The vagaries of erythroleukaemia

Acute erythroid leukemia (M6): outcome of bone marrow transplantation

Erythroid leukemia is an uncommon form of acute myeloid leukemia (AML) which has previously been associated with a poor prognosis. We present the outcome of 27 patients with AML-M6 (19 de novo and 8 secondary) treated with intensive regimens including bone marrow transplantation (BMT). In the de novo group, median age was 30 years (2-72); 5 cases were under 15 years. Remission rate after induction chemotherapy was 95%. Consolidation in those achieving remission with BMT was 82%. Transplant related mortality was 36%. Median survival for de novo M6 was 2.9 years which was not significantly different to matched controls with AML (non M6). Overall relapse rate was 35%. In contrast, patients with secondary disease had a poor prognosis with lower remission rates (57%) and higher relapse rates (75% of those achieving remission after induction chemotherapy). In our series, the prognosis of patients with AML-M6 was most closely related to age and disease status at presentation (de novo or secondary). The disease is sensitive to AML induction regimens and long-term survival can be achieved with BMT in first complete remission.

The erythroid leukemias: a comparative study of erythroleukemia (FAB M6) and Di Guglielmo disease

Pure erythroid malignancies, such as Di Guglielmo disease (DG), in which the predominant immature elements are proerythroblasts, are excluded from the French-American-British (FAB) classification for acute leukemia and do not fit neatly into any of the categories of myelodysplasia. This retrospective review compares the clinical and laboratory features of DG and erythroleukemia (FAB M6) among 37 cases treated at a single institution over a 7-year period. DG was defined as >30% proerythroblasts and the absence of a myeloblastic component. Clinical and laboratory features were similar in both subtypes. High proportions of secondary leukemias and prior myelodysplastic syndromes (MDS) were noted (M6, 13 of 26 cases; DG, five of 11 cases; p = 0.85). Pancytopenia was common at presentation in both groups [median white blood cells (WBC), 2,600/mm3; HgB, 8.65 gm/dl; platelets, 38,000/microl]. Two-thirds of studied cases had chromosomal abnormalities typified by major karyotypic abnormalities (MAKA) involving three or more chromosomes. Abnormalities involving chromosome 5 and/or 7 occurred in 47% (48% M6 and 45% DG). Both erythroid malignancies carried a poor prognosis (M6, 6.0-month median survival; DG, 4-month survival; p = 0.74). Among those patients choosing aggressive rather than palliative therapy, higher remission rate (80 versus 25%) and survival advantage (11.5 versus 2.5 months) were seen in M6 compared to DG. However, only two long-term survivors exist. The similar clinical and laboratory features, cytogenetic patterns, and poor survival data suggest that the FAB classification schema should be modified to include DG.

Erythroleukemic infiltration of a lymph node: use of hemoglobin immunohistochemical techniques in diagnosis

Isolated submandibular adenopathy developed in a patient who had subacute erythroleukemia. Lymph node biopsy revealed a proliferation of immature cells and scattered foci of dyserythropoietic normoblasts. Since a review of the literature revealed no detailed description of an erythroleukemic lymph node infiltrate, a histopathologic study of this node was undertaken. The immature cells were identified as erythroblasts and pronormoblasts by histochemical staining (periodic acid-Schiff reagent and chloroacetate esterase), immunohistochemical reaction (directed against hemoglobin), and electron microscopy. The diagnosis of erythroleukemic lymph node infiltrate may be missed in the absence of a high index of suspicion. It is concluded that the detection of hemoglobin within malignant cells is most helpful in establishing the diagnosis.

Familial DiGuglielmo syndrome

DiGuglielmo syndrome is usually considered an idiopathic disorder occurring sporadically. A family in which DiGuglielmo syndrome occurred in 4 of 11 siblings is reported. A fifth sibling has developed unexplained marrow hypoplasia. Serial morphologic and cytochemical studies, supplemented by cytogenetic studies, documented the evolution of disease. Cytogenetic and environmental investigations did not explain this clustering of blood dyscrasias although a genetic predisposition to marrow damage by environmental factors cannot be excluded. The natural history of the disease in this sibship may consist of initial reactive changes in the marrow with subsequent progression to myelodysplasia with sideroblastosis and, finally, to DiGuglielmo syndrome.

Treatment of erythroleukemia with anthracycline antibiotics and cytosine arabinoside

The introduction of the anthracycline antibiotics and cytosine arabinoside have significantly improved the remission induction rate for patients with acute nonlymphocytic leukemia. Erythroleukemia (M6 by French-American-British classification) has long been considered to be resistant to chemotherapy. Since 1973 we have treated 14 patients with erythroleukemia with daunorubicin 45 mg/m2 or doxorubicin 30 mg/m2 for three days and cytosine arabinoside 100 mg/m2 by continuous infusion for 7 to 10 days. Six complete remissions (43%) were obtained with remission durations of 3+, 4+, 9, 13, 29+, and 35 months. While this remission rate is somewhat lower than that obtained with other types of acute nonlymphocytic leukemia, the combination of anthracycline antibiotics and cytosine arabinoside is clearly effective against erythroleukemia. Five patients treated before mid 1976 died soon after remission induction therapy was started. Four of these five patients were treated for 6 to 9 months with prednisone, halotestin, and/or splenectomy before remission induction chemotherapy was started and three of these patients died of systemic fungal infection, suggesting that these modalities of treatment may interfere with patient tolerance to remission induction therapy. It is suggested that erythroleukemia should be treated with intensive chemotherapy soon after the diagnosis is made.

Erythroleukemia: a study of 15 cases and literature review

Out of a total of 185 cases of acute leukemia at our institution from 1967 to 1978, fifteen cases (8.1%) were identified as erythroleukemia or erythremic myelosis. The symptoms at presentation were often related to anemia (10/15 cases); the presenting hemoglobin value was lower than 10.0 gm/100 ml. Nucleated red cells were present in the peripheral blood and reticulocyte response was inappropriate to the degree of anemia. Marrow biopsy showed erythroid hyperplasia with megaloblastic and dyserythropoietic features, increase in myeloblasts greater than 5% (10/15 cases), positive PAS staining of erythroid precursors (12/12 cases), and erythrophagocytosis by abnormal erythroid precursors (6/15 cases). Abnormalities were noted in monocytic and megakaryocytic cell lines, and it was concluded that erythroleukemia is probably a stem cell disorder. Response to chemotherapy was poor with median survival of four months from initial diagnosis. Intracranial hemorrhage and bacterial or fungal infection were the most frequent cause of death.

Prognostic factors and treatment effects on survival in erythroleukemia: a retrospective study of 134 cases

A total of 134 cases of erythroleukemia (119 from the literature and 15 of the authors' patients) were reviewed in an attempt to correlate survival with age, sex, hepatomegaly, splenomegaly, lymphadenopathy, infection, or hemorrhagic complications at initial presentation; hemoglobin (Hgb), white blood cell (WBC) count, and platelet count; percent myeloblasts in the marrow at diagnosis; and treatment regimens employed. Statistical methods included single classification analysis of variance, nonparametric analysis of variance (Kruskal-Wallis method), contingency table analysis, and correlation coefficient determination for numerical data. No significant correlation between survival and age, sex, hepatomegaly, lymphadenopathy, infection, or hemorrhagic phenomena was found. Improved survival was noted in patients without splenomegaly, and in daunorubicin-treated cases in contrast to those treated with other chemotherapeutic agents. A positive correlation between survival and initial Hgb and WBC was also noted. Erythroleukemia complicating a chronic myeloproliferative disorder had a worse prognosis than de novo erythroleukemia.

New aspects of preleukemic disorders

Preleukemic disorders are a controversial group of panmyelopathic disturbances that often precede the emergence of acute myeloblastic or myelomonocytic leukemia. In most instances, these preleukemic disorders are characterized by slowly developing myeloblastosis of the bone marrow. They include preleukemia, primary acquired panmyelopathy with myeloblastosis or smouldering acute leukemia, erythroleukemia, and subacute myelomonocytic leukemia. Sometimes, transitions between these various preleukemic disorders may be observed in a single individual. Abnormalities in cellular differentiation are expressed in cytochemical aberrations and in elaboration of colony forming units by marrow cells of patients with preleukemic disorders. Cytogenic and cellular kinetic abnormalities link preleukemic disorders closely to acute myeloblastic or myelomonocytic leukemia, although in many patients with preleukemic disorders, conversion to acute leukemia is not observed or perhaps not recognized. Understanding pathogenetic and pathophysiological aspects of preleukemic disorders may shed light on aspects of cellular proliferation and cellular differentiation in the acute leukemias.

Familial erythroleukaemia: a cytogenetic and haematological study

Clinical and haematological details of 2 siblings with a familial myeloproliferative disorder (erythroleukaemia) are presented. Their father is presumed to have died from a similar disease. The 2 siblings showed similar but not identical chromosomal abnormalities detected initially in marrow and later in peripheral blood. Serial studies revealed the emergence of an increasingly diverse pattern of chromosomal changes coincident with the haematological and clinical progression of the disease. Other members of the family were screened for cytogenetic and haematological changes. The paternal sibship displayed an increased incidence of cancer.

Preleukemia: does it exist?

In acute myeloid leukemia (AML), many of the remaining normal-appearing cells exhibit various abnormalities. An interpretation is that these cells are descendants of leukemic cells which have succeeded in overcoming the major final differentiation block that exists in AML. Direct evidence is quoted that red cell precursors in AML are of leukemic descent and it is claimed that the target cell of AML is the pluripotent stem cell. Next, evidence has been compiled that all three cell lines (red cell, n. granulocytes, platelets) exhibit qualitative defects in "prelukemia." Hence it is postulated that preleukemia per se doses not exist but that preleukemic states which with a rather high frequency sooner or later end in overt AML are actually true leukemias that, however, differentiate reasonably well. Another way of phrasing it is that preleukemic states are AMLs that present in partial and sometimes long-lasting remission, which only after months to years lose their differentiation ability and then are classified as AML.

The morphology of dyserythropoiesis in a patient with acute erythroleukaemia associated with multiple myeloma

A patient with multiple myeloma in whom acute erythroleukaemia developed 5 years following treatment with irradiation and melphalan is reported. Immunoglobulin synthesis and immunofluorescence investigations provided evidence that the blast cells in the peripheral blood did not belong to the plasma cell series; ultrastructure examination demonstrated their myeloid origin. Chromosomally abnormal cells were observed in both the bone marrow and peripheral blood. Light-and electron microscopy of erythropoiesis in this case showed distinct features of dyserythropoiesis, similar to those described in other entities. The erythroid cell abnormalities are discussed in the light of their being either indications of malignancy or of a reactive process.