Diagnostic criteria for hypocellular acute leukemia: a clinical entity distinct from overt acute leukemia and myelodysplastic syndrome

Clinical features and outcomes of hypocellular acute myeloid leukemia in adults: A Korean AML registry data

The hypocellular variant of acute myeloid leukemia (AML) is defined as bone marrow cellularity of <20% in a biopsy specimen at presentation. We performed a retrospective analysis of the clinical features and survival outcomes of hypocellular AML in a Korean population. We reviewed the medical records of all patients diagnosed with AML at nine hospitals participating in the Korean AML registry from 2006 to 2012. Overall survival (OS) and event-free survival (EFS) rates were calculated from the time of diagnosis until death or an event, respectively. In total, 2110 patients were enrolled and 102 (4.8%) were identified as having hypocellular AML. Patients with hypocellular AML were older than those with non-hypocellular AML (median age: 59 vs 49 years; P < .001) and presented with leukopenia more frequently (mean white blood cell count: 5810/μL vs 40549/μL; P < .001). There was no difference between patients with and without hypocellular AML in terms of the presence of antecedent hematologic disorders (5.9% vs 5.3%; P  = .809). FLT3-ITD and NPM1 mutations were less common in hypocellular than non-hypocellular AML (FLT3-ITD mutations: 1.2% vs 14.3%, P < .001; NPM1 mutations: 0% vs 9.5%, P = .019). No differences were seen between the hypocellular and non-hypocellular AML groups in the complete remission rate (53.9% vs 61.3%, P = .139) or early death rate (defined as any death before 8 weeks; 14.7% vs 13.0%, P = .629). The OS and EFS did not differ between the hypocellular and non-hypocellular AML groups (median OS: 16 vs 23 months, P = .169; median EFS: 6 vs 9 months, P = .215). Hypocellular AML is more frequently observed in older-aged patients and have fewer FLT3-ITD and NPM1 mutation, but the clinical outcomes of hypocellular AML do not differ from those of non-hypocellular AML.

Hypocellular acute myeloid leukemia treated with bone marrow transplantation

Hypocellular acute myeloid leukemia (AML) mainly occurs in elderly patients, and is extremely rare in childhood. There is still no established treatment for hypocellular AML. We report the case of an 11-year-old boy with hypocellular AML who was treated successfully with allogenic bone marrow transplantation (allo-BMT). He presented with fever, pallor and pancytopenia. Bone marrow aspiration and biopsy confirmed a diagnosis of hypocellular AML. Although low-dose cytarabine induced reduction of blasts, it did not lead to complete remission. He subsequently received myeloablative conditioning and allo-BMT. Graft-versus-host disease (GVHD) prophylaxis included short-course methotrexate and cyclosporine. Neutrophil engraftment (>5 × 10⁸ /L) and platelet recovery (>10 × 10¹⁰ /L) were achieved on days 13 and 27, respectively. He developed acute GVHD of the skin (grade 2), which responded well to treatment with prednisolone. He has remained in complete remission for 5 years since allo-BMT. We consider allo-BMT to be feasible for children with hypocellular AML.

HAG regimen improves survival in adult patients with hypocellular acute myeloid leukemia

Background

Hypocellular acute myeloid leukemia (Hypo-AML) is a rare disease entity. Studies investigating the biological characteristics of hypo-AML have been largely lacking. We examined the clinical and biological characteristics, as well as treatment outcomes of hypo-AML in our institutes over a seven years period.

Design and Methods

We retrospectively analyzed data on 631 adult AML patients diagnosed according to the French-American-British (FAB) classification and WHO classification of tumors of haematopoietic and lymphoid tissue, including 43 patients with hypo-AML. Biological variables, treatment outcomes and follow-up data on hypo-AML patients were analyzed.

Results

Out of 631 AML patients, 47 (7.4%) were diagnosed as hypo-AML, out of which 43 patients were evaluable. Compared with non-hypocellular AML, hypo-AML patients tended to be older (P = 0.05), more likely to present with leukocytopenia (P < 0.01) and anterior hematological diseases (P = 0.02). The overall complete remission (CR) rate, disease free survival (DFS), and overall survival (OS) in hypo-AML patients were comparable to those in non-hypo AML patients. Twenty-seven (62.8%) patients with hypocellular AML were treated with the standard regimen of anthracyclines and cytarabine (XA) (associated CR rate: 51.9%; median OS: 7 months; median DFS: 6.5 months). Sixteen (37.2%) patients were treated with a priming regimen containing homoharringtonine, cytarabine and G-CSF (HAG) (associated CR rate: 81.25%; median OS: 16 months; median DFS: 16 months).

Conclusions

The overall prognosis of hypo-AML was not inferior to that of non-hypo AML. HAG regimen might increase response rates and improve survival in hypo-AML patients.

Novel dynamin 2 mutations in adult T-cell acute lymphoblastic leukemia

Genetic mutations on signaling pathways are found in patients with T-cell acute lymphoblastic leukemia (T-ALL) and act as markers of high-risk leukemia. Mutations in dynamin 2 (DNM2) have been reported in T-ALL, particularly in early T-cell precursor-ALL. In the present study, DNM2 mutations were screened by sequencing DNM2 exons obtained by polymerase chain reaction amplification and gel purification in adult T-ALL patients. A total of 4 novel DNM2 mutations were identified in adult T-ALL patients, with a mutation rate of 9.5%, and the DNM2 mutations were found to co-exist with NOTCH1 and PHD finger protein 6, and were also associated with high-risk leukemia. A high rate of silent mutation was also found in the patients, but no significant association was found between the silent mutations and patients' clinical features. The present findings suggested the DNM2 mutations may be involved in the oncogenesis of T-ALL.

Successful treatment of childhood hypocellular acute myeloid leukemia

Hypocellular acute myeloid leukemia (AML) is extremely rare in childhood. We report on a 7-year-old girl with hypocellular AML who was treated successfully with granulocyte-colony stimulating factor (G-CSF) and combined chemotherapy. High-dose G-CSF induced complete remission and she subsequently received reduced intensity conditioning and unrelated cord blood transplantation; however, this resulted in early rejection. After a complete hematological recovery, she received 3 courses of combination chemotherapy oriented toward AML. She has remained in complete remission for over 1 year after the completion of the therapy. G-CSF effectively induced remission, and combination chemotherapy has been proven to be feasible for patients with childhood hypocellular AML.

Hypocellular acute myeloid leukemia in adults: analysis of the clinical outcome of 123 patients

BACKGROUND

The hypocellular variant of acute myeloid leukemia accounts for less than 10% of all cases of adult acute myeloid leukemia. It is defined by having less than 20 percent of cellular bone marrow in a biopsy at presentation. It is unclear in the literature whether the outcome of hypocellular acute myeloid leukemia differs from that of non-hypocellular acute myeloid leukemia.

DESIGN AND METHODS

We retrospectively analyzed all the cases reported to be hypocellular acute myeloid leukemia between 2000 and 2009. A second pathology review was conducted and the diagnosis was confirmed in all cases.

RESULTS

One hundred twenty-three (9%) patients were identified: patients with hypocellular acute myeloid leukemia were older than those with non-hypocellular acute myeloid leukemia (P=0.009) and more frequently presented with cytopenias (P<0.001). Forty-one patients with hypocellular acute myeloid leukemia had an antecedent hematologic disorder and 11 patients had received prior chemo-radiotherapy for non-hematopoietic neoplasms. On multivariate analysis, overall survival, remission duration and event-free survival were comparable to those of other patients with acute myeloid leukemia.

CONCLUSIONS

The outcome of hypocellular acute myeloid leukemia does not differ from that of non-hypocellular acute myeloid leukemia.

Hypocellular acute myeloid leukemia with bone marrow necrosis in young patients: two case reports

INTRODUCTION

Hypocellular variants of acute myeloid leukemia are very rare and almost always occur in old aged patients. In contrast, hypocellular acute lymphoblastic leukemia usually occurs in children.

CASE PRESENTATION

We report two Indian patients with hypocellular acute myeloid leukemia, a 32-year-old woman and a 13-year-old boy. Interestingly, one of the patients also showed bone marrow necrosis.

CONCLUSION

Hypocellular acute myeloid leukemia is a rare entity and can affect young individuals. It can be considered as a rare cause of bone marrow necrosis.

The hematopathological basis for studying effects of the demethylating agent 5-aza-2'-deoxycytidine (decitabine) in myelodysplasia

The myelodysplastic syndromes have, since their first recognition decades ago, been considered notoriously difficult with regard to their proper classification, determination of prognosis, and optimal treatment. With the advent of the French-American-British (FAB) classification, now aided but not superseded by the World Health Organization classification, distinct biological entities have been delineated, which in turn are very useful for stratification to different, established and experimental treatment modalities. However, precise subclassification of different types of myelodysplastic syndrome (MDS) is only possible with hematopathological studies based on the analysis of peripheral blood, bone marrow smear, and bone marrow biopsy, backed by appropriate clinical information. Bone marrow cytogenetics are also essential for any risk stratification since they still provide the second most powerful prognostic parameter after bone marrow blast enumeration. This paper will review the most important aspects of hematopathological diagnostics in MDS, risk scoring, and their application to the inclusion and stratification of patients into the European Organization for Research and Treatment of Cancer (EORTC)/German MDS Study Group Phase III multicenter trial of low-dose decitabine in patients more than 60 years old with high-risk MDS. Emphasis is placed on itemizing the broad spectrum of cytologic and histologic stigmata defining the myelodysplastic categories that are to be considered in this study.

Increased blasts mimicking acute leukemia in a patient with polysubstance abuse

Toxic insult to the bone marrow may result in partial or complete suppression, with or without reactive changes, and probable eventual regeneration of hematopoietic elements. During the regenerative process, increased blasts may be observed. Distinguishing these changes from an acute leukemic process can be difficult. In particular, the diagnosis of hypocellular bone marrow with increased blasts, also known as hypocellular or hypoplastic acute leukemia, presents a diagnostic dilemma for pathologists. We report a case of hypocellular marrow with increased blasts in a 50-year-old man with an extensive history of alcohol and drug abuse in whom chemotherapy was deferred. Recovery of peripheral blood cell counts and reticulocytosis occurred with withdrawal of the offending agents, and he remains alive and well 1 year later.

Clinical, haematological and histomorphological profile of adult myelodysplastic syndrome. Study of 96 cases in a single institute

Myelodysplastic syndromes (MDS) are clonal haematopoietic stem cell disorders characterised by ineffective and dyspoietic haematopoiesis. The natural history of these disorders is variable and ranges from a chronic to a rapid course towards leukaemic progression. Certain shortcomings have been encountered in the French-American-British (FAB) classification over the years, and therefore there is a need for an alternative method of classification. In 1999, the WHO published a revised classification of MDS. In the present study, we have analysed the clinical, haematological and histomorphological features in 96 cases of primary MDS seen in the department of haematology at the All India Institute of Medical Sciences (AIIMS) over a 6-yr period (1996-2001). Both FAB and WHO classifications have been incorporated and the Bournemouth scoring system applied in each case at presentation. The Bournemouth scoring system, in the absence of a cytogenetic study, offers a good prognostication and long-term survival estimate.

Acute myelogenous leukemia with splenic infarcts presenting as fulminant multi-organ failure

A 60-year-old male was admitted with leukopenia, thrombocytopenia, splenic infarcts and a normal peripheral smear. Within few hours he rapidly deteriorated with fatal multi-organ failure. Autopsy revealed massive infiltration of leukemic cells in several organs. Acute myelogenous leukemia should be considered in a patient presenting with unexplained multiorgan failure.

Adult hypocellular acute leukaemia with lymphoid differentiation

The rare hypocellular variants of acute leukemia (AL) previously also termed smouldering leukemia, almost always exhibit myeloid differentiation. Very rare cases of hypocellular AL with lymphoid differentiation have been reported, usually in children. This paper describes two cases (an 87-year-old woman and a 79-year-old man) in whom the blood findings were suggestive of AL. Paraffin-embedded bone marrow biopsy specimens revealed similar findings in both patients: there was severe hypocellularity, the cells of normal hemopoiesis were greatly reduced in number, and there was a diffuse increase in blast cells, which represented more than 50% of nucleated marrow cells. The blasts coexpressed TdT and CD34 and were negative for myeloperoxidase, CD117, CD68 and naphthol AS-D chloroacetate esterase. For the first time immunohistochemical Pax-5/CD34 doublestainings are provided, which revealed the blasts in one case to coexpress Pax-5 and CD34. All the blasts were CD79a-positive and 20% were also CD10-positive. In the other case, 20% of the blasts were CD79a-positive, 30% coexpressed Pax-5 and CD34 by doublestaining, and showed a clonal rearrangement of the immunoglobulin heavy chain gene. Thus a diagnosis of AL of lymphoid lineage, hypocellular variant, was made on the basis of immunohistochemical findings. The clinical course appears to be similar to that of hypocellular AML, as neither patient has developed overt leukemia during the one-year follow-up period.

Hypocellular acute promyelocytic leukemia with a tetraploid clone characterized by two t(15;17)

We describe a case of hypocellular acute promyelocytic leukemia with a tetraploid clone characterized by two t(15;17). The large leukemia cells had a bizarre nuclear configuration and multiple Auer rods. A bone marrow biopsy specimen revealed a markedly hypocellular marrow (<10% cellularity) in the absence of myelofibrosis. Myelodysplastic features were not detected. Chromosome analysis of marrow cells revealed a karyotype of 92,XXYY,del(2)(q?),t(15;17)(q22;q21)x2. Interphase fluorescence in situ hybridization revealed that the marrow cells were composed of a tetraploid clone carrying double t(15;17) and normal diploid cells. The leukemia responded well to all-trans retinoic acid. We think that the tetraploidy could be caused by endoreduplication or endomitosis of the diploid clone with single t(15;17). The unique karyotype largely contributed to the cell morphology and marrow hypoplasia, while it may not have affected on the prognosis of the acute promyelocytic leukemia.

De novo acute myeloid leukemia in the elderly; a consistent fraction of long-term survivors by standard-dose chemotherapy

To clarify the characteristics of de novo acute myeloid leukemia (AML) among the elderly, we reviewed 112 patients over 60 years old (median age 72 years) who were treated at hospitals in Nagasaki Prefecture with a population of 1.5 million between 1987 and 1994. Reclassification of morphological diagnosis revealed that the proportion of M3 was lower but that of M6 and the incidence of cases with trilineage dysplasia (TLD), known as poor prognostic features, were higher in the elderly than in patients less than 60 years old. Similarly, chromosomal data showed a lower frequency of favorable karyotypes such as t(8;21) and t(15;17) in the elderly. The overall survival of all 112 patients was 10.3% at 5 years. Multivariate analysis indicated that good performance status (PS), low WBC at diagnosis, standard dose multi-drug chemotherapy and all-trans retinoic acid (ATRA) treatment for M3 patients, and morphological findings without TLD were significantly correlated with longer survival. Most of the long-term survivors were found among those who received standard dose therapy in this series, although no consensus has been established how to treat elderly AML patients. We propose that a prospective controlled trial is necessary to confirm the role of standard dose chemotherapy for elderly patients with de novo AML.

Non-caseating granulomata associated with hypocellular myelodysplastic syndrome

Non-caseating granuloma (NCG) remains a histopathological hallmark for sarcoidosis. Although the exact mechanism for NCG formation is unknown, the pathogenesis may involve a disordered antigen presentation in the monocyte/macrophage system, functional abnormalities in activated T-lymphocytes and uncontrolled cytokine production. Similar immunological dysfunction has been described in myelodysplastic syndrome (MDS). However, the association of NCG and MDS is rarely documented. We report a case of hypocellular MDS associated with generalized NCG. Despite treatment for both sarcoidosis and tuberculosis, the patient failed to respond. A clonal myeloid disorder which was initially suppressed by T-cell immunosurveillance evolved after treatment with anti-thymocyte globulin. Although the coexistence of sarcoidosis remains a possibility, the lack of supportive clinical evidence of sarcoidosis, the abnormal appearances of the bone marrow, together with the failure to improve on high-dose steroid favour the clonal myeloid disorder as the sole pathology.

Biologic characteristics of patients with hypocellular myelodysplastic syndromes

Rates of proliferation and apoptosis as well as expression of tumor necrosis factor alpha (TNF-alpha), transforming growth factor beta (TGF-beta) and the number of macrophages were measured in bone marrow (BM) biopsies of 33 patients who presented with hypocellular (cellularity < 30%) myelodysplastic syndromes (MDS). Results showed that 2/3 of the patients had high apoptosis, high cytokine levels and large number of macrophages in their biopsies while 1/3 did not. Apoptosis and TNF-alpha levels were directly related (r = 0.583, P = 0.003, n = 24) as was apoptosis and the degree of anemia (P = 0.033, n = 18). A subgroup of patients with abnormalities of chromosomes 5 or 7 had higher platelets (P = 0.026) and higher apoptosis (P = 0.038) when compared with the rest of the group. Eight patients had no evidence of apoptosis and almost no detectable TNF-alpha in their biopsies. We conclude that within the hypocellular variant of MDS, there may be two distinct sub-groups of patients, one who present with high cytokine-mediated intramedullary apoptosis and the other who may be better characterized as having a stem-cell failure defect since they showed no evidence of apoptosis.

Myelodysplasia and the leukemias

The armistice after World War II marked the beginning of an era that was to last to the end of the present century. It was an era in which many changes in medicine and nursing combined to alter the entire philosophy of managing malignant disease. More specifically, the fluid-phase tumors, which comprise myelodysplasia and the leukemias, were singled out for special attention. First there was the ease with which blood and bone marrow could be sampled, making serial investigations simple and practical. Second, cytotoxic drugs became available ranging from nitrogen mustard through cytosine arabinoside, the anthracycline antibiotics, and the epi-podophyllotoxins. Although cytomorphology of the hematopoietic tissue had been exquisitely defined with the use of Romanowsky stains coupled with electron microscopy, the diagnosis of leukemia was, before 1945, a death sentence for want of effective therapy. This changed dramatically with the introduction of the folate antagonists, and progress was unremitting as the range of new products expanded. Suddenly responses could be obtained with single agents, and fairly rapidly combinations were developed for cumulative antitumor effect. Many agents had undesirable toxicity among different organs. Although slightly different for myeloblastic or lymphoblastic variants, this approach produced apparent disease eradication. The concept of complete remission, both clinical and hematologic, was born. Some of our early enthusiasm has had to be tempered with the somber appreciation that not all patients can improve and many others experience relapses. Where then do we stand? Leukemic cells themselves seldom kill. It is the relentless and uncontrolled expansion of a neoplastic clone that leads to bone marrow failure, albeit at different rates in the various subtypes. In the acute forms, the common presentation remains symptomatic anemia, neutropenic sepsis, and thrombocytopenic bleeding. Differentiation from marrow aplasia may not be possible at first on clinical grounds, although bone tenderness, gingival hypertrophy, and skin infiltration are among the general useful differential signs. Findings in the circulation and the marrow are of cardinal importance in diagnosis; they provide the basis for classification. Improved accuracy has followed the introduction of cytochemical stains, and a widening range of monoclonal antibodies, and greater recourse to karyotyping, have enhanced diagnostic acumen. Treatment decisions rest on many variables or prognostic factors that include age, performance status, comorbidity, and disease category, with an ever increasing regard for the part played by cellular and molecular genetics. Despite skillful utilization of this wealth of information for optimal management, outcome often leaves much to be desired. Myelodysplasia encompasses a number of different syndromes in which the refractory anemias are indolent, whereas those with excess blasts progress toward overt leukemia. Considerable judgment is necessary in selecting patients for whom supportive therapy alone is appropriate and recognizing others, up to one third of patients for whom use growth factors that include erythropoietin, granulocyte or granulocyte monocyte-colony stimulating factors, and thrombopoietin can be justified. The often unfavorable result has been a stimulus to current investigations that examine the value of intensive chemotherapy or the more innovative bone marrow transplantation and its peripheral blood equivalent. Autografting is a newer alternative that does not have proved potential. Acute leukemia, whether myeloblastic or lymphoblastic, has been managed with mixed success. Remission rates have steadily increased and, notably among children, moved toward 100% in certain groupings. The downside of nonspecific drug regimens is that some patients simply may not respond, whereas others experience remissions and then relapses. (ABSTRACT TRUNCATED)