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Disease Overview: Ring sideroblasts (RS) are erythroid precursors with abnormal perinuclear mitochondrial iron accumulation. Two myeloid neoplasms defined by the presence of RS, include refractory anemia with ring sideroblasts (RARS), now classified under myelodysplastic syndromes with RS (MDS-RS) and RARS with thrombocytosis (RARS-T); now called myelodysplastic/myeloproliferative neoplasm with RS and thrombocytosis (MDS/MPN-RS-T)., Diagnosis: MDS-RS is a lower risk MDS, with single or multilineage dysplasia (SLD/MLD), <5% bone marrow (BM) blasts and ≥15% BM RS (≥5% in the presence of SF3B1 mutations). MDS/MPN-RS-T, now a formal entity in the MDS/MPN overlap syndromes, has diagnostic features of MDS-RS-SLD, along with a platelet count ≥ 450 × 10(9)/L and large atypical megakaryocytes (similar to BCR-ABL1 negative MPN)., Mutations and Karyotype: Mutations in SF3B1 are seen in ≥80% of patients with MDS-RS-SLD and MDS/MPN-RS-T, and strongly correlate with the presence of BM RS; MDS/MPN-RS-T patients also demonstrate JAK2V617F, ASXL1, DNMT3A, SETBP1, and TET2 mutations; with ASXL1/SETBP1 mutations adversely impacting survival. Cytogenetic abnormalities are uncommon in both diseases., Risk Stratification: Most patients with MDS-RS-SLD are stratified into lower risk groups by the revised-International Prognostic Scoring System (R-IPSS). Disease outcome in MDS/MPN-RS-T is better than that of MDS-RS-SLD, but worse than that of essential thrombocythemia. Both diseases have a low risk of leukemic TREATMENT: Anemia and iron overload are complications seen in both and are managed similar to lower risk MDS and MPN. Aspirin therapy is reasonable in MDS/MPN-RS-T, especially in the presence of JAK2V617F, but the value of platelet-lowering drugs is uncertain., (© 2017 Wiley Periodicals, Inc.)

The term "refractory anemia" was used in 1937 by Cornelius Parker Rhoads to describe patients whose anemia did not improve after treatment with liver extract or iron salts, and this term has been used to denote patients with certain subtypes of myelodysplastic syndromes (MDS) since the 1976 and 1982 French-American-British (FAB) classifications of acute leukemias and MDS. In 2016, the World Health Organization (WHO) proposed elimination of "refractory anemia" in a more general proposal for reclassification of myeloid neoplasia. A scandal relating to Dr. Rhoads' possibly unethical medical experiments on anemic patients in Puerto Rico in 1931 and a racially offensive letter he wrote during that period prompted an international incident and Congressional-level inquiry. This dark history, as well as continued terminological problems with refractory anemia, suggest that this hoary term has indeed worn out its usefulness. This article reviews the history of "refractory anemia" and evolution in its use over the past 80 years. Rhoads' personal history, the potentially confusing nature of "refractory anemia", and the fact that it is possible none of the 100 patients Rhoads described in 1937 actually had MDS all support the new WHO reclassification proposal to eliminate this term., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Myelodysplastic syndromes (MDS) are myeloid disorders with various clinical and biological presentations. The French-American-British (FAB-1982) classification included five categories basing on morphology and bone marrow blast count. Three criteria are taken into account: 1) the percentage of blasts in peripheral blood and bone marrow, 2) the percentage of ringed sideroblasts, and 3) the number of monocytes in peripheral blood. The World Health Organization classification (WHO 2001, 2008) modifies the FAB system by also taking cytogenetic characteristics and molecular biology into consideration. The last classification (WHO-2008) takes into account: 1) the number of peripheral cytopenia, 2) the percentage of blasts in peripheral blood and bone marrow, 3) the percentage of ringed sideroblasts, 4) the possible presence of Auer Rods, and 5) the detection of a cytogenetic abnormality (the isolated 5q deletion). The following subgroups are defined: refractory cytopenia with unilineage dysplasia, refractory anemia with ringed sideroblasts, refractory cytopenia with multilineage dysplasia, refractory anemia with excess blasts, myelodysplastic syndrome unclassifiable and myelodysplastic syndrome with isolated del(5q).

To characterize bone marrow failure with del(13q), we reviewed clinical records of 22 bone marrow failure patients possessing del(13q) alone or del(13q) plus other abnormalities. All del(13q) patients were diagnosed with myelodysplastic syndrome-unclassified due to the absence of apparent dysplasia. Elevated glycosylphosphatidylinositol-anchored protein-deficient blood cell percentages were detected in all 16 with del(13q) alone and 3 of 6 (50%) patients with del(13q) plus other abnormalities. All 14 patients with del(13q) alone and 2 of 5 (40%) patients with del(13q) plus other abnormalities responded to immunosuppressive therapy with 10-year overall survival rates of 83% and 67%, respectively. Only 2 patients who had abnormalities in addition to the del(13q) abnormality developed acute myeloid leukemia. Given that myelodysplastic syndrome-unclassified with del(13q) is a benign bone marrow failure subset characterized by good response to immunosuppressive therapy and a high prevalence of increased glycosylphosphatidylinositol-anchored protein-deficient cells, del(13q) should not be considered an intermediate-risk chromosomal abnormality.

Distinguishing hypoplastic myelodysplastic syndrome from aplastic anemia (AA) is challenging. In the present study, Japanese and Chinese pediatric hematologists and pathologists conducted a joint review of bone marrow (BM) smears and trephine biopsies in 100 children with acquired BM failure syndrome, using the criteria proposed in the 2008 edition of the World Health Organization classification of hematopoietic and lymphoid tissues. The final consensus for the diagnoses of 100 children was AA in 29 patients, refractory cytopenia of childhood (RCC) in 58 patients, and refractory cytopenia with multilineage dysplasia (RCMD) in 13 patients. No significant differences between Japanese and Chinese children were found with regards to clinical and laboratory findings, or the distribution of diagnoses. Patients with RCC/RCMD showed milder disease severity and BM hypocellularity than those with AA. To establish the provisional entities for RCC, it is essential to prospectively compare the clinical outcomes between AA and RCC groups in a large number of patients.

We reported the different clinical features between Japanese and German refractory anemia (RA) patients in FAB classification. We re-analyzed the clinical features by WHO classification revised in 2008. The frequencies of refractory cytopenia with unilineage dysplasia (RCUD) and myelodysplastic syndrome-unclassified (MDS-U) with pancytopenia in Japanese patients were higher than in German patients (p<0.001). Refractory cytopenia with multilineage dysplasia patients showed the most unfavorable prognosis in both countries. The higher frequencies of MDS-U with pancytopenia and RCUD in Japanese patients may influence the different clinical characteristics between Japanese and German FAB-RA patients., (Copyright (c) 2010 Elsevier Ltd. All rights reserved.)

According to the revised WHO classification of 2008, dysplasia in > or = 10% of one bone marrow lineage and one cytopenia constitutes the low-risk category of unilineage cytopenia and unilineage dysplasia (UCUD). We retrospectively reclassified, according to WHO, low-risk MDS from our database and found 126 subjects with these features at diagnosis: 79 patients were categorized as refractory anemia (RA), 23 patients as refractory neutropenia (RN), and 24 as refractory thrombocytopenia (RT). We did not find differences between the three subgroups as regards sex, median age, and cytogenetic aberrations. Lower PMN count (0.8 x 10(9)/L) was observed in the RN category, as well as lower platelet count in the RT category (51 x 10(9)/L). Moreover, we found a lower rate of patients requiring RBC transfusions, during the disease course, in the RT category (45.8%) as compared to RA (62%) and RN (69%) groups (p = 0.05); a lower incidence of infections at diagnosis in the RT category (20.8%) compared to RA (32%) and RN (43%) categories (p = 0.03); and a higher incidence of hemorrhagic symptoms at diagnosis in the RT category (41.6%) and RN category (26%) as compared to the RA group (5%) (p = 0.001). Application of different scoring systems (Bournemouth and Spanish scores, WPSS) revealed a low OS in high-risk patients within the RT category, compared to RA and RN categories, although unlikely to reflect the consequences of low OS found in the former category. Statistically significant differences were also evidenced in the incidence of acute myeloid leukemia (AML) evolution and overall survival: 7/79 (8%) patients with the RA category evolved to AML in a median time of 89 months, whereas 4/23 (17%) of the RN category and 1/24 (4%) of the RT category experienced disease progression, in a median time of 33.8 and 12.8 months, respectively (p = 0.03). The RT category had a lower overall survival (15.9 months) as compared to RA (48.2 months) and RN (35.9 months) categories (p < 0.001). In conclusion, in our study, application of the revised 2008 WHO classification confirmed the importance of separating patients with unilineage dysplasia for prognostic disease assessment; from our results it seems that the RT category has a worse outcome.

Both the 2001 World Health Organisation (WHO) classification of haematopoietic neoplasms and the 2008 WHO classification revision include a distinctive diagnostic category, refractory anaemia with ring sideroblasts and thrombocytosis (RARS-T), to describe those rare patients who have both >or=15% ring sideroblasts and a sustained elevated platelet count. Recently, it has become clear that patients meeting WHO criteria for RARS-T have clonal JAK2(V617F) and MPL(W515) mutations at a similar rate to essential thrombocythaemia (ET). Given that the provisional classification of RARS-T as a myelodysplastic syndrome/myeloproliferative neoplasm (MDS/MPN) overlap syndrome, rather than as a form of MPN (i.e., ET), rests principally upon the presence of ring sideroblasts, which are a non-specific morphological finding, these new molecular results prompt reconsideration of the necessity for a distinctive RARS-T category. Here we review the historical developments that led up the definition of RARS-T as a disease entity, and we discuss conceptual understanding of RARS-T and arguments against continued use of RARS-T as a separate diagnostic category.

The 2001 World Health Organization (WHO)-sponsored classification of hematopoietic tumors has, for the first time, clearly defined a group of rare myeloid neoplasms termed myelodysplastic/myeloproliferative diseases (MDS/MPDs). This group includes three main entities, chronic myelomonocytic leukemia, atypical chronic myeloid leukemia and juvenile myelomonocytic leukemia, and also several less well defined, 'unclassifiable' disorders with MDS/MPN-like features. In the upcoming fourth edition of the WHO fascicle, due out later this year, the term 'MPD' is replaced by 'myeloproliferative neoplasm (MPN)'. Accordingly, the term MDS/MPD is being replaced by 'MDS/MPN' that will be used in this review. Although much progress has been made in understanding the molecular pathogenesis of myeloid neoplasms, most of the diseases included in the group of MDS/MPN still remain 'clinicopathologically assigned'. In other words, they can only be accurately categorized by a careful multiparametric approach that is based on the integration of bone marrow and peripheral blood morphology with other laboratory and clinical findings. The current 'spotlight' review provides practical guidelines, which should allow for a reproducible classification of these uncommon neoplasms when encountered in clinical practice.

Discovery of a constitutively activating point mutation of the Janus kinase 2 (JAK2) receptor-associated tyrosine kinase in patients with polycythemia vera (PV) and other BCR/ABL-negative myeloproliferative disorders prompted many groups around the world to examine diverse subsets of patients with myeloid diseases for the prevalence of the JAK2 V617F mutation and its clinical and pathological associations.

The main objective of this study was to evaluate the role of the recent World Health Organization (WHO) classification for assessing prognosis in patients with myelodysplastic syndromes (MDS). To this effect, we analyzed the prognostic impact of the WHO and French-American-British (FAB) morphologic classifications and of four different scoring systems in a series of 311 patients with primary MDS diagnosed between October 1990 and June 2001. Both the FAB and WHO classifications identified groups with different prognoses (p<0.0001), those presenting refractory anemia (RA) and refractory anemia with ringed sideroblasts (RARS) showing the best prognosis. The WHO classification subdivided RA into RA with only red cell dysplasia, and refractory cytopenia with multilineage dysplasia (RCMD), and RARS into RARS plus refractory cytopenia with multilineage dysplasia and ringed sideroblast (RCMD-RS). In our population, we have shown that the two subtypes characterized by dysplasia affecting exclusively the erythroid population (RA and RARS) have a better prognosis, with a median survival of 122.2 and 81.9 months, respectively, than those with multilineage dysplasia (RCMD and RCMD-RS) with a median survival of 32.3 and 43.2 months, respectively. There were no significant differences in median survival comparing RA with RAS (p<0.95), or comparing RCMD with RSCMD (p<0.97). Besides, the four scoring systems discriminated our MDS patients in terms of survival, and an increase in prognostic capacity was achieved on adding the score to the morphological classifications. Risk scoring had a greater prognostic impact than the FAB and WHO classifications. Prognostic scoring systems may be an important tool for risk stratification in hematological practice, and add significance to morphological classification. Combined application of the WHO classification and score system is useful for improving the identification of patients with a poorer prognosis. The WHO classification establishes more homogeneous subcategories than the FAB classification and is also able to identify groups with different prognoses.

Several reports indicate that there might be differences in clinical features between Asian and Western myelodysplastic syndrome (MDS) cases. We analyzed refractory anemia (RA) in French-American-British (FAB) classification cases diagnosed in Japan and Germany to perform a more exact comparison between Asian and Western MDS types. In the first step, we analyzed agreement of morphologic diagnosis between Japanese and German hematologists. Blood and bone marrow slides of 129 patients diagnosed with FAB-RA, FAB-RA with ringed sideroblasts (RARS), or aplastic anemia were selected randomly and evaluated separately by each group. The agreements of diagnoses according to FAB and World Health Organization (WHO) classifications were 98.4% and 83.8%, respectively. Second, we compared clinical features between 131 Japanese and 597 German patients with FAB-RA. Japanese patients were significantly younger than German patients. Japanese patients had more severe cytopenias. However, prognosis of Japanese patients was significantly more favorable than that of German patients. Japanese patients had a significantly lower cumulative risk of acute leukemia evolution than did German patients. Frequency of WHO-RA in Japanese patients with FAB-RA was significantly higher than that in German patients. In conclusion, our results indicate that the clinical features of Japanese patients with FAB-RA differ from those of German patients.

A clonal origin of hematopoiesis was studied by investigation of X-chromosome inactivation patterns (XCIP) in isolated granulocyte, CD14(+) and CD3(+) subpopulations obtained from bone marrow and peripheral blood of 36 female patients with primary myelodysplastic syndrome (MDS). Clonality was assessed by PCR amplification of polymorphic short tandem repeats of the human androgen receptor (HUMARA) gene and by investigation of silent polymorphism of iduronate sulphatase (IDS) or p55 genes. On the basis of results in a control group of 20 healthy age related females, a ratio of at least 9:1 between the two alleles was considered a significant marker of monoclonal hematopoiesis. Ten of the 11 patients with advanced forms of MDS (RAEB, RAEB-T, CMML) had clonal granulocytes and CD14(+) cells in peripheral blood. In patients with early disease, only 2 out of 11 patients (18%) with RA or RARS, according to WHO classification, had clonal granulocytes and CD14(+) cells in peripheral blood and bone marrow and 2 other patients with 5q-syndrome exhibited extremely oligoclonal granulocyte subpopulation in bone marrow. In contrast, we found clonal granulocytes in 12 out of 14 patients (86%) with refractory cytopenia with multilineage dysplasia (RCMD) and 8 of them simultanously exhibited clonal CD14(+) cells. Estimated 3 years survival of patients with early disease and clonal cell subpopulations was 61% as compared with 88% in patients without clonal hematopoiesis. Karyotype abnormalities were detected in 11 of the 25 females with early disease. Clonal patterns were present in 7 out of 8 patients with abberations diagnosed by routine cytogenetics, nevertheless, FISH revealed 5q deletion in 3 patients without signs of clonality in XCIP assay. No correlation was found between the presence of clonal subpopulations and the degree of telomere shortening in early MDS. Despite some limitations, the measurement of XCIP remains a sensitive tool for diagnosis of the first transforming mutation in the clonal development of MDS especially when combined with FISH and when an age related group is used to establish an appropriate allele ratio to exclude constitutional or acquired skewing. The occurrence of clonal cell subpopulations in most of the RCMD patients in contrast to RA may reflect a proposed multistep pathogenesis of MDS with dysplastic changes limited to erythropoiesis in early step and with subsequent development of multilineage dysplasia. The results also support the usefulness of separation of RCMD from 'pure' RA; however, a more complex insight combining different molecular techniques performed in a large number of patients is needed for refined classification of MDS on the basis of new molecular prognostic factors and for indication of more effective targeted therapy.

A retrospective analysis of the relationship between the initial classification according to either FAB or WHO criteria, the presence of risk factors and the type of therapy including stem cell transplantation (SCT) on the survival was performed in a group of 106 patients with primary myelodysplastic syndrome (MDS) of FAB RA subtype. Allogeneic SCT early in the course of the disease did not significantly affect median survival in RA patients evaluated either according to FAB criteria (63.2 months in 17 SCT patients versus 64.4 months in 89 non-transplanted (non-SCT) patients) or in subgroups classified separately according to WHO (64.0 months in SCT versus 91.0 months in non-SCT RA patients and 66.2 months in SCT versus 43.0 months in non-SCT refractory cytopenia with multilineage dysplasia (RCMD) patients) or International Prognostic Scoring System (IPSS) criteria despite decreased incidence of leukemic transformation (5% in SCT versus 32% in non-SCT patients). Neither univariate or multivariate analysis of different clinical and laboratory parameters revealed a significant effect of SCT on 3 or 5 years survival in RA patients. The most probable explanation was a relatively high rate of transplantation related mortality (41%) on one hand together with a slow disease progression towards leukemia (24% at 5 years in non-SCT) on the other hand. A more refined stratification of patients based on the combined WHO morphology classification and IPSS cytogenetic criteria revealed subgroup of 11 non-SCT patients with RCMD and poor karyotype with median survival significantly different from that in five SCT patients (9.2 months in non-SCT versus 89.3 months in SCT, P=0.05). Thus, combined WHO morphology/IPSS cytogenetics criteria may be helpful for identification of the high risk patients with the RA group who may benefit from early SCT despite the relatively high incidence of SCT-related complications.

The WHO classification for myelodysplastic syndromes (MDS) has introduced new categories with prognostic relevance. Our aim was to examine the predictive value of the WHO and the FAB classification compared to parameters of peripheral blood, bone marrow and IPSS. Clinical data, peripheral blood counts, bone marrow (BM) cytology and histology and survival were analyzed in consecutive newly diagnosed adult patients with MDS. All cases were diagnosed according to FAB criteria and reclassified by the WHO proposal. Among 150 patients entering the study median age was 58 years (12-90). According to FAB, 90 patients had refractory anemia (RA), 18 sideroblastic anemia, 34 refractory anemia with excess of blasts (RAEB), three RAEB-t and five chronic myelomonocytic leukemia. Using the WHO proposal, one half of the patients with RA changed category. One patient had the 5q-syndrome. There were 25 cases with refractory cytopenias with multilineage dysplasia (RCMD) and 23 WHO "unclassified". These last patients presented few cell atypias, favorable IPSS and a good survival as has been described for refractory cytopenias in pediatric MDS. Hypocellular BM was found in 24% of the patients. Karyotype was available in only 85 cases. In the univariate analysis, both classifications, hemoglobin values, hypercellular bone marrow and IPSS had an influence on survival. Using the bootstrap resampling as stability test for the model created by the multivariate analysis, the WHO classification entered the model in 73%, FAB in 38% and IPSS in only 7%. Therefore, in a setting with a high number of low-risk MDS, the WHO classification is the best predictor of survival of the patients.

A prognostic impact of WHO classification of myelodysplastic syndrome (MDS) was studied in a group of 103 primary MDS patients with refractory anemia (RA) according to French-American-British (FAB) classification. Median survival of 37 patients with RA according to WHO criteria of 85.2 months was significantly different from that in both 37 patients with refractory cytopenia with multilineage dysplasia (RCMD) (47.0 months, P=0.002) and 29 patients with 5q- abnormality diagnosed by routine chromosome banding (36.2 months, P=0.0002). A more detailed karyotype analysis with fluorescent in situ hybridization (FISH) techniques confirmed 5q deletion as a sole cytogenetic abnormality in only 12 out of 29 patients, in 4 patients 5q- was associated with complex abnormalities involving 5q region, 13 patients had 5q deletion combined with further karyotype abberations outside 5q. No difference in median survival and estimated 3 years survival was observed between RA patients, patients with 5q- syndrome according to WHO morphology criteria and patients with 5q- as a single abnormality confirmed by FISH in contrast to patients with either additional 5q abberations or further karyotype changes not involving 5q. The same difference was also observed in time to 25% of patients evolving to acute myeloid leukemia (AML). Our study confirmed usefulness of separation of RCMD from RA. RCMD represents a poor prognostic subgroup of MDS clearly distinct from pure RA mainly due to short survival connected with progressive bone marrow failure and increased risk of leukemic transformation. We also suggest to define 5q- syndrome as primary MDS of FAB type RA with 5q deletion as a sole cytogenetic abnormality confirmed by FISH analysis. This definition enabled us to discriminate 5q- patients with favorable prognosis similar as in RA from those with poor outcome associated with 5q- combined with complex abnormalities involving either 5q or regions outside 5q.

The colony-forming capacity of the peripheral blood stem/progenitor cells (PBSC) in different forms of myelodysplastic syndrome (MDS) was investigated. In most cases of refractory anemia (RA) the colony growth of PBSC was definitely reduced as compared to the controls. However, in RA with unfavorable chromosomal aberrations, in refractory anemia with ringed sideroblasts (RARS) and in advanced stages of MDS such as refractory anemia with excess blasts (RAEB) and refractory anemia in transformation (RAEB-t), the number of myeloid progenitor cells increased up to 100-fold. In chronic myelomonocytic leukemia (CMML), the increase was even more marked, up to 350-fold. Although the number of PBSC was strongly elevated, these cells were not able to restore hematopoiesis in vivo. In conclusion, the increase of circulating colony-forming cells (CFC) seems to be associated with disease progression, and thus, the evaluation of PBSC could be an important parameter in the diagnosis of MDS.

The French-American-British classification of myelodysplastic syndromes (MDS) has contributed greatly to better communication and conduct of clinical trials. However, the advent of novel cytogenetic, immunological and molecular techniques in recent years warrant some alterations to this purely morphological classification. This review aims at highlighting the advances which reflect more closely the unique biological and clinical features of various subtypes of MDS. We propose a comprehensive classification of MDS, to include the newly defined categories, as well as those not included in previous classifications, such as the therapy-induced and hereditary MDS. We hope that this classification will help in focusing attention on the biological features of MDS, the understanding of which will be crucial to combat this disease.

Apoptosis of hematopoietic progenitor cells is increased in myelodysplastic syndromes (MDS). We have studied Fas (CD95/Apo-1) antigen expression in 27 MDS patients (RARS 4, RA 3, RAEB 13; RAEB-t 3, CMML 4) and three AML secondary to MDS. We found that the Fas antigen was not expressed on normal bone marrow (BM) CD34+, CD14+, or glycophorin+ cells, and only slightly on CD33+ cells. Patients with MDS had upregulation of Fas expression on total bone marrow nuclear cells (BMMC) (t-test, P = 0.04), CD34+ (P = 0.013), CD33+ (P = 0.04), and glycophorin+ (P = 0.032) BM cells compared to controls. Fas expression did not correlate to the FAB subtype, the Bournemouth score, or to peripheral cytopenias. However, Fas expression intensity on CD34+ cells negatively correlated to the BM blasts number (Spearman, P = 0.01) suggesting that leukemic blasts cells lose Fas antigen expression with progression of myelodysplasia. Using both proliferation assays in liquid cultures and clonogenic progenitor assays in the presence of an agonist anti-Fas MoAb (CH11), we showed that the Fas protein was functional in some patients. Dose-dependent inhibition of DNA synthesis was observed in three out of seven patients studied. CFU-GM and BFU-E colonies suppression in some patients suggested that Fas can induce apoptosis in myeloid and erythroid BM progenitors of MDS patients. The TUNEL technique on BM smears gave a mean of 12.6% +/- 2.5 of bone marrow apoptotic cells in five controls. Patients with MDS had increased bone marrow apoptosis (mean 39% +/- 5.7, t-test, P = 0.012). Four out of 15 (26%) patients studied with a sensitive radiolabeled DNA ladder technique had typical DNA ladders indicative of advanced stages of apoptosis. Massive BM suicide was observed in patients with RA (2/2) and RAEB (8/11), whereas apoptosis rates were normal or low in patients with RAEB-t (3/3) or secondary AMLs (3/3). Moreover, high rates of apoptosis correlated to low Bournemouth score (Spearman, P = 0.01). No statistical correlation could be found between Fas expression and apoptosis rates. Our results confirm the importance of programmed cell death in MDS. The Fas antigen is clearly upregulated on BM cells, but its role in the pathophysiology of apoptosis in myelodysplasia is still unclear, indicating that many factors positively or negatively interfere with the Fas-mediated pathway of apoptosis in vivo and in vitro.

The myelodysplastic syndromes (MDSs) are a group of haematological disorders found predominantly in the elderly, and are defined by morphological abnormalities of the three cell lines. None of the abnormalities is specific for MDS but, when combined with active or hyperactive haemopoiesis and refractory cytopenia in an elderly person, they suggest the diagnosis. The French-American-British co-operative group divided MDSs into five types: refractory anaemia; refractory anaemia with ring sideroblasts; refractory anaemia with excess of blasts; refractory anaemia with excess of blasts in transformation; and chronic myelomonocytic leukaemia. The classification was based on the number of blasts in the bone marrow, dysplastic features in one or more cell lines, ringed sideroblasts, blasts in the peripheral blood, Auer rods in the granulocyte precursors and absolute monocytosis. MDS can be a primary condition and of unknown aetiology or develop secondary to the action of a known agent such as an alkylating agent, chemical or recombinant human granulocyte colony-stimulating factor. The pathogenesis of MDS is thought to be a multi-step process which begins with a somatic mutation in the pluripotential stem cell, is irreversibly altered and acquires a survival advantage. The abnormal clone expands at the expense of normal haemopoiesis and undergoes further genetic change to give a progressively more malignant phenotype. Present theories of the development of MDS are speculative but further research could cast light on the development of other haematological disorders.

Aplastic anemia, myelodysplastic syndromes (MDS) and chronic myeloproliferative diseases (MPD) are stem cell disorders. There is no clear-cut demarcation of them. Hypoplastic MDS displays features of aplastic anemia and MDS, on the other side mixed myelodysplastic and myeloproliferative syndromes (MDS-MPS) develop. In our collection of 566 MDS patients, features of myelodysplasia as well as myeloproliferation, MDS-MPS, were present in 25 patients (4.4%). Twelve patients had at the time of diagnosis megakaryocytic proliferation and thrombocythemia beside signs of MDS, and seven had myelodysplasia with granulocytic proliferation and leukocytosis. In another six patients, MDS was the first diagnosis and the proliferative phase developed later during the course of the disease. These patients can be characterized as MDS-MPS in evolution. All subjects had a variable degree of anemia. While the level of thrombocythemia has been relatively stable, the number of leukocytes has been progressive, but rarely extended beyond 100 x 10(9)/l. Ring-sideroblasts and myelofibrosis were frequent findings. Two more homogeneous MDS-MPS groups emerged in our analysis: sideroblastic anemia with thrombocythemia and a group fulfilling the criteria of Philadelphia chromosome negative and bcr-abl negative "atypical chronic myeloid leukemia (aCML)'. One patient with thrombocythemia and three with leukocytosis (23%) transformed to acute myeloid leukemia (AML). Men prevailed (12/13) in patients with leukocytosis and MDS-MPS in evolution. Of the 46% MDS-MPS patients with chromosomal aberrations, del(20)(q) is of interest.

Clinical, haematological and outcome data were studied in 84 patients with acquired idiopathic sideroblastic anaemia (AISA) from a registry of 613 consecutive myelodysplastic syndromes (MDS) recorded by five institutions in western France. Two groups could be identified and compared: 'pure' erythroblastic AISA (AISA-E: 59 pts), and AISA with myelodysplastic features, i.e. dysgranulo and/or dysmegakaryopoiesis (AISA-M: 25 pts). Results were also compared to those of a series of 71 cases of refractory anaemia without sideroblastosis (RA) carried out from the same registry. Dyserythropoiesis was present in 90% of all AISA subtypes, dysgranulopoiesis in 88% of the AISA-M cases; dysmegakaryopoiesis was observed in 44% of AISA-M. Ten patients with both forms of AISA showed high platelet counts. These cases appeared particular in that four of them were associated with a splenomegaly and/or a hyperleucocytosis. They had to be distinguished from myeloproliferative syndromes. Outcome comparison of AISA-E with AISA-M showed a significant discrepancy of survival duration (60 vs 38 months respectively). Progression towards refractory anaemia with excess of blasts or acute leukaemia, was significantly higher for AISA-M than for AISA-E. The risk of transformation increased to 24% for the AISA-M group similarly to those of RA patients (17%). We conclude that AISA must be divided into two categories, 'pure' AISA and AISA-M, because survival duration and risk of transformation are different.

Twenty-three patients with bicytopenia or pancytopenia were retrospectively studied. The patients with underlying disorders, blast count of more than 5% on bone marrow (BM) aspirate, blast count of more than 1% on peripheral blood or ringed sideroblast count of more than 15% on BM aspirate were excluded. According to Yoshida's criteria, 23 patients were classified into 6 subtypes [AA (aplastic anemia)1: typical AA, AA2: atypical AA, MDS (myelodysplastic syndrome)3: typical RA (refractory anemia, MDS4-6: atypical RA], and AA1 7 cases; AA2 2 cases; MDS3 5 cases; MDS4 1 case; MDS5 2 cases; MDS6 6 cases. To clarify the clinical features of atypical RA group (MDS4-6), we investigated ferrokinetics, RBC life span, karyotype, serum Epo (erythropoietin) concentration, response to therapy and prognosis. Results were as follows: 1) all three RA patients who were younger than 30 years old were included in atypical RA group, 2) in ferrokinetics study PID (plasma iron disappearance time) values of MDS4 and MDS6 patients ranged between those of AA1 and those of MDS3 patients (5 of 7 patients), 3) two cases who developed leukemia belonged to typical RA group, 4) patients with atypical RA showed response to therapy and their prognosis were better than those with typical RA. These observations suggest that atypical RA have different clinical features from typical RA.

We analysed the course and clinical features of a series of refractory anaemias (RA, RAEB, RAEBt). We could not find evidence to support the hypothesis that these three MDS classes are inevitably subsequent events of a single disease. Therefore aggressive treatment of RA, aimed at avoiding its evolution to RAEB or RAEBt, does not seem justified.

The bone marrow smears and marrow biopsies of 30 unselected consecutive patients with a myelodysplastic syndrome have been classified retrospectively according to the proposals of the French-American-British cooperative group (FAB). The diagnoses according to the FAB classification were refractory anemia (RA) in 3, RA with ring sideroblasts (RAS) in 5, RA with excess of blasts (RAEB) in 14, REAB in transformation (RAEB-t) in 5, and chronic myelomonocytic leukemia (CMML) in 3. The group comprised 19 men and 11 women with a median age of 68 years. Of 22 patients, 9 died after progression to acute non lymphoblastic leukemia (ANLL), 7 from infections, 2 from bleeding and 4 from unrelated causes. Actuarial survival is 10.5 months, 8 patients being at risk at the time of evaluation. Although the small number of patients does not allow statistical evaluation, our results are similar to those in the literature: prognosis is less good with an increasing number of marrow blasts and degree of cytopenia, and the risk of progression to ANLL is higher for REAB-t and REAB patients. Of 4 patients treated with small doses of cytosine-arabinoside (Ara-C), one responded and remained stable without treatment for 7 months. 2 patients resistant to small-dose Ara-C showed complete response to subsequent high-dose Ara-C treatment.

Anatomical observations have indicated a decrease of marrow cellularity with age, but these changes are not associated with anemia in the healthy geriatric patient. Aged patients with refractory anemia should be studied by utilizing red cell volume (MCV) and red cell heterogeneity (RDW). A classification with these indices initially can separate the anemias for a more fruitful investigation. By old age the anemias of hereditary red cell membrane or hemoglobin disorders should be known to the patient. In the absence of tumor, elderly patients have an increasing frequency of refractory anemias that can be called preleukemia or myelodysplastic syndrome. Morphological observations have emphasized the importance of abnormal megakaryocytes and platelets in all phases of preleukemia, and these cytologic changes should be used to guide the physician in the early diagnosis of the syndrome complex. This group of refractory anemias have a limited survival, but nonspecific marrow stimulation can be effective and should be tried. With a more complete classification of the chromosomal abnormalities in the myelodysplastic syndrome, a more accurate prognosis can be anticipated. The anemias of marrow aplasia and ineffective iron utilization (anemia of chronic disease) are found frequently in the elderly, and the physician may offer more effective therapy by an early diagnosis.