[Clinical course, morphology and prognosis of chronic myelomonocytic leukemia]. / Klinik, Morphologie und Prognose chronischer myelomonozytärer Leukämien.

BACKGROUND: The FAB group proposed to distinguish 2 subgroups of chronic myelomonocytic leukemia (CMML): Depending on the total leukocyte count a myelodysplastic type (< 13,000/microliter) was separated from a myeloproliferative type (> 13,000/microliter). Prognostic factors are not well-established until now. PATIENTS AND METHODS: Based on retrospective analyses of patients with CMML diagnosed at our institution, we compared the presenting clinical and hematological features of both disorders and examined the natural course of the disease and prognostic factors. RESULTS: Out of 225 patients with CMML there were 115 patients with myelodysplastic type (MDS-CMML) and 110 patients with myeloproliferative type (MPD-CMML). Median age of patients at diagnosis and sex ratio were not different. Splenomegaly and hepatomegaly were more common in MPD-CMML. With regard to laboratory findings, patients with MPD-CMML presented with significantly higher LDH values. Except for WBC, peripheral blood counts were not different. Median percentage of bone marrow blasts was 8% in both disorders. Signs of bone marrow dysplasia were comparable in both disorders. Cumulative survival rates were similar in both disorders. Five years after diagnosis, actuarial survival for patients with MPD-CMML was 24%, as compared to 15% for patients with MDS-CMML. The probability of transformation to AML was higher in MDS-CMML (29% vs 18% after 5 years). Elevated LDH values, low hemoglobin values and male sex were independent risk factors for the entire group and for the MDS-CMML group. Using the Düsseldorf score, we could define risk groups within MDS-CMML with a median survial of 12 vs 40 months (p = 0.00005). Prognostic factors could not define risk groups within the MPD-CMML group. CONCLUSIONS: In summary, these data suggest that MDS-CMML and MPD-CMML are clinically distinguishing conditions, but the separation provides little prognostic information. The Düsseldorf score can be used to provide risk stratification in CMML.

[Role of aggressive treatment strategies for myelodysplastic syndromes]. / Stellenwert aggressiver Behandlungsstrategien im Therapiekonzept myelodysplastischer Syndrome.

Myelodysplastic syndromes (MDS) constitute a heterogenous group of acquired bone marrow disorders characterized by ineffective hematopoiesis, cellular dysfunction and an increased risk of transformation into acute myeloid leukemia (AML). The percentage of medullary blast cells and the karyotype at diagnosis are the most important predictors of survival. Patients with more than 10% blast cells or an unfavourable karyotype (chromosome 7 abnormalities or complex aberrations) usually survive less than 12 months. This review article focuses on the roles of intensive AML-type chemotherapy, autologous stem cell transplantation and allogeneic bone marrow transplantation in the management of patients with advanced MDS. Recent studies suggest that, with appropriate selection of patients, intensive chemotherapy produces high rates of complete remission. Chances of entering remission are particularly high in patients with a good Karnofsky score, bone marrow blast count < 30% and normal karyotype. When compared with acute myeloid leukemia, results of autologous bone marrow transplantation in MDS are disappointing. A major disadvantage of this approach is the delayed recovery of hematopoiesis. Autologous peripheral blood progenitor cell transplantation overcomes this difficulty and is currently explored as consolidation therapy after successful remission induction with polychemotherapy in an intergroup study of the EORTC and EBMT. Allogeneic bone marrow transplantation remains the treatment of choice for younger MDS patients, offering a good chance of cure if the transplantation is performed at an early stage of disease or if the patient receives the transplant in complete remission after conventional chemotherapy.

Problems in the classification of CMML--dysplastic versus proliferative type.

The FAB group proposed to distinguish two subgroups of chronic myelomonocytic leukemia (CMML). Depending on the total leukocyte count, a myelodysplastic type (MDS-CMML) (< or = 13,000 microl(-1)) was separated from a myeloproliferative type (MPD-CMML) (> 13,000 microl(-1)). Based on retrospective analyses of 158 patients with CMML, we compared the presenting clinical and hematological features of both disorders and examined whether the refined classification is important in terms of prognosis. There were 81 patients with MDS-CMML and 77 patients with MPD-CMML. Median age of patients at diagnosis (70 versus 72 years) was not different. The sex ratio showed a preponderance of males in the MPD group (m:f; 2.1:1). Splenomegaly was more common in MPD-CMML (54 versus 30%; P = 0.002). With regard to laboratory findings, patients with MPD-CMML presented with significantly higher LDH values (medians 295 versus 231 U ml(-1); P = 0.008) and higher serum deoxythymidine kinase levels (medians 150 versus 41 U microl(-1); P = 0.0025). Except for white blood cell count (WBC), peripheral blood counts were not different. Median percentage of bone marrow blasts was 9% and cumulative survival rates were similar in both disorders. Two years after diagnosis, actuarial survival for patients with MPD-CMML was 33%, as compared to 50% for patients with MDS-CMML (P = 0.31). The probability of transformation to AML was higher in MDS-CMML (32 versus 17% after 5 years), but this difference also did not reach statistical significance. The survival of patients with MDS-CMML was similar to that of other MDS patients (RAEB) who had corresponding medullary blast counts. Using the Düsseldorf-score, we could define two risk groups within MDS-CMML with a median survial of 12 versus 40 months (P = 0.001). None of the known scoring systems could define risk groups within the MPD-CMML group. In summary, these data suggest that MDS-CMML and MPD-CMML are clinically distinguishing conditions, but the separation provides little prognostic information. Further studies are needed to clarify whether response to therapy is different in MDS-CMML and MPD-CMML.

Increasing incidence of myelodysplastic syndromes: real or fictitious?

Over the past 10-20 years, there has been a growing interest in the myelodysplastic syndromes (MDS). Due to difficulties of diagnosis, classification and case recording, the epidemiological features of MDS are still poorly defined. Recently, a number of cancer registries have published data on the regional occurrence of MDS, suggesting that MDS are much more common than previously thought. The crude incidence of MDS in these studies was 3.5-12.6 per 100,000 population per year. In people over the age of 70 years, incidence rates varied between 15 and 50 per 100,000 per year. Contrary to the assumption of most hematologists, cancer surveys usually failed to demonstrate a rising incidence of MDS. In those studies showing a significant increase in MDS, the rising number of cases was probably due to increased physician awareness and extended use of invasive diagnostic procedures in elderly people. Differences in incidence figures between regional studies may be attributed to several causes, including regional variations in disease incidence, small and ill-defined reference populations, bias due to patient referral patterns, varying intensity of diagnostic procedures and different observation periods. Because of the paucity of clinical symptoms and insignificance of morphological bone marrow changes particularly in early stage MDS, the currently available incidence figures are likely to underestimate the true incidence of MDS. Large-scale epidemiological studies are required for obtaining truly representative statistics on the incidence and prevalence of the MDS. In industrialized countries, a dramatic increase in these disorders can be expected over the next few decades due to the 'greying' of the population.

[Indications, technique and risks in bone marrow transplantation in adulthood]. / Indikationen, Durchführung und Risiken der Knochenmarktransplantation Im Erwachsenenalter.

The option of bone marrow transplantation (BMT) significantly improved prognosis of adult patients with hematologic malignancies aged less than 50 years. Allogeneic BMT using the marrow of an HLA-identical family member still provides the most effective method of BMT. Conventional indications for this form of BMT are chronic myeloid leukemia (CML), acute leukemias presenting with adverse risk factors, myelodysplastic syndromes and severe aplastic anemia. If performed early in the disease course (e.g. during the chronic phase of CML or first remission of acute leukemia and MDS) allogeneic BMT cures 50 to 60% of patients. About 20% die of therapy related complications, e.g. graft versus host disease (GvHD), fatal infections or venoocclusive disease of the liver (VOD) and about 20% of patients succumb to relapse of their hematologic disorder. 80% presenting with severe aplastic anemia can be cured, if allogeneic BMT is performed soon after diagnosis without previous immunosuppressive therapy and blood transfusions. BMT with the marrow of a matched unrelated donor or autologous BMT are increasingly used as alternative procedures. A rate of lethal complications as high as 50% hinders rapid extension of BMT with unrelated donors. Therefore, this form of BMT should be restricted to young patients with leukemias, who cannot achieve long-term remission with conventional chemotherapy (in case of acute leukemias) or alpha-interferon (in case of CML). Reconstitution of hematopoiesis is more rapid after peripheral blood stem cell transplantation (PBSCT) compared with autologous BMT. Therefore, PBSCT will replace autologous BMT in most cases. Most favourable results of PBSCT have been reported in patients with malignant lymphomas after relapse or inferior response to primary induction therapy. Due to the higher relapse rate autologous BMT is inferior to allogeneic BMT in leukemia patients. Trials are required to clarify the potential role of myeloablative therapy with stem cell support in the treatment of patients with solid tumors. Many of the preliminary results already published are unsatisfactory and data of larger trials are still lacking. Therefore, BMT or PBSCT cannot be recommended generally for the therapy of patients with solid tumors.