Is hypereosinophilic syndrome a malignant disease?

Concurrent onset of an eosinophilic ulcer of the oral mucosa with peripheral eosinophilia in a human T-cell leukemia virus type I carrier

We present a case of a 46-year-old Japanese woman with an eosinophilic ulcer of the oral mucosa (EUOM), located in the buccal mucosa, who was found by various examinations to be a human T-cell leukemia virus type I (HTLV-1) carrier with peripheral eosinophilia. Her peripheral eosinophilia and EUOM promptly improved in response to oral corticosteroid therapy. EUOM has been described to be possibly associated with trauma, but its etiology has not been fully elucidated to date. In the present case, the presence of peripheral eosinophilia in addition to the EUOM indicated possible influence of certain immune system abnormalities associated with HTLV-1 infection.

Granulocytic sarcoma of the small intestine

Granulocytic sarcoma is an extramedullary tumor of myeloblasts and/or immature myeloid cells, which can develop at any anatomic site and is often a forerunner to the development of acute myelogenous leukemia. Granulocytic sarcoma of the gastrointestinal tract most frequently involves the small intestine and most often presents with abdominal pain and obstruction. Pathologists must consider granulocytic sarcoma in any mass of unknown origin with a diffusely infiltrating population of tumor cells, as the diagnosis is often initially unrecognized, especially in nonleukemic patients. Multiple ancillary modalities are available to assist pathologists in making the correct diagnosis so that appropriate therapy can be initiated.

Molecular classification and pathogenesis of eosinophilic disorders: 2005 update

Use of the term "idiopathic hypereosinophilic syndrome (HES)" has highlighted our basic lack of understanding of the molecular pathophysiology of eosinophilic disorders. However, over the last 10 years, the study of hypereosinophilia has enjoyed a revival. This interest has been rekindled by two factors: (1) the development of increasingly sophisticated molecular biology techniques that have unmasked recurrent genetic abnormalities linked to eosinophilia, and (2) the successful application of targeted therapy with agents such as imatinib to treat eosinophilic diseases. To date, most of these recurrent molecular abnormalities have resulted in constitutively activated fusion tyrosine kinases whose phenotypic consequence is an eosinophilia-associated myeloid disorder. Most notable among these are rearrangements of platelet-derived growth factor receptors alpha and beta (PDGFRalpha, PDGFRbeta), which define a small subset of patients with eosinophilic chronic myeloproliferative disorders (MPDs) and/or overlap myelodysplastic syndrome/MPD syndromes, including chronic myelomonocytic leukemia. Discovery of the cryptic FIP1L1-PDGFRA gene fusion in cytogenetically normal patients with systemic mast cell disease with eosinophilia or idiopathic HES has redefined these diseases as clonal eosinophilias. A growing list of fibroblast growth factor receptor 1 fusion partners has similarly emerged in the 8p11 myeloproliferative syndromes, which are often characterized by elevated eosinophil counts. Herein the focus is on the molecular gains made in these MPD-type eosinophilias, and the classification and clinicopathological issues related to hypereosinophilic syndromes, including the lymphocyte variant. Success in establishing the molecular basis of a group of once seemingly heterogeneous diseases has now the laid the foundation for establishing a semi-molecular classification scheme of eosinophilic disorders.

The role of trisomy 8 in the pathogenesis of chronic eosinophilic leukemia

A case of chronic eosinophilic leukemia (CEL) manifesting as spinal cord compression by an extradural eosinophilic chloroma in a 32-year-old Chinese man was presented, who subsequently developed extramedullary transformation at the skin and then peritoneal cavity. Cytogenetic study of bone marrow cells at diagnosis showed a clonal karyotypic abnormality of trisomy 8 (+8), which on fluorescence in situ hybridization (FISH) was shown to be present in a clone of abnormal eosinophils, hence showing the neoplastic nature of the eosinophilic proliferation. There was another population of abnormal eosinophils that did not show +8. At blastic transformation, all blast cells in ascitic fluid were shown by FISH to harbor +8. These findings suggest that +8 in this case may have arisen from clonal evolution and is not the primary genetic event in leukemogenesis, but +8 most probably imparts a further survival advantage to the clone responsible for subsequent blastic transformation.

Chronic eosinophilic leukemia and hypereosinophilic syndromes. Proposal for classification, literature review, and report of a case with a unique chromosomal abnormality

The idiopathic hypereosinophilic syndromes (HES) are rare hematologic disorders characterized by persistent eosinophilia with organ involvement that encompass a wide spectrum of clinical and hematological disease states. We propose a classification scheme to further delineate these patients, and present a case of a 45-year-old male with persistent eosinophilia, severe tissue and hematologic involvement, and trisomy 15. Although multiple cytogenetic abnormalities have been associated with hypereosinophilic syndromes, this is the first reported case where trisomy 15 is the sole chromosomal abnormality.

Familial eosinophilia maps to the cytokine gene cluster on human chromosomal region 5q31-q33

Familial eosinophilia (FE) is an autosomal dominant disorder characterized by peripheral hypereosinophilia of unidentifiable cause with or without other organ involvement. To localize the gene for FE, we performed a genomewide search in a large U.S. kindred, using 312 different polymorphic markers. Seventeen affected subjects, 28 unaffected bloodline relatives, and 8 spouses were genotyped. The initial linkage results from the genome scan provided evidence for linkage on chromosome 5q31-q33. Additional genotyping of genetic markers located in this specific region demonstrated significant evidence that the FE locus is situated between the chromosome 5q markers D5S642 and D5S816 (multipoint LOD score of 6.49). Notably, this region contains the cytokine gene cluster, which includes three genes-namely, those for interleukin (IL)-3, IL-5, and granulocyte/macrophage colony-stimulating factor (GM-CSF)-whose products play important roles in the development and proliferation of eosinophils. These three cytokine genes were screened for potential disease-specific mutations by resequencing of a subgroup of individuals from the present kindred. No functional sequence polymorphisms were found within the promoter, the exons, or the introns of any of these genes or within the IL-3/GM-CSF enhancer, suggesting that the primary defect in FE is not caused by a mutation in any one of these genes but, rather, is caused by another gene in the area.

Granulocytic sarcoma with translocation (9;11)(p22;q23): two cases

Granulocytic sarcomas are localized deposits of myeloid leukemia cells that may precede or occur concurrently with disseminated disease. In either event, the origins of the cells comprising the malignancy are the same. Published reports of granulocytic sarcomas have described, in the majority of cases, a morphology typical of AML-M2 and the presence of the t(8;21)(q22;q21) typical of that FAB type. In a smaller number of cases, the inv(16)(p13q22) characteristic of AML-M4 has been recorded in cells with a myelomonocytic appearance. We report two patients with granulocytic sarcomas showing monocytic morphology in which the malignant cells showed t(9;11)(p22;q23) typical of AML-M5. This abnormality is seen in up to 7% of childhood AML, but has not previously been reported in granulocytic sarcoma. The detection of this cytogenetic abnormality facilitated the precise characterization of the malignant cells and selection of the most appropriate therapy, emphasizing the value of cytogenetic analysis in cases of granulocytic sarcoma.

Chronic myeloid leukemia associated hypereosinophilic syndrome with a clonal t(4;7)(q11;q32)

Patients with chronic myeloid leukemia (CML) show the Philadelphia (Ph) translocation in more than 95% of the cases. The remaining cases, without the cytogenetic or molecular equivalent of the BCR-ABL rearrangement, are "Philadelphia negative" and may have alternate chromosomal aberrations. Ph negative CML patients are known to have a poor prognosis. We report on a young patient with a hypereosinophilic syndrome in the presence of a clonal translocation t(4;7) with a peripheral leukocytosis, a severe thrombocytopenia, and anemia at first presentation, who developed bone marrow changes typical of CML. Bone marrow function and hypereosinophilia improved only partially and temporarily under therapy. The patient died 10 months after diagnosis of diffuse leukemic embolism and organ infiltration resulting in paraplegia. The case demonstrates that beside "idiopathic" hypereosinophilic syndromes (HES), a proportion of such patients suffer from eosinophilic leukemias. In these cases, karyotype analysis may help to distinguish these states by the identification of clonal chromosomal abnormalities. A karyotype anomaly hitherto not reported can be added to the list of aberrations in hypereosinophilic states associated with myeloproliferative processes.

Biological characteristics of chronic eosinophilic leukemia cells with a t(2;5)(p23;q35) translocation

We studied the biological features of eosinophils in a patient with chronic eosinophilic leukemia and a unique t(2:5)(p23;q35) translocation. Microscopic and cytochemical studies revealed no particular abnormalities, although more than 90% of the peripheral eosinophils had a density lighter than 1.080 g/ml. Clonogenic assay disclosed that myeloid progenitor cells possessed the translocation, although in vitro eosinophilopoiesis seemed normal, and there were also hematopoietic cells with a normal karyotype. In a surface marker study, EG1 was positive on 34.0% of the eosinophils, while EG2 positivity was only 0.5%. Eosinophilopoietic growth factors and adhesion molecules were virtually absent with the exception of GM-CSF and CD11b. Functional studies showed that chemotaxis for C5a was normal, although that for IL-2 or FMLP was attenuated. In addition, leukotriene C4 production was decreased while O2- production was intact. These findings indicated that our patient's eosinophils were not in an activated state despite their extreme hypodensity, and suggested that the leukemic eosinophils had slight defects of cellular function. These characteristics may have saved the patient from the multiple organ damage which occurs in typical hypereosinophilic syndrome.

Myelofibrosis in a child suffering from a hypereosinophilic syndrome with trisomy 8: response to corticotherapy

The idiopathic hypereosinophilic syndrome (IHS) is extremely rare in childhood and relationships of this syndrome with myeloproliferative diseases are controversial. We reported the observation of a 7-year-old girl suffering from an IHS with myelofibrosis. A clonal cytogenetic abnormality, trisomy 8, was detected in the bone marrow cells of this child. This is the decisive proof of a myeloproliferative disorder. IHS with myelofibrosis is usually considered as unresponsive to corticotherapy. In our case, corticotherapy resulted in a rapid, complete, and lasting disappearance of myelofibrosis. Complete remission of the disease, however, was not achieved and the trisomy 8 persisted after treatment.

Episodic angioedema with eosinophilia

A 40-year-old woman had monthly episodes of angioedema, eruption of pruritic papules and plaques and fever. During acute episodes white blood cell counts increased to 31,000/mm3 with 75% eosinophils, body weight increased to 10% of baseline weight, and urine excretion decreased to 40 ml/24 hours. No evidence was found for cardiac or other visceral organ involvement. Extensive diagnostic evaluations revealed no evidence for parasitic infestation, connective tissue disease, or neoplastic disorders. Results of immunologic studies revealed increased serum IgM and IgE levels and showed elevated levels of circulating activated T-helper cells. Biopsy specimens of lesional skin showed dermal infiltration of lymphocytes and eosinophils with deposition of eosinophil granule major basic protein in the extracellular matrix within the dermis. Immunophenotyping of the dermal infiltrate with monoclonal antibodies revealed the predominance of T-helper cells, many of them expressing the human leukocyte antigen (HLA)-DR, suggesting that angioedema with eosinophilia may be a T-helper cell-mediated disease.

Eosinophilia associated with adult T-cell leukemia/lymphoma

Eosinophilia is associated with a number of disorders including malignancies. A patient is described who had eosinophilia associated with adult T-cell leukemia/lymphoma (ATL) induced by human T-lymphotropic virus type I (HTLV-I). Both tissue and peripheral blood eosinophilia and high titers of HTLV-I antibody were present. The eosinophilia was most likely caused by the malignant cells producing one or more lymphokines. The patient has achieved a durable complete remission from combination chemotherapy. Because durable remissions in ATL are rare with any known therapy and eosinophilia has not previously been associated with ATL, it is possible that the tumor in this patient was derived from a T-cell subset not usually transformed by HTLV-I. ATL is another malignancy now known to cause eosinophilia.

Evidence for the clonal nature of hypereosinophilic syndrome

Hypereosinophilic syndrome (HES) is a disease process of unknown pathogenesis. Although some cases are believed to be primary hematologic malignancies, this issue remains unsolved. We present a case of HES in whom we have observed a clone of cytogenetically abnormal cells in the bone marrow in parallel with a clinical picture of a hematologic disorder characterized by progressive proliferation and organ infiltration by eosinophils. The cytogenetic abnormality 46,XY,t(7;12)(q11;p11) is previously unreported. Our case, plus other evidence present in the literature, supports the concept that HES is a hematologic malignant neoplasia.

Hypereosinophilia syndrome with pneumonia in acute lymphoblastic leukaemia

Eosinophilic pneumonia in association with acute lymphoblastic leukaemia (ALL) is very rare. A teenage boy is described with eosinophilic pneumonia which preceded by several months the onset of ALL. Prior to establishment of the diagnosis he had been treated with corticosteroids with a transient response only. This delayed his final diagnosis until there were haematologic features of leukaemia. The leukaemic blasts were cALLA (CD10) positive and had a normal chromosome number with no translocations on banding studies. The pneumonia remitted rapidly when his leukaemia responded to chemotherapy.

Abnormalities of chromosome 12p13 and malignant proliferation of eosinophils: a nonrandom association

Four patients representing a spectrum of haematological malignancies are reported. Two patients had Philadelphia chromosome negative myeloproliferative disorders, one had acute lymphoblastic leukaemia and one had eosinophilic leukaemia. In each case eosinophilia was present and demonstrated to be part of the malignancy by the association of clonally abnormal metaphases with eosinophil granules. Abnormalities involving the short arm of chromosome 12 (12p13) were a constant feature in all four cases and therefore a nonrandom association between this chromosome region and malignant eosinophil proliferation is proposed.