The reversal of myelofibrosis associated with chronic myelogenous leukemia after allogeneic bone marrow transplantation

A 20-year-old male with chronic myelogenous leukemia (CML) and severe bone marrow fibrosis underwent splenectomy, then ablative chemotherapy, followed by bone marrow transplantation from a histocompatible sister. The myelofibrosis completely resolved. Prompt marrow engraftment and disappearance of Philadelphia chromosome positive cells were documented. Therefore, the presence of marrow fibrosis which frequently accompanies CML is rapidly reversible following high dose chemotherapy and is not indicative of a hostile microenvironment which could preclude marrow transplantation for patients with CML and myelofibrosis.     

T cell-depleted allogeneic bone marrow transplantation in a case of childhood idiopathic myelofibrosis

An 11-year-old boy developed primary myelofibrosis. Nine months after diagnosis he received high-dose chemoradiotherapy followed by T cell-depleted allogeneic bone marrow transplantation as primary therapy. Sixteen months after grafting the patient is well, with reversal of the marrow sclerosis and no evidence of chronic graft-versus-host disease.     

Rapid regression of bone marrow fibrosis after dose-reduced allogeneic stem cell transplantation in patients with primary myelofibrosis

OBJECTIVE: To investigate the effect of a busulfan/fludarabine-based reduced intensity conditioning followed by allogeneic stem cell transplantation on regression of bone marrow fibrosis in patients with myelofibrosis. METHODS: Twenty-four patients (male, n = 16; female, n = 8) with a median age of 52 years (range, 32-63 years) were included. Six patients were transplanted from human leukocyte antigen-identical siblings and 18 patients from matched unrelated donors. Diagnosis was primary myelofibrosis in 18 patients and secondary myelofibrosis in 6 patients; in 4 of them, primary myelofibrosis evolved from polycythemia vera, and in 2 of them from essential thrombocythemia. Using the European Consensus on grading bone marrow fibrosis, all patients had advanced marrow fibrosis MF-2 (n = 13) or MF-3 (n = 11) before allografting According to the Lille Risk Factor Scoring System, patients were classified as low risk (n = 5), intermediate risk (n = 16), or high risk (n = 3). RESULTS: After stem cell transplantation, a complete (MF-0) or nearly complete (MF-1) regression of bone marrow fibrosis was seen in 59% at day +100, in 90% at day +180, and in 100% at day +360. No correlation between occurrence of acute graft-vs-host disease and fibrosis regression on day +180 was observed. CONCLUSION: This study shows that allogeneic stem cell transplantation after reduced-intensity conditioning resulted in rapid regression of bone-marrow fibrosis.     

Bone marrow hypervascularity in patients with myelofibrosis identified by infra-red thermography

Summary Infra-red thermography was used to assess bone marrow vascularity in six patients with myelofibrosis secondary to myeloproliferative disorders (four primary myelofibrosis and two primary proliferative polycythaemia). The technique was evaluated with conventional static and dynamic radio-isotopic imaging and with immunohistochemical staining of bone marrow biopsies. Infra-red thermography identified increased bone marrow blood flow in patients with established myelofibrosis and correlated with dynamic radio-isotopic studies of blood flow and hypervascularity identified by immunohistochemistry. Increased bone marrow blood flow and vascular proliferation was not confined to the central bone marrow but also extended into the peripheral marrow of the long bones. Endothelial cell proliferation may be an initiating event in the pathogenesis of myelofibrosis but evaluation of bone marrow vascularity and blood flow has hitherto relied on invasive and complicated techniques. This study has identified bone marrow hypervascularity in patients with myelofibrosis and shown infra-red thermography to be a simple non-invasive method of assessing vascularity. This non-invasive technique may be used to study disease progression and response to therapeutic regimens in patients with myelofibrosis and to study bone marrow blood flow in other bone marrow disorders.     

Bone marrow hypervascularity in patients with myelofibrosis identified by infra-red thermography.

Infra-red thermography was used to assess bone marrow vascularity in six patients with myelofibrosis secondary to myeloproliferative disorders (four primary myelofibrosis and two primary proliferative polycythaemia). The technique was evaluated with conventional static and dynamic radio-isotopic imaging and with immunohistochemical staining of bone marrow biopsies. Infra-red thermography identified increased bone marrow blood flow in patients with established myelofibrosis and correlated with dynamic radio-isotopic studies of blood flow and hypervascularity identified by immunohistochemistry. Increased bone marrow blood flow and vascular proliferation was not confined to the central bone marrow but also extended into the peripheral marrow of the long bones. Endothelial cell proliferation may be an initiating event in the pathogenesis of myelofibrosis but evaluation of bone marrow vascularity and blood flow has hitherto relied on invasive and complicated techniques. This study has identified bone marrow hypervascularity in patients with myelofibrosis and shown infra-red thermography to be a simple non-invasive method of assessing vascularity. This non-invasive technique may be used to study disease progression and response to therapeutic regimens in patients with myelofibrosis and to study bone marrow blood flow in other bone marrow disorders.     

Tetraspanin CD9 participates in dysmegakaryopoiesis and stromal interactions in primary myelofibrosis

Primary myelofibrosis is characterized by clonal myeloproliferation, dysmegakaryopoiesis, extramedullary hematopoiesis associated with myelofibrosis and altered stroma in the bone marrow and spleen. The expression of CD9, a tetraspanin known to participate in megakaryopoiesis, platelet formation, cell migration and interaction with stroma, is deregulated in patients with primary myelofibrosis and is correlated with stage of myelofibrosis. We investigated whether CD9 participates in the dysmegakaryopoiesis observed in patients and whether it is involved in the altered interplay between megakaryocytes and stromal cells. We found that CD9 expression was modulated during megakaryocyte differentiation in primary myelofibrosis and that cell surface CD9 engagement by antibody ligation improved the dysmegakaryopoiesis by restoring the balance of MAPK and PI3K signaling. When co-cultured on bone marrow mesenchymal stromal cells from patients, megakaryocytes from patients with primary myelofibrosis displayed modified behaviors in terms of adhesion, cell survival and proliferation as compared to megakaryocytes from healthy donors. These modifications were reversed after antibody ligation of cell surface CD9, suggesting the participation of CD9 in the abnormal interplay between primary myelofibrosis megakaryocytes and stroma. Furthermore, silencing of CD9 reduced CXCL12 and CXCR4 expression in primary myelofibrosis megakaryocytes as well as their CXCL12-dependent migration. Collectively, our results indicate that CD9 plays a role in the dysmegakaryopoiesis that occurs in primary myelofibrosis and affects interactions between megakaryocytes and bone marrow stromal cells. These results strengthen the “bad seed in bad soil” hypothesis that we have previously proposed, in which alterations of reciprocal interactions between hematopoietic and stromal cells participate in the pathogenesis of primary myelofibrosis.     

Allogeneic peripheral blood cell transplantation for hypereosinophilic syndrome with myelofibrosis

Patients with hypereosinophilic syndrome (HES) display a very heterogeneous clinical picture ranging from asymptomatic cases to very aggressive forms. We report a 38-year-old woman with progressive HES who developed severe myelofibrosis and was treated by allogeneic stem cell transplantation, using peripheral blood (PBSCT) instead of bone marrow as the source of progenitor cells, after conditioning with cytoxan and busulphan. To the best of our knowledge, this is the first case of HES with myelofibrosis treated with PBSCT. The patient remains alive 8 months post-PBSCT, and bone marrow fibrosis has significantly decreased following transplantation. Bone Marrow Transplantation (2000) 25, 217-218.     

Autoimmune Myelofibrosis and Systemic Lupus Erythematosus in a Middle-Aged Male Presenting Only with Severe Anemia: A case report

Autoimmune myelofibrosis is a distinct clinicopathologic entity that occasionally occurs with autoimmune disorders such as systemic lupus erythematosus (SLE) and rheumatoid arthritis. Most cases of autoimmune myelofibrosis have been reported in female patients with a known history of SLE. We report a case of a middle-aged male patient with an unusual presentation of SLE and autoimmune myelofibrosis who presented only with severe anemia initially and was later diagnosed with SLE and autoimmune myelofibrosis. The patient''s condition improved dramatically after treatment with corticosteroids.SLE and autoimmune myelofibrosis is a rare but potentially devastating condition. Anemia maybe the only presenting symptom in addition to bone marrow fibrosis and careful clinical and laboratory assessment is imperative. Corticosteroids maybe useful and spare patients from bone marrow transplantation.     

Myelofibrosis secondary to hyperparathyroidism.

We report on a young female who had presented with fatigue, bilateral knee pain and gait disturbance. Primary hyperparathyroidism was diagnosed together with splenomegaly and anemia. Bone marrow biopsy revealed myelofibrosis. A parathyroid adenoma was excised during surgical intervention. As early as three months after the operation, hematologic parameters improved along with bone markers without any other intervention. The control bone marrow biopsy demonstrated well marked regression in marrow fibrosis. Her spleen has also gradually decreased in size. These findings indicate that her myelofibrosis was the result of primary hyperparathyroidism. Anemia associated with primary hyperparathyroidism may be due to bone marrow fibrosis.     

Specific marrow ablation before marrow transplantation using an aminophosphonic acid conjugate 166Ho-EDTMP.

166Holmium ethylenediaminetetramethylene phosphonic acid (166Ho-EDTMP) is a short-lived beta-emitting radionuclide complexed to an aminophosphonate ligand that we have investigated in a canine model as a potential agent for specific marrow ablation before marrow transplantation. After intravenous injections, 166Ho-EDTMP distributed principally to bone and after 24 hours the concentrations of 166Ho-EDTMP in bone were more than 200-fold higher than in any other organ. Increasing dosages of 166Ho-EDTMP led to increasingly prolonged and severe myelosuppression, but myeloablation was not achieved. Histologic examination of recovering animals suggested that the spleen may have acted as a reservoir for circulatory hematopoietic precursors. Four splenectomized animals administered 20 to 30 mCi/kg 166Ho-EDTMP without marrow transplantation died with marrow aplasia, while four splenectomized animals administered similar dosages of 166Ho-EDTMP followed by autologous transplantation recovered. The dose-limiting toxicity of 166Ho-EDTMP appeared to be marrow stromal damage resulting in myelofibrosis, which was reversible. These results suggest that 166Ho-EDTMP can be used to specifically ablate marrow function before marrow transplantation.     

Pancytopenia and secondary myelofibrosis could be induced by primary hyperparathyroidism

Hyperparathyroidism may be a precipitating factor important to the development of myelofibrosis: however, there has been only a few reports regarding myelofibrosis secondary to primary hyperparathyroidism. Recently, a rare case of pancytopenia caused by myelofibrosis in a 41-year-old woman who complained of general weakness and arthralgia presented to our clinical service. The patient was diagnosed with primary hyperparathyroidism with pancytopenia. Bone marrow biopsy revealed myelofibrosis. Right parathyroidectomy was performed and a parathyroid adenoma was totally excised. After surgery, the CBC counts and other clinical abnormalities gradually improved without further intervention. We concluded that the pancytopenia was because of bone marrow fibrosis resulting from primary hyperparathyroidism. Therefore, physicians should consider myelofibrosis secondary to primary hyperparathyroidism as a cause of pancytopenia in hypercalcemic patients, even though it is rare.     

Clinical, histopathologic, and genetic features of pediatric primary myelofibrosis--an entity different from adults

Primary myelofibrosis is a chronic myeloproliferative neoplasm characterized by cytopenias, leukoerythroblastosis, extramedullary hematopoiesis, hepatosplenomegaly and bone marrow fibrosis. Primary myelofibrosis is a rare disorder in adults; children are even less commonly affected by this entity, with the largest pediatric case series reporting on three patients. Most literature suggests spontaneous resolution of myelofibrosis without long term complications in the majority of affected children. We describe the clinical, pathologic, and molecular characteristics and outcomes of nineteen children with primary myelofibrosis treated in our center from 1984 to 2011. Most patients had cytopenia significant enough to require supportive therapy. No child developed malignant transformation and only five of the 19 children (26%) had spontaneous resolution of disease. Sequence analyses for JAK2V617F and MPLW515L mutations were performed on bone marrow samples from 17 and six patients, respectively, and the results were negative. In conclusion, analysis of this large series of pediatric patients with primary myelofibrosis demonstrates distinct clinical, hematologic, bone marrow, and molecular features from adult patients.     

Primary myelofibrosis and its targeted therapy

Primary myelofibrosis is a unique entity among BCR-ABL-negative myeloproliferative diseases, manifesting as bone marrow fibrosis and pancytopenia. Considerable evidence indicates that genetic and epigenetic abnormalities can result in defective clonal hematopoietic stem cell proliferation in addition to bone marrow microenvironment alteration. The “bad seeds in bad soil” theory illustrates the orchestrating efforts of hematopoietic stem cells, stromal cells, and their surrounding signaling molecules in myelofibrosis progression and malignancy transformation, though the exact mechanism of myelofibrosis is still not clear. This study reviews current concepts and questions regarding the pathogenesis of primary myelofibrosis and discusses the emerging targeted therapy aimed at restoring normal bone marrow environment and halting bone marrow fibrotic deterioration.     

A model of myelofibrosis and osteosclerosis in mice induced by overexpressing thrombopoietin (mpl ligand): reversal of disease by bone marrow transplantation

We have previously shown that mice induced to overexpress thrombopoietin (TPO) by retroviral-mediated gene transfer into bone marrow (BM) cells develop myelofibrosis and osteosclerosis. It was speculated that these effects were secondary to TPO, resulting from high levels of megakaryocytes and platelets. Also, it was proposed that these mice represent a model for myelofibrosis and osteosclerosis. In this report, we show that levels of both transforming growth factor- beta 1 and platelet-derived growth factor are increased twofold to fivefold in the platelet-poor plasma of TPO overexpressing mice compared with control mice. These data suggest that the increased megakaryocytes produce elevated levels of these cytokines that lead to the pathogenesis of disease. Further, we retransplanted TPO overexpressing mice, at 40 to 42 weeks after primary transplantation, with normal BM cells. After the secondary transplantation, megakaryocytes and platelets returned to normal levels and the myelofibrosis and osteosclerosis were completely corrected. These data extend our initial studies of the effects of overexpression of TPO and show the potential use of this model to explore the underlying cause of myelofibrosis and osteosclerosis and potential treatments for these diseases.     

Childhood monosomy 7 revisited

Monosomy 7 is found in acute myeloid leukaemia (AML) and myelodysplasia and is characteristic of a rare chronic myeloproliferative disease (MPD) of young children. We have seen 16 children with monosomy 7. Their clinical features and response to treatment are discussed. Monosomy 7 diseases appear to have a particularly poor prognosis. The AML is often resistant to treatment and relapse is common. Children with chronic MPD die of bone marrow failure or evolve to AML or myelofibrosis. We have treated these children intensively with combination chemotherapy and allogeneic bone marrow transplantation. Four children with MPD received supportive care and low dose chemotherapy alone. They all died, surviving between 4 months and 4 years. Six children with MPD received intensive chemotherapy: three remitted, one relapsing after 9 months, the others remaining in remission at 18 months and 3 years. One child with MPD has undergone successful BMT and survives 7 1/2 years after presentation. Remission was achieved in three of four cases of AML. They all relapsed within 9 months. Bone marrow transplantation was successful in one child with myelofibrosis. Intensive chemotherapy and early bone marrow transplantation is likely to offer these children their best chance of survival.     

CD146+ bone marrow osteoprogenitors increase in the advanced stages of primary myelofibrosis

CD146⁺ bone marrow stromal cells have been recently recognized as clonogenic osteoprogenitors able to organize a complete hematopoietic microenvironment. In this study we used immunohistochemical analysis to investigate the contribution of CD146⁺ bone marrow osteoprogenitors to the stromal remodeling occurring in the different stages of primary myelofibrosis. We found that CD146⁺ cells sited at the abluminal side of the bone marrow vessels and branching among hematopoietic cells significantly increased in the advanced stages of primary myelofibrosis (p<0.001), paralleling the extent of fibrosis (ρ=0.916, p<0.0001) and the microvascular density (r=0.883, p<0.0001). Coherently with a mural cell function, such cells also displayed smooth-muscle actin expression. Our data providing evidence of CD146⁺ cell involvement in bone marrow stromal changes occurring in primary myelofibrosis are consistent with the capability of these cells to participate in fiber deposition, angiogenesis, and bone formation. They could also represent rationale for new therapies targeting the bone marrow stroma in primary myelofibrosis.     

Primary autoimmune myelofibrosis: definition of a distinct clinicopathologic syndrome

Myelofibrosis is characterized by reticulin fibrosis of the bone marrow with resulting features of myelophthisis. Besides hematopoietic malignancies and other neoplasms involving the bone marrow, myelofibrosis has been described in association with autoimmune disorders, especially systemic lupus erythematosus. We describe the clinicopathologic features of a primary form of autoimmune myelofibrosis (AIMF) in patients who do not have systemic lupus erythematosus or another well-defined autoimmune syndrome. Absence of marked splenomegaly, peripheral blood cytopenias with mild teardrop poikilocytosis and leukoerythroblastosis, bone marrow lymphoid aggregates, and presence of autoantibodies are some of the salient features of primary AIMF. AIMF should especially be differentiated from chronic idiopathic myelofibrosis, a neoplastic myeloproliferative disease. Primary AIMF appears to have an excellent prognosis, with all patients reported in this series responding to a short course of corticosteroid therapy.     

Cytogenetic studies of bone marrow fibroblasts cultured from patients with myelofibrosis and myeloid metaplasia.

Cytogenetic studies of bone marrow fibroblasts and blood cells from peripheral blood or bone marrow were performed in 19 patients with myelofibrosis with myeloid metaplasia (group 1), nine patients with other myeloproliferative syndromes without myelofibrosis (group 2), and 12 patients with anaemia secondary to iron deficiency or chronic inflammatory disease (group 3). Clonal cell populations with abnormal karyotypes were seen in the bone marrow or blood in five of 14 (36%) group 1 patients, one of nine (11%) group 2 patients and none (0%) of the group 3 patients. Abnormal karyotypes of bone marrow fibroblasts were found in three of 16 (19%) of patients of group 1, and in two of nine (22%) and two of 12 (17%) patients each of groups 2 and 3, respectively. Since abnormal karyotypes can be found in bone marrow fibroblasts cultured from normal subjects, and since the abnormalities seen in the bone marrow fibroblasts differed from those found in bone marrow or blood cells, it is suggested that abnormal karyotypes found in bone marrow fibroblasts cultured from patients with primary myelofibrosis do not necessarily reflect neoplasia. The results of this study are compatible with the widely accepted hypothesis that in patients presenting with 'primary' myelofibrosis, the fibrosis is a secondary reactive process.     

Allogeneic bone marrow transplantation for primary myelofibrosis after splenectomy

A 46-year-old woman was given a diagnosis of primary myelofibrosis (PMF) in 1996. Because of the progression of anemia and splenomegaly, she was scheduled for allogeneic bone marrow transplantation (BMT) from an HLA-matched sibling donor in April 1998. Cyclophosphamide and busulfan were used as the conditioning regimen. Before BMT, the patient was treated with hydroxycarbamide, which did not resolve splenomegaly. She then underwent a splenectomy, which was followed by massive portal vein thrombosis without any significant clinical outcome. After BMT, the patient obtained rapid hematologic engraftment. Moreover, the alleviation of marrow fibrosis was confirmed 4 months after BMT. We concluded that allogenic BMT can cure patients with PMF, but that the issue of splenectomy and the indications for BMT need to be evaluated further.