Spontaneous hemoperitoneum in two patients with myeloproliferative disorders

Spontaneous hemoperitoneum developed in two patients with hitherto undiagnosed myeloproliferative disorders. No other known etiology could be attributed to the two patients described. The report of these two patients suggests that the diagnosis of a myeloproliferative disorder should be considered in the evaluation of patients with spontaneous hemoperitoneum.     

Endogenous megakaryocyte colonies from peripheral blood in precursor cell cultures of patients with myeloproliferative disorders

Megakaryocyte colony formation, as identified by conventional techniques, was observed in precursor cell cultures from peripheral blood in 8 of 20 consecutive patients with diagnosis of myeloproliferative disease (4/11 patients with polycythemia vera, 3/5 with essential thrombocythemia, 1/2 with primary osteomyelofibrosis and 2 with a myeloproliferative syndrome not further assessable), but not in 50 healthy controls (p less than 0.0001). 7 cultures showed spontaneous erythroid colonies, but were negative for megakaryocyte colonies. Megakaryocyte colony formation was independent of added erythropoietin, plasma or human leukocyte-conditioned medium, but was dependent on the presence of accessory cells. The cells in megakaryocyte colonies had the characteristic morphology of megakaryocytes and stained positively with the IIIa/IIb monoclonal anti-platelet antibody. Thus, megakaryocyte colony formation by precursor cells from peripheral blood in the absence of exogenous stimulating factors seems to be a phenomenon specific for myeloproliferative disease. Differential diagnosis of thrombocythemia may be facilitated by demonstration of endogenous megakaryocyte colony formation, which does not occur in secondary disease.     

N-ras and p53 gene mutations in Japanese patients with myeloproliferative disorders

Alterations of the N-ras oncogene and p53 tumor suppressor gene have been demonstrated to play an important role in pathogenesis of hematological malignancies. We simultaneously investigated genetic lesions of both genes in bone marrow cells from 64 Japanese patients with myeloproliferative disorders (MPD), including polycythemia vera (PV), essential thrombocythemia (ET), and idiopathic myelofibrosis (MF), by direct sequencing analysis. No mutations of the N-ras gene were detected in any cases. Two patients, one with chronic neutrophilic leukemia derived from PV and one with acute mylogenous leukemia derived from ET, exhibited three mutations of the p53 gene. Among them, two were missense mutations in exon 5 or 7 and one was a deletion in exon 5. All samples in chronic phase or from MF were devoid of mutations in both genes. These data suggested that disruptions of both genes are extremely rare in MPD in chronic phase and that loss of functions in the p53 gene could be involved in progression of MPD such as PV and ET.     

Increased incidence of another cancer in myeloproliferative neoplasms patients at the time of diagnosis

Several studies have reported an increased incidence of coexistent cancer in patients with myeloproliferative neoplasms (MPN), and myelosuppressive treatment has been speculated to be one of the causes. In this study, we have concentrated on malignancies diagnosed before the MPN diagnosis to eliminate the possible influence of MPN treatment. The patients were recruited from the Swedish and Norwegian cancer registries. One thousand seven hundred and 45 patients from the Swedish MPN Quality Registry and 468 patients from the Norwegian National Cancer Registry were included in this study covering a 3‐yr period. The results show that primary concurrent cancer is higher among patients with MPN compared to the general population. When pooled together, the Swedish and the Norwegian cohort showed increased prevalence of all types of cancer in general compared with the general population, standard prevalence ratio (SPR) of 1.20 (95% CI 1.07–1.34). Significantly high SPRs were reached for skin malignant melanoma [1.89 (95% CI 1.33–2.62)], prostate cancer [1.39 (95% CI 1.11–1.71)], and hematologic cancer [1.49 (95% CI 1.00–2.12)]. In the polycythemia vera group, the risk of having prior malignant melanoma of the skin was significant, with an SPR of 2.20 (95% CI 1.17–3.77). For patients with essential thrombocythemia and primary myelofibrosis, no significant risks were found. Coexisting cancers have a high impact on the treatment strategies of MPN, as it narrows down the treatment options. Chronic inflammation, as a common denominator of MPN with other cancers, can catalyze each other's existence and progression.     

Familial myeloproliferative syndrome

Familial chronic myeloproliferative syndrome (CMS) was observed in five members from two different generations of the same kindred. Diagnoses included agnogenic myeloid metaplasia (case 1), polycythemia vera (case 2), and essential thrombocythemia (cases 3–5). Cases 1–3 were siblings, case 5 was the daughter of case 1, and case 4 was the cousin of cases 1, 3. Age at diagnosis ranged from 28 to 75 years, cases 1 and 3 were male, and the others were female. The diagnosis was made after an episode of cerebral thrombosis in one patient, during a study for headache and dizziness in another, and fortuituously in the three remainders. All patients had splenomegaly and varying degrees of thrombocytosis. The cytogenetic exam was normal in all four cases. A woman patient was treated with interferon during a pregnancy. Fetal growth was retarded, and the newborn showed bone and genital malformations. No environmental leukemogen factor was found. This familial case strengthens Dameshek's theory of a common pathogenesis of CMS and suggests a genetic and hereditary etiology. © 1994 Wiley-Liss, Inc.     

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

Abstract: 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.     

Renovascular hypertension associated with JAK2 V617F positive myeloproliferative neoplasms treated with angioplasty: 2 cases and literature review

Myeloproliferative neoplasms (MPNs) with Janus kinase 2 (JAK2) mutation are associated with a high risk for occlusive vascular diseases. We report 2 cases of renovascular hypertension associated with JAK2 V617F mutation‐positive MPNs and provide a literature review. In Case 1, a 63‐year‐old woman had resistant hypertension, massive proteinuria, and erythrocytosis. Evaluations revealed right renal artery stenosis causing renovascular hypertension and polycythemia vera with JAK2 V617F mutation. Renin‐angiotensin system inhibitors and subsequent angioplasty controlled the blood pressure and the proteinuria resolved. In Case 2, a 74‐year‐old woman had resistant hypertension and thrombocytosis. Evaluations confirmed left renal artery stenosis and essential thrombocythemia with JAK2 V617F. Angioplasty cured the hypertension. A literature review of 18 cases revealed the following as the most common characteristics of MPN‐associated renovascular hypertension: manifests primarily in women; is associated with untreated polycythemia vera and essential thrombocythemia, concomitant leukocytosis, and JAK2 mutation positivity; and is responsive to angioplasty. This report demonstrates that JAK2 mutation‐positive MPNs are a less common but important underlying cause of adult renovascular hypertension.     

CALR,JAK2 and MPL mutation status in Argentinean patients with BCR-ABL1- negative myeloproliferative neoplasms

Objectives: To establish the frequency of JAK2, MPL and CALR mutations in Argentinean patients with BCR-ABL1-negative myeloproliferative neoplasms (MPN) and to compare their clinical and haematological features.

Methods: Mutations of JAK2V617F, JAK2 exon 12, MPL W515L/K and CALR were analysed in 439 Argentinean patients with BCR-ABL1-negative MPN, including 176 polycythemia vera (PV), 214 essential thrombocythemia (ET) and 49 primary myelofibrosis (PMF).

Results: In 94.9% of PV, 85.5% ET and 85.2% PMF, we found mutations in JAK2, MPL or CALR. 74.9% carried JAK2V617F, 12.3% CALR mutations, 2.1% MPL mutations and 10.7% were triple negative. In ET, nine types of CALR mutations were identified, four of which were novel. PMF patients were limited to types 1 and 2, type 2 being more frequent.

Discussion: In ET, patients with CALR mutation were younger and had higher platelet counts than those with JAK2V617F and triple negative. In addition, JAK2V617F patients had high leucocyte and haemoglobin values compared with CALR-mutated and triple-negative patients. In PMF, patients with mutant CALR were associated with higher platelet counts.

Conclusion: Our study underscores the importance of JAK2, MPL and CALR genotyping for accurate diagnosis of patients with BCR-ABL1-negative MPN.     

Bone marrow microvessel density in chronic myeloproliferative disorders: a study of 115 patients with clinicopathological and molecular correlations

Philadelphia-negative chronic myeloproliferative disorders (CMD) include polycythemia vera (PV), essential thrombocythemia (ET) and primary myelofibrosis (PMF). Angiogenesis is critical in the pathogenesis of PMF. We studied angiogenesis in 115 patients with CMD (23 PV, 24 ET, 46 PMF, 12 post-PV and 10 post-ET myelofibrosis) by assessment of microvessel density (MVD) in bone marrow (BM). Kruskall–Wallis analysis of variance showed that patients with PMF had significantly higher values of MVD than those with PV ( P  <   0·001), ET ( P  <   0·001) and controls ( P  <   0·001). Mann–Whitney U -test demonstrated that patients with PMF at the prefibrotic stage had significantly higher MVD values than those with ET ( P  =   0·02). Patients with post-PV myelofibrosis showed significantly higher MVD values than those with PV ( P  <   0·001), as did patients with post-ET myelofibrosis compared with ET ( P  <   0·001). In patients with CMD, the multivariate generalized linear regression model showed that the JAK2 (V617F) mutational burden ( P  =   0·01), serum lactate dehydrogenase level ( P  =   0·003), and anaemia ( P  <   0·001) independently correlated with MVD. In summary, this study indicates that assessment of BM angiogenesis, as measured by MVD, may be a useful additional tool in the histopathological definition of CMD.     

Mobilization of granules in neutrophils from patients with myeloproliferative disorders

Abstract: Neutrophil granule subsets and dynamics were studied in 4 patients with polycythemia vera/myelofibrosis and 2 patients with chronic myelogenous leukemia. Alkaline phosphatase, a marker for the membrane of secretory vesicles (the most readily mobilizable pool of intracellular membranes in neutrophils) was highly elevated in the PV/MF patients and significantly reduced in the CML patients. In spite of this, the amount of secretory vesicles was normal as judged by the content of albumin, and of the membrane protein cytochrome b_{_245} and CD11b, both partially localized in secretory vesicles. Gelatinase granules were present in all patients. The azurophil granules were lighter than normal in both CML patients. SDS-PAGE protein profiles indicated absence of defensins from azurophil granules from 1 CML patient. In addition, a 41–42 kD doublet protein band was absent from 2 PV and 1 CML patient, and reduced in the other CML patient. No difference in mobilization of granules was observed between patient neutrophils and control neutrophils. Also, stimulation with 10 ⁸ mol/l N-formyl-methionyl-leucyl-phenylalanine induced normal increases in intracellular Ca²⁺ in patient neutrophils. These results indicate that stimulus-response coupling leading to granule exocytosis is intact in neutrophils from patients with myeloproliferative disorders.