Polycythaemia vera-transformation to myelofibrosis and subsequent reversal

Revisiting Circulating Extracellular Matrix Fragments as Disease Markers in Myelofibrosis and Related Neoplasms

Philadelphia chromosome-negative chronic myeloproliferative neoplasms (MPNs) arise due to acquired somatic driver mutations in stem cells and develop over 10-30 years from the earliest cancer stages (essential thrombocythemia, polycythemia vera) towards the advanced myelofibrosis stage with bone marrow failure. The JAK2V617F mutation is the most prevalent driver mutation. Chronic inflammation is considered to be a major pathogenetic player, both as a trigger of MPN development and as a driver of disease progression. Chronic inflammation in MPNs is characterized by persistent connective tissue remodeling, which leads to organ dysfunction and ultimately, organ failure, due to excessive accumulation of extracellular matrix (ECM). Considering that MPNs are acquired clonal stem cell diseases developing in an inflammatory microenvironment in which the hematopoietic cell populations are progressively replaced by stromal proliferation-"a wound that never heals"-we herein aim to provide a comprehensive review of previous promising research in the field of circulating ECM fragments in the diagnosis, treatment and monitoring of MPNs. We address the rationales and highlight new perspectives for the use of circulating ECM protein fragments as biologically plausible, noninvasive disease markers in the management of MPNs.

Progression of primary myelofibrosis to polycythemia vera: A case report

RATIONALE

This case report describes the progression of primary myelofibrosis (PMF) to polycythemia vera (PV), and discuss its potential mechanisms.

PATIENT CONCERNS

The patient was admitted because of abdominal discomfort and enlarged spleen for 19 months.

DIAGNOSIS

A case of PMF progressed to PV was retrospectively analyzed. There were 19 months between the diagnosis of PMF and PV. The JAK2 V617F mutation was positive before and after the diagnosis of PV; however, new chromosomal abnormalities were detected during the progression.

INTERVENTIONS

For treatment of PMF, the danazol, calcitriol, and thalidomide were given. Then, the use of thalidomide and calcitriol was stopped, and hydroxyurea was started. For treatment of PV, interferon treatment was given, whereas hydroxyurea was continued.

OUTCOMES

After 30 months of the progression (at the recent follow-up), this patient had no obvious symptoms or thrombosis.

LESSONS

PMF rarely progresses to PV, however, the progression will significantly improve the quality of life and prognosis.

Myelofibrosis in chronic myeloproliferative disorders. Incidence among subtypes according to the Hannover Classification

The distribution and the development of fibrosis were evaluated from bone marrow biopsies of patients with chronic myeloproliferative disorders (CMPD), regarding two groups of patients: (1) 564 with follow-up biopsies over a period of up to twelve years observation time, and (2) 1.787 diagnostic bone marrow biopsies from CMPD patients. Fibrosis was divided into three grades of fiber increase: early myelosclerosis, myelofibrosis, and advanced myelofibrosis. The first group of sequential BMB showed a significant progress to myelofibrosis in so-called "Chronic Megakaryocytic-Granulocytic Myelosis"--CMGM-, which corresponds to Agnogenic Myeloid Metaplasia-AMM-in 72.4% (21/29 patients), as well as in CML with megakaryocytic increase-CML.MI-in 39.2% (20/51). In the second group of diagnostic biopsies, only 30% of CMGM cases showed no fibrosis. In P. vera, 16.2% (18/111) developed myelofibrosis up to twelve years later. This figure was 4.3% (2/46) in Primary Thrombocythemia. Increase of megakaryocytes in CML indicates a high risk for developing fibrosis, combined with reduced life expectancy.

Myelofibrosis: a review of clinical and pathologic features and treatment

The purpose of this review is to discuss and clarify the current understanding of the pathogenesis, clinical manifestations, and treatment of MF. MF may be either a primary or secondary disorder. It is characterized by an increased deposition of bone marrow collagen, fibronectin, and laminin. Present evidence indicates that MF may be mediated by platelet or megakaryocyte growth factors, decreased prostaglandin mediated stem cell inhibition, immune complex deposition, and both fibroblast and endothelial cell proliferation. Recently acute MF has been recognized to be identical to acute megakaryocytic leukemia. Secondary MF usually responds to appropriate treatment of the underlying disease. Primary MF is usually treated by blood product support, but may be responsive to androgens, splenectomy, splenic irradiation, chemotherapy, or bone marrow ablation with marrow reconstitution.

Reversal of bone marrow fibrosis and subsequent development of polycythemia in patients with myeloproliferative disorders

Bone marrow fibrosis is a characteristic finding in agnogenic myeloid metaplasia and in the spent phase of polycythemia vera. It is commonly believed that the reticulin deposition is irreversible. However, we report four patients who demonstrated clinical and laboratory evidence of transition from myelofibrosis to polycythemia. The transition was documented by improvement in the hemoglobin concentration and by determination of the Cr51 red blood cell mass, accompanied by a resolution of the fibrosis on serial bone marrow biopsies. Two of the patients had been treated with alkylating agents and splenectomy, one with myelosuppressive therapy without splenectomy, and one with splenectomy alone. These findings indicate that bone marrow fibrosis in the chronic myeloproliferative disorders is not always an irreversible phenomenon. Pathogenetic implications will be discussed.

Development of polycythaemia vera in a patient with myelofibrosis

In March 1981, a 53-year-old man presented with itching and was diagnosed as having myelofibrosis. There was gradual enlargement of the spleen over the following 5 yr. His spleen had to be removed in February 1986 because of physical discomfort. 3 months post-splenectomy he became polycythaemic. Bone marrow examination was consistent with severe myelofibrosis. It was possible to demonstrate erythropoietin-independent BFU-E from peripheral blood, and ferrokinetic studies showed that erythropoiesis was localised to the liver with little bone marrow activity. Thus, despite severe marrow fibrosis, liver erythropoiesis was now polycythaemic, suggesting the coexistence of myelofibrosis and polycythaemia vera.

Restoration of active haemopoiesis in a patient with myelofibrosis and subsequent termination in acute myeloblastic leukaemia: case report and review of the literature

A patient with polycythaemia vera developed typical myelofibrosis after 15 yr. After a further 8 months, during which time she was pancytopenic and transfusion-dependent, a slow spontaneous recovery in haemopoiesis occurred and the full blood count became normal. 6 months later pancytopenia recurred and soon afterwards the patient developed acute myeloblastic leukaemia from which she died. The evolution of bone marrow morphology and isotopic studies. Only 2 previous reports of this kind of transformation exist in the literature, although restoration of normal or polycythaemic haemopoiesis has been reported in 8 patients with myelofibrosis. It is likely that these transformations occur because of alterations in stem cell behaviour rather than as a result of therapy.

Type III aminoterminal propeptide of procollagen in some haematological malignancies

Marrow fibrosis is involved in some haematological malignancies. Either because of sampling errors, variations of focal distribution of fibrosis or the discomfort for patients of bone biopsies, conventional histology appears to be unsuitable for the follow-up of myelofibrosis. During collagen synthesis by marrow fibroblasts, the aminoterminal propeptide is removed from procollagen III and released in the serum. Thus, a sensitive radioimmunoassay of type III aminoterminal propeptide of procollagen (PC III) has been tested in myeloproliferative and lymphoproliferative disorders with a marked bone marrow fibrosis. In polycythaemia vera, PC III level was significantly increased as compared to controls and was related to marrow fibrosis of grade I. The more increased PC III values were observed in spent polycythaemia cases initially treated by phlebotomy alone. Follow-up showed a transformation into myeloid metaplasia. In contrast, PC III remained stable in patients treated with radiophosphorus 32P or hydroxyurea who did not transform. In myeloid metaplasia, results of PC III were significantly higher than in controls or polycythaemia vera cases. Myelofibrosis of recent onset (less than 2 years) gave higher values than chronic myelofibrosis. Increased PC III values were also emphasized in chronic myelocytic leukaemia, and in a few cases of refractory anaemia with excess of blasts, hairy cell leukaemia and chronic lymphocytic leukaemia.

Chorea with transitional myeloproliferative disease

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Polycythaemia following splenectomy in myelofibrosis with myeloid metaplasia. A reorganization of erythropoiesis

3 patients with myelofibrosis with myeloid metaplasia were splenectomized because of anaemia and disturbing splenomegaly. In the course of the 6 months following splenectomy, a polycythaemia developed. Erythrokinetic studies demonstrated that in all cases a reduction in plasma volume and an increase in red cell volume was obtained. Total erythropoiesis decreased along with normalization of ineffective erythropoiesis and peripheral haemolysis. The reappearance of an erythropoietic activity measured over the sacrum was a constant finding, while in 1 patient, a depression of activity over the liver was observed. The new distribution and organization of erythropoiesis in the splenectomized patients is hypothesized as being due to the removal of the influence of an enlarged spleen on erythropoietic organs.

The 'spent' phase of polycythaemia vera: hypersplenism in the absence of myelofibrosis

A clinical phase (spent phase) in the course of polycythaemia vera (PV) cases is described as enlargement of the spleen in spite of treatment, frequent cytopenia of one or several lines, persistent red cell hypervolaemia with considerable increase of plasma volume, persistence of myeloid hyperplasia with no collagen myelofibrosis or osteomyelosclerosis, absence of hepatosplenic erythroblastic metaplasia, as shown by radio-iron kinetics and/or 111In-transferrin scintigraphy. The frequency of this phase was 5% in a study where it was not systematically sought, but it could in fact be greater. Its occurrence is not related to the clinical and biological parameters of PV. On the other hand, it is significantly more frequent and earlier in patients treated by phlebotomies than in those treated by myelosuppression (32P). In four of the 12 cases, this phase was rapidly followed by an acute leukaemia. In eight cases there was a 1-5 year interval before a myelofibrosis with splenic myeloid metaplasia. This evolution could at this stage be delayed by chemotherapy. The efficacy of splenectomy should be studied.

Transition of myelofibrosis to polycythaemia vera

A case of typical myelofibrosis with a huge spleen is described in a 62-year old man. During the subsequent 2-year follow-up, a clinical picture of polycythaemia vera with pancytosis and disappearance of the marrow fibrosis was observed. The pancytosis necessitated treatment with busulphan and frequent phlebotomies. The transformation was associated with prednisone treatment for a suspected haemolytic state. During this treatment, the spleen no longer became enlarged on clinical palpation, although it was still enlarged at post mortem examination, but much less than 2 years earlier.

Transitional myeloproliferative disorder

Eleven patients have been observed with clinical features of both polycythaemia vera and myelofibrosis. Detailed follow-up and repeated haematological and isotopic investigations, including the assessment of erythropoietic distribution by 52Fe scanning, over a 10 year period, have indicated that patients who initially present with this syndrome may remain in a steady state for several years and that this transitional syndrome does not necessarily imply an active or irreversible transformation into classical myelofibrosis. Therapy with iron, folic acid, alkylating agents, splenectomy or splenic irradiation may reduce the extramedullary component of myeloproliferation and allow occasional patients to revert to more classical polycythaemia vera. Radioactive phosphorus (32P) therapy may be inappropriate in polycythaemic patients with dominant extramedullary erythropoiesis, as this form of therapy has a preferential medullary action and may selectively encourage extramedullary myeloproliferation.