 1 patient who received a total of 3 products because of graft failure, of which 2 were bone marrow cells and the third was PBSCs. Prophylaxis against graft-versus-host disease consisted of cyclosporin/mycophenolate with or without methotrexate. Seven patients were successfully engrafted with white blood cells, with an absolute neutrophil count > or =500 by a median of day +15 (range, 10-21 days). At the time of final fluorescence in situ hybridization and/or short tandem repeat analysis, 8 of 9 patients were chimeric, with 96%-100% donor cells and/or DNA. Five of the 9 patients were alive at the time of final contact, with a median follow-up of 32.2 months for the living patients. Overall survival probability at 1 year was 55.6% (95% confidence interval, 31.3%-77.4%). These results suggest that RIC MUD HCT using PBSCs can be an effective treatment for older patients with MF.

Aged↗

Myelofibrosis with myeloid metaplasia: disease overview and non-transplant treatment options.

Myelofibrosis with myeloid metaplasia (MMM) is currently classified as a classic (i.e. not yet molecularly defined) myeloproliferative disorder (MPD), along with essential thrombocythemia (ET) and polycythemia vera (PV). All three MPDs represent stem-cell-derived clonal myeloproliferation that, in the case of MMM, is accompanied by an intense bone marrow stromal reaction that includes collagen fibrosis, osteosclerosis, and angiogenesis. To date, both the molecular basis of the primary clonal process and the pathogenetic mechanisms that underlie the secondary histological changes remain elusive. Clinically, MMM is characterized by anemia, multi-organ extramedullary hematopoiesis that often involves the spleen and liver, constitutional symptoms, and premature death from either leukemic transformation or other disease complications. Current diagnosis is based on characteristic but not diagnostic bone marrow histological features. Modern therapy remains palliative but allogeneic stem cell transplantation might be curative to a selected group of patients. This chapter reviews both the old and the new therapy with regard to non-transplant treatment options for MMM.

Combined Modality Therapy↗

Relationship among densitometry, bone histomorphometry, and histologic stage in idiopathic myelofibrosis.

Idiopathic myelofibrosis (IMF) induces dramatic changes in bone. Bone remodeling and densitometric alterations in a series of nine patients with IMF and their relationship with the histologic stage of the disease were assessed. Patients were included at diagnosis and a bone marrow biopsy, dual-energy X-ray absorptiometry, and transiliac bone biopsy for histomorphometric analysis were performed. Five cases were classified as IMF histologic stage 1, one as stage 2, and three as stage 3. Compared with 40 age- and sex-matched controls, the following histomorphometric parameters were significantly higher in our patients: bone volume (BV/TV), osteoblast surface (Ob.S/BS), eroded surface (ES/BS), osteoclast surface (Oc.S/BS), osteoclast number (N.Oc/TA), mineralizing surface (MS/BS), reversal period (Rv.P), and remodeling period (Rm.P). Mineral apposition rate (MAR) and erosion depth (E.Depth) were significantly decreased (P < 0.05 for all comparisons). Bone mineral density (BMD) measurements showed high values for patient age and sex both at femur neck (Z score range +0.19 to +7) and total femur (Z score range -0.09 to +6.48). When densitometric values were analyzed according to IMF histologic stage, patients in stages 1 and 2 had significantly lower BMD values than to those in stage 3 (P = 0.024). In conclusion, patients with IMF present a characteristic bone histomorphometric pattern with increased bone volume and bone cells but low apposition and decreased erosion depth, suggesting a positive balance in bone remodeling units. This balance would produce the increase in bone mass observed in this disease. Given the increase in BMD observed with more advanced stages of IMF, this noninvasive method could be useful tool for assessing IMF progression.

Biomechanical Phenomena↗

Insertion (4;11)(q27;q24q21) in a patient with essential thrombocythemia with progression to myelofibrosis.

We report a case of essential thrombocythemia (ET) in a 39-year-old woman who developed myelofibrosis at follow-up. The cytogenetic and fluorescence in situ hybridization analyses revealed a pathologic clone with the following previously unreported karyotype: 46,XX,ins(4;11)(q27;q24q21). We cannot conclude that the presence of this inverted insertion was associated with the overproduction of platelets, but documentation of more cases with chromosomal abnormalities and ET should lead to identifying different candidate genes involved in the neoplastic growth.

Adult↗

Activating mutation in the tyrosine kinase JAK2 in polycythemia vera, essential thrombocythemia, and myeloid metaplasia with myelofibrosis.

Polycythemia vera (PV), essential thrombocythemia (ET), and myeloid metaplasia with myelofibrosis (MMM) are clonal disorders arising from hematopoietic progenitors. An internet-based protocol was used to collect clinical information and biological specimens from patients with these diseases. High-throughput DNA resequencing identified a recurrent somatic missense mutation JAK2V617F in granulocyte DNA samples of 121 of 164 PV patients, of which 41 had homozygous and 80 had heterozygous mutations. Molecular and cytogenetic analyses demonstrated that homozygous mutations were due to duplication of the mutant allele. JAK2V617F was also identified in granulocyte DNA samples from 37 of 115 ET and 16 of 46 MMM patients, but was not observed in 269 normal individuals. In vitro analysis demonstrated that JAK2V617F is a constitutively active tyrosine kinase.

Adult↗

Methylation analysis of the cell cycle control genes in myelofibrosis with myeloid metaplasia.

Promoter hypermethylation represents a primary mechanism in the inactivation of tumor suppressor genes during tumorigenesis. We analyzed the promoter methylation status of eight tumor-associated genes (p14 ARF, p15 INK4B, p16 INK4A, Rb, hMLH1, hMSH2, APC, and DAPK) in 30 patients with myelofibrosis with myeloid metaplasia (MMM) by methylation specific PCR. The study showed no hypermethylation of the promoters of p16(INK4A), Rb, hMLH1, hMSH2, APC, and DAPK genes. The p14 ARF, p15 INK4B promoters were hypermethylated in only one patient each. This study indicates that, although methylation of these genes is important in other cancers, it is rare in MMM and causation of this disease should be focused elsewhere.

Adult↗

JAK2(V617F) and leukemic transformation in myelofibrosis with myeloid metaplasia.

Amongst 42 consecutive patients with leukemic transformation (LT) from myelofibrosis with myeloid metaplasia (MMM) 72% carried the JAK2(V617F) mutation. The mutation was observed at expected frequencies in all subtypes of MMM and acute myeloid leukemia. Although the patients with the mutation were younger and had a shorter interval to LT there was no difference in survival. Additionally, both the lack of mutation status progression in serial analysis (available in nine patients) and the low frequency of patients with high mutated allele burden suggest that LT arising from MMM is probably not dependent on changes in JAK2(V617F) mutation status.

Adult↗

[Cytogenetics and molecular genetics in myelofibrosis with myeloid metaplasia and polycythemia vera].

Myelofibrosis with myeloid metaplasia (MMM) is a rare myeloproliferative disorder (MPD) characterized by clonal proliferation of hematopoietic progenitors. 40-50% of karyotypes on blood (or more rarely on bone marrow) revealed at least one abnormality: 30% at diagnosis and 90% in blastic transformation phase. A minority of patients with newly diagnosed polycythemia vera (PV) presented chromosomal abnormalities in their myeloid cells. The most frequent visible alteration in MMM and PV is a 20q deletion, also characterized in other MPDs and myeloid malignancies. Among other chromosomal changes, deletion 13q is more common in MMM than in other MPDs, trisomy 9 and 9p alterations appear more frequent in PV. Cytogenetic studies have disclosed cryptic anomalies and pointed out the high frequency of 9p alterations. JAK2 (V617F) mutation was found in almost all PV patients and near half of MMM patients. This molecular abnormality takes an increased importance in the knowledge of the physiopathology of MPDs, particularly in PV and also in prognosis of MMM patients.

Aneuploidy↗

Current diagnostic criteria for the chronic myeloproliferative disorders (MPD) essential thrombocythemia (ET), polycythemia vera (PV) and chronic idiopathic myelofibrosis (CIMF).

The clinical criteria for the diagnosis of essential thrombocythemia (ET) according to the polycythemia vera study group (PVSG) do not distinguish between ET and thrombocythemia associated with early stage PV and prefibrotic chronic idiopathic myelofibrosis (CIMF). The clinical criteria of the PVSG for the diagnosis of polycythemia vera (PV) only detects advanced stage of PV with increased red cell mass. The bone marrow criteria of the World Health Organization (WHO) are defined by pathologists to explicitly define the pathological criteria for the diagnostic differentiation of ET, PV, and prefibrotic and fibrotic CIMF. As the clinical PVSG and the pathological WHO criteria show significant shortcomings, an updated set of European Clinical and Pathological (ECP) criteria combined with currently available biological and molecular markers are proposed to much better distinct true ET from early PV mimicking ET, to distinguish ET from thrombocythemia associated with prefibrotic CIMF, and to define the various clinical and pathological stages of PV and CIMF that has important therapeutic and prognostic implications. Comparing the finding of clustered giant abnormal megakaryocytes in a representative bone marrow as a diagnostic clue to MPD, the sensitivity for the diagnosis of MPD associated with splanchnic vein thrombosis was 63% for increased red cell mass, 52% for low serum EPO level, 72% for EEC, and 74% for splenomegaly indicating the superiority of bone marrow histopathology to detect masked early and overt MPD in this setting. The majority of PV and about half of the ET patients have spontaneous EEC, low serum EPO levels and PRV-1 over-expression and are JAK2 V617F positive. The positive predictive value for the diagnosis of PV of spontaneous growth of endogenous erythroid colonies (EEC) of peripheral blood (PB) and bone marrow (BM) cells is about 80-85% when either PB or BM EEC assays, and up to 94% when BM and PB EEC assays were performed. The diagnostic impact of low serum EPO levels (ELISA assay) in a large study of 186 patients below the normal range (<3.3 IU/l) had a sensitivity specificity and positive predictive value of 87%, 97% and 97.8%, respectively, for the diagnosis of PV. There is a significant overlap of serum EPO levels in PV versus control and controls versus SE. The specificity of a JAK2 V617F PCR test for the diagnosis of MPD is high (near 100%), but only half of ET and MF (50%) and the majority of PV (up to 97%) are JAK2 V617F positive. The use of biological markers including JAK2 V617 PCR test, serum EPO, PRV-1, EEC, leukocyte alkaline phosphatase score and peripheral blood parameters combined with bone marrow histopathology has a high sensitivity and specificity (almost 100%) to diagnose the early and overt stages of ET, PV and CIMF in JAK2 V617F positive and negative MPDs.

Amino Acid Substitution↗

Chronic idiopathic myelofibrosis (CIMF) resulting from a unique 3;9 translocation disrupting the janus kinase 2 (JAK2) gene.

We report a case of t(3;9)(q21;p24) in a patient with chronic idiopathic myelofibrosis (CIMF), a chronic myeloproliferative disorder (CMPD), initially detected by G-banding and fluorescent in situ hybridization (FISH) in an unstimulated culture of peripheral blood. Subsequent cytogenetic studies of bone marrow aspirates showed the presence and persistence of the same translocation. No additional cytogenetic abnormalities were found. This appears to be a unique translocation that has not been previously reported in the English literature, although both breakpoints, 3q21 and 9p24, are well known cancer-related breakpoints. The former is the mapped location of the ribophorin 1 (RPN1) gene, whereas the latter is the mapped location of the janus kinase 2 (JAK2) gene. This raises the possibility that disruption of one or both loci at the breakpoints of the presently described structural chromosomal rearrangement may be the primary event leading to the initiation and development of the hematopoietic disorder in this patient. It is not unreasonable to hypothesize that the juxtaposition of the RPN1 gene on 3q21 with the JAK2 gene on 9p24 leads to enhanced JAK2 activity. Additional studies will be needed to provide further support for or to disprove this hypothesis. To the best of our knowledge, this is the first reported case of CIMF associated with a reciprocal 3;9 translocation with the 3q21 and 9p24 breakpoints. The elucidation of the mechanism of leukemogenesis in CIMF may one day lead to successful targeted therapy in this hematopoietic disorder. It may also shed additional light on the diagnosis, prognosis and treatment of certain other cancers with similar genetic etiologies.

Chromosome Banding↗

Bone marrow in polycythemia vera, chronic myelocytic leukemia, and myelofibrosis has an increased vascularity.

Several studies have emphasized the significance of neoangiogenesis for tumor growth and progression, but few have focused on malignant hematological disorders. We studied vascular density and architecture in bone marrow samples of patients with chronic myeloproliferative disease (MPD). Vascular structures were immunostained (for von Willebrand factor/FVIII-RAG, CD 31/PECAM or Ulex europeus I for vessels and for vascular endothelial growth factor, VEGF) in samples from patients with polycythemia vera (PV) (n = 7), chronic myelocytic leukemia (CML) (n = 9), and myelofibrosis (MF) (n = 6) when diagnosed and were compared with normal bone marrow specimens (n = 9). We observed that the mean (+/- SD) vessel count per high-power microscopy field (HPF) was 5.3 (+/- 2.1) in normal bone marrow, 5.9 (+/- 2.1) in PV, 10.8 (+/- 3.2) in CML, and 14.4 (+/- 5.5) in MF (P < 0.001 for CMP and MF versus controls). Confocal microscopy, including three-dimensional reconstructions of the blood vessel architecture, confirmed this increased vessel density and revealed tortuous vessel architecture and increased branching in the MPD, particularly in CML and MF. Furthermore, the number of VEGF-positive bone marrow cells was increased in CML and, particularly, in MF. Numbers of VEGF-positive cells and vessels per HPF correlated significantly (r = 0.41; P = 0. 037). Thus the myeloproliferative diseases PV, CML, and MF exhibit neoangiogenesis that is related to diagnosis.

Aged↗

Myelofibrosis in children with chronic renal insufficiency.

During investigation of splenomegaly in a boy with chronic renal failure and osteodystrophy, bone marrow aspirates resulted in "dry taps," whereas biopsied material provided evidence that the marrow had been replaced by fibrous tissue. In a study of six other children with chronic renal failure, similar changes were observed. These findings suggest that the anemia of chronic renal failure may in part be a result of myelofibrosis, and the resulting reduction of functional bone marrow may limit the tolerance to immunosuppressive agents in patients who undergo renal transplantation.

Adolescent↗

Idiopathic myelofibrosis with myeloid metaplasia involving the renal pelves, ureters and bladder.

Myeloid metaplasia associated with idiopathic myelofibrosis most commonly involves the reticuloendothelial organs, such as the spleen, liver and retroperitoneal lymph nodes. We report on a patient with myeloid metaplasia (extramedullary hematopoiesis) of the renal pelves, ureters and bladder. The pathogenesis, clinical characteristics, treatment and prognosis of this condition are discussed.

Adult↗

Granulocytic sarcoma of megakaryoblastic differentiation complicating chronic idiopathic myelofibrosis.

We report the development of soft tissue granulocytic sarcoma with megakaryoblastic differentiation in a patient with chronic idiopathic myelofibrosis, which has hitherto been undescribed. Although an artifactual signet ring appearance of the blasts was found in the formalin-fixed tissue and caused diagnostic problems, the histological appearance on B-5 fixed material and immunophenotyping confirmed the diagnosis. Cytogenetic analysis showed 47,XY,+der(1)del(1)(?p13) at initial presentation and 47,XY,del(1)(?13),+der(1)del(1)(?p13) at the time of soft tissue blastic transformation, indicating that partial trisomy 1 might be of pathogenetic significance.

Adipose Tissue↗

Safety and efficacy of splenic irradiation in the treatment of patients with idiopathic myelofibrosis: a report on 15 patients.

Splenic irradiation in idiopathic myelofibrosis (IMF) has often been use d in selected situations when other therapies were unefficient or contraindicated. This could improve quality of life of patients, but literature remains rare in this field. We have assessed the impact of splenic irradiation in 15 patients with IMF. All of them were no longer responsive to usual treatments, and they presented at least one of the following features: constitutional symptoms, splenic pain, large splenic size, and anemia requiring >2 units of red blood cell transfusion per month. The planned schedule of radiotherapy consisted in daily fractions of 0.4-1 Gy. The median dose of radiotherapy per treatment was 9.8 Gy (range, 0.6-30.5). The overall response rate was 59% with a median duration of 10 months (range, 1-19). Splenic irradiation was more effective on constitutional symptoms, splenic pain, and spleen size. The best responses were noted when full doses of radiotherapy could be delivered, and when patients were previously fewly transfused. Splenic irradiation effectively palliates IMF-related symptoms, and constitute an alternative therapy for patients refractory to usual treatments.

Aged↗

New reciprocal translocation t(6;10) (q27;q11) associated with idiopathic myelofibrosis and eosinophilia.

Idiopathic myelofibrosis (IM), is a chronic myeloproliferative disorder (MPD) characterised by marrow fibrosis, extramedullary haematopoiesis and a leuco-erythroblastic picture of the peripheral blood. Cytogenetic data of IM is scarce: no specific karyotypic anomalies have been yet described. Trisomy 1q, del(13q), del(20q) and trisomy 8, appear in two-thirds of the cases with chromosome aberrations. We report on a 41-year-old patient diagnosed with IM associated with eosinophilia, bearing a novel translocation t(6;10)(q27;q11) as the sole chromosome anomaly. The patient, progressed to AML-M5a within 18 months from diagnosis. Recently new specific chromosomal translocations have been described in chronic MPD. These findings have allowed the classification of new syndromes with defined molecular abnormalities. The case we describe, because of the peculiar clinical features and the association with a previously unreported chromosomal translocation, might be a noteworthy addition.

Adult↗