The prognostic significance of auer rods in myelodysplasia

Revisiting Howell-Jolly Body-Like Cytoplasmic Inclusions in Neutrophils: A Report of Two Cases and Confirmation of Nuclear Origin

Howell-Jolly body-like inclusions in neutrophils have been reported in a handful of reports; however, their nuclear origin has never been confirmed to date. We report the presence of these cytoplasmic inclusions in two cases and confirm their DNA-based origin by fluorescent nuclear staining. Peripheral blood smears were manually reviewed by light microscopy and after 4',6-diamidino-2-phenylindole (DAPI) fluorescent staining via confocal microscopy. Methanol fixed peripheral blood smears were incubated with DAPI (Sigma Aldrich, St. Loius, MO, USA) and coverslipped with mounting media. DAPI-stained cells were imaged with a Leica SPE confocal microscope using a 405 nm excitation laser and a 63×/1.3 NA oil immersion objective. Optical sections spanning the entire cell thickness were acquired and maximum intensity projections were produced in ImageJ. Both cases described herein had Howell-Jolly body-like inclusions similar to those reported in the literature. Testing for relevant infectious etiologies was negative. Positive staining on fluorescence microscopy confirmed DNA-based origin of this cytoplasmic inclusion material. These DNA-based inclusions occur in the immunosuppressed patient and mimic infectious inclusions. While morphologically worrisome, recognition of these inclusions may prevent unnecessary treatment and testing in clinically appropriate patients.

Refractory anemia with excess of blasts in transformation: analysis of reclassification according to the WHO proposals

The category of "refractory anemia with excess blasts in transformation" (RAEB-T) has been abandoned in the new WHO-classification of myelodysplastic syndromes (MDS). The majority of patients previously belonging to this category are now classified as acute myeloid leukaemia (AML). In the FAB-classification, patients had been assigned to the RAEB-T category if they had either (1) a medullary blast count between 20 and 30% or (2) a peripheral blast count of at least 5%, or (3) Auer rods detectable, irrespective of the blast count. We analyzed these subtypes of RAEB-T in terms of hematological characteristics, karyotype anomalies, and prognosis. Patients with more than 20% medullary blasts and patients with at least 5% peripheral blasts as the sole defining parameter for RAEB-T had a median survival of 6 months, as compared to 11 months in patients with Auer rods as the sole defining parameter. The presence of Auer rods therefore does not convey a particularly bad prognosis and does not justify placing patients in a high-risk category of MDS or even classifying them as AML. This finding supports the elimination of Auer rods as a parameter for classification in the new WHO system. On the other hand, the reclassification into RAEB II (according to WHO proposals) of previous RAEB-T patients with a peripheral blast count of at least 5% is problematic, because this feature predicts a median survival not different from that of AML patients.

Dyshaemopoiesis in adults: a practical classification for diagnosis and management

Dyshaemopoiesis is a heterogeneous disease that may be classified into non-clonal and clonal dyshaemopoiesis. Non-clonal dyshaemopoiesis comprises reversible disorders with DNA synthesis impairment in dividing cells of the bone marrow by avitaminosis through various mechanisms or direct DNA damage from multiple causes. Complete haematologic recovery is obtained after vitamin supplementation or suppression of a myelotoxic agent. On the contrary, clonal dyshaemopoiesis is a group of chronic and usually irreversible diseases that may culminate in acute leukaemia (AL). These so called myelodysplastic syndromes (MDS) and their variants may be classified as primary, secondary and other diseases with doubtful clonality. A detailed classification of dyshaemopoiesis in adults may offer partial help in the diagnosis and management of dyshaemopoiesis. Pathobiological studies in progress allow better understanding of MDS and consequently the establishment of new modalities of treatment.

Myelodysplastic syndromes in childhood: is the FAB classification relevant? Report of 81 children from a French multicentre study. French Group of Cellular Hematology

We reviewed the peripheral blood and bone marrow smears of 81 children with myelodysplastic syndrome (MDS). The morphological FAB classification was applicable in 59 children (72.8%): RAEB and RAEBt were the most frequent, 32 cases (39.5%). CMML was observed in 15 cases (18.5%) and in 25% of them, serological evidence for a recent EBV infection was demonstrated. In 22 cases (27.2%), the FAB classification was not convenient. In some of these children, dysmyelopoiesis was associated with constitutional disorders. Among these various inherited conditions, Down syndrome in which myelodysplasia is the expression of an abnormal clonal hematopoiesis, and mitochondrial cytopathies in which MDS is the hematological expression of a polyclonal multi-organ disease. The FAB classification does not appear to be satisfactory for all the disorders included in the group of childhood MDS and should be modified for specific use in children.

Treatment and prognostic factors in myelodysplastic syndromes

While MDS remains an enigmatic disease, substantial progress has been made in the elucidation of its origin and the better understanding of its natural course. The advent of newer molecular and cytogenetic techniques has tremendously improved the 'older' morphological and histopathological prognostic criteria. More refined scoring systems may ultimately allow for individualized treatment programmes which will better preserve quality of life, while at the same time offer improved chances for survival and cure. Much can be expected from newer cytokines, such as thrombopoietin, stem cell factor, interleukin-11 or of the combination of different cytokines and growth factors, to alleviate MDS-symptoms and to possibly alter the course of the disease. After the initial disappointment with differentiation inducers, the availability of newer agents and/of combinations may offer better perspectives for the future. Much interest will also be generated on the use of mdr-reversal agents in the attempts to improve on chemotherapeutic efficacy. Finally, while allogeneic transplantation still remains the only option for definite cure of the disease, the spectacular advances made in the use and manipulation of autologous peripheral blood haemopoietic stem cells probably constitute the best hope for brightening the grim outlook most MDS patients still have.

FAB classification of myelodysplastic syndromes: merits and controversies

Guidelines for the definition and diagnosis of myelodysplasia were set out by the French-American-British Cooperative group (FAB), and the resulting framework has greatly helped the now very large number of workers in many scientific disciplines who are actively investigating the myelodysplastic syndromes (MDS). Most patients with MDS can be readily classified into clinically relevant subgroups by correlation of clinical findings with the findings from well-prepared peripheral blood and bone marrow specimens. However, there are several areas where the standard morphological features are insensitive, but integration of these parameters with histology and cytogenetic and molecular techniques may help us in understanding this fascinating disease.

Routine and specialised techniques in the diagnosis of haematological neoplasms

The relative importance of traditional techniques used in the diagnosis of haematological neoplasms has altered during the past decade. Cytology and histology retain their central role but the importance of cytochemistry has declined, except in the diagnosis of AML. Immunophenotyping is of major importance in the diagnosis of ALL, some categories of AML and the LPDs. Cytogenetic and molecular genetic analysis are important in the diagnosis of CML and are becoming increasingly important in the diagnosis of chronic LPDs and other haematological neoplasms. Diagnostic haematology laboratories which are not specialist leukaemia centres should have ready access to all of these techniques to ensure optimal patient management. However, not all techniques need to be performed in every laboratory.

The contribution of Auer rods to the classification and prognosis of myelodysplastic syndromes

Auer rods were first recognized at the beginning of this century. Their presence soon became considered to be an unequivocal manifestation of a leukemic process. Possibly influenced by this long-held assumption, in 1982 the French-American-British co-operative group (FAB) incorporated the presence of Auer rods into a classification system of the myelodysplastic syndromes that remains in widespread clinical usage today. Although unsubstantiated at the time, the presence of Auer rods was suggested to indicate a rapidly progressive disorder and a poor prognosis. In the absence of studies confirming the utility of Auer rods as a diagnostic criterion, the FAB classification system of myelodysplastic syndromes has been widely used to allocate therapy. In this review we examine the early descriptions of Auer rods and critically evaluate the studies examining the value their presence has in the classification and prognosis of patients with myelodysplastic syndromes.

Life expectancy in primary myelodysplastic syndromes: a prognostic score based upon histopathology from bone marrow biopsies of 569 patients

The retrospective evaluation of bone marrow biopsies of 569 patients with primary myelodysplastic syndrome--pMDS--revealed 256 refractory anemias--RA--, 52 refractory anemias with ringed sideroblasts--RARS--, 133 refractory anemias with excess of blasts--RAEB--, 52 refractory anemias with excess of blasts in transformation--RAEB-t--, and 53 chronic myelo-monocytic leukemias--CMMOL--according to FAB-criteria, 23 patients were not otherwise specified (myelodysplastic syndrome: not otherwise specified--MDS.NOS--). RARS-patients had the best prognosis (median survival 41.9 months, incidence of leukemia 3.8%), followed by RA-patients (26.5 months, 16.4%), MDS.NOS-patients (22.4 months, 21.7%), CMMOL-patients (12.5 months, 49.1%). RAEB- and RAEB-t-patients had the worst prognosis (median survival time 8.5 and 4.6 months, incidence of leukemia 42.1% and 57.7%, respectively). But the survival times showed a considerable range in each FAB-subgroup with 0-154 months in RA or 0-52 months in CMMOL. To forecast life expectancy more precisely, a scoring system was developed using nine histopathological parameters, among which the three most important ones were determined: quantity of myeloblasts, myelofibrosis and ALIP's. The scoring system allows a determination of three risk groups with significantly different survival times. It is valid also for patients without increase of myeloblasts (< 5% myeloblasts in the bone marrow) and identifies high-risk MDS patients in this group. By this proposed scoring system, a prognostic approval in primary MDS can be achieved applying histopathology without regarding further methods herewith presenting a system which could be considered independently from hematologic, cytological or laboratory data.

New treatment approaches for myelodysplastic syndrome and secondary leukaemias

Allogeneic BMT is the treatment of choice for patients with MDS or sAML, offering a good chance of long-term disease-free survival if the transplant is performed in an early stage of disease or if the patient receives the transplant in complete remission after polychemotherapy. The transplant is limited to a minority of relatively young patients (aged below 55 years) with an HLA-identical sibling. Allogeneic BMT may also be considered when a closely- or fully-matched unrelated donor has been identified for a young and fit patient. All patients, including those without an excess of blasts, should be conditioned with bone marrow ablative therapy rather than an immune suppressive regime, such as cyclophosphamide alone. For the majority of patients there is no standard therapy other than appropriate supportive care. Relatively young patients below the age of 60 years with poor risk features can be considered for treatment with combination chemotherapy. Maintaining remission after remission-induction chemotherapy is a difficult issue. Patients not eligible for allogeneic BMT could be treated with post-remission chemotherapy or autologous BMT in the framework of prospective studies. Older patients can be considered for treatment with haematopoietic growth factors alone or in combination with differentiating agents such as low-dose Ara-C. This treatment should be delivered within the context of carefully designed and conducted trials.