Intensive therapy for high-risk myelodysplastic syndromes and the biological significance of karyotype abnormalities

The yin-yang of immunity: Immune dysregulation in myelodysplastic syndrome with different risk stratification

Myelodysplastic syndrome (MDS) is a heterogeneous group of myeloid clonal diseases with diverse clinical courses, and immune dysregulation plays an important role in the pathogenesis of MDS. However, immune dysregulation is complex and heterogeneous in the development of MDS. Lower-risk MDS (LR-MDS) is mainly characterized by immune hyperfunction and increased apoptosis, and the immunosuppressive therapy shows a good response. Instead, higher-risk MDS (HR-MDS) is characterized by immune suppression and immune escape, and the immune activation therapy may improve the survival of HR-MDS. Furthermore, the immune dysregulation of some MDS changes dynamically which is characterized by the coexistence and mutual transformation of immune hyperfunction and immune suppression. Taken together, the authors think that the immune dysregulation in MDS with different risk stratification can be summarized by an advanced philosophical thought “Yin-Yang theory” in ancient China, meaning that the opposing forces may actually be interdependent and interconvertible. Clarifying the mechanism of immune dysregulation in MDS with different risk stratification can provide the new basis for diagnosis and clinical treatment. This review focuses on the manifestations and roles of immune dysregulation in the different risk MDS, and summarizes the latest progress of immunotherapy in MDS.

Cytogenetic aspects of adult primary myelodysplastic syndromes: Clinical implications

Myelodysplastic syndrome (MDS) is a heterogeneous disease from the clinical, biological and morphological point of view. The pathogenesis of MDS is not well established and it appears to occur complex changes in the stem cell biology. Clonal chromosomal aberrations are found in 30-50% of primary MDS and no specific cytogenetic abnormality has as yet been defined. The chromosomal abnormalities are predominantly characterized by partial/total chromosomal losses or chromosomal gains. These chromosomal abnormalities include mainly -5/del(5q), -7/del(7q), del(11q), del(12p), del(20q), -Y, and +8. The role of cytogenetic analysis in the diagnosis, prognosis, taking treatment decisions and follow up of patients with MDS has been clearly defined. Despite its difficulties in obtaining for analysis high quality metaphases conventional cytogenetics continues to be the basic technique for cytogenetic evaluation of a MDS patient. Other molecular cytogenetic methods have been shown to be complementary, without replacing the information obtained with this technique. Further investigations with both conventional and molecular cytogenetics in relation to clinical features as well as other molecular methods will undoubtedly contribute to improve understanding of the underlying genetic events responsible for the development and evolution of MDS leading to more accurate classification and management of MDS patients.

Treatment of pediatric myelodysplastic syndromes and juvenile myelomonocytic leukemia: the Brazilian experience in the past decade

BACKGROUND

Therapy strategies for myelodysplastic syndromes (MDS) and juvenile myelomonocytic leukemia (JMML) vary considerably.

OBJECTIVE

To review the treatment of Brazilian children who were diagnosed with MDS or JMML in the past decade and reported to the Brazilian Cooperative Group on Pediatric Myelodysplastic Syndromes (BCG-MDS-PED).

RESULTS

Of 173 children reported to the BCG-MDS-PED from January 1997 to January 2003 with a suspected diagnosis of MDS or JMML, 91 had the diagnosis confirmed after central review of the bone marrow aspirate and biopsy. Information on previous treatments was available for 78 MDS/JMML patients. Treatment varied from different schedules of low-dose (14%) and standard-dose chemotherapy (50%), granulocyte-colony-stimulating factor (G-CSF 7%), interferon (5%), steroids (2%) and erythropoietin (2%) to allogeneic stem-cell transplantation (SCT) (14%). No survival advantage could be demonstrated based on Hasle's classification or based on treatment.

CONCLUSION

This report reflects the current practice in treating Brazilian children with MDS/JMML without specific Cooperative Group guidelines. Treatment modalities were very heterogeneous. The strategies for implementing a national protocol should consider international guidelines and focus on local experience and available resources.

Thalidomide produces transfusion independence in long-standing refractory anemias of patients with myelodysplastic syndromes

Thalidomide was administered to 83 patients with myelodysplastic syndrome (MDS), starting at 100 mg by mouth daily and increasing to 400 mg as tolerated. Thirty-two patients stopped therapy before 12 weeks (minimum period for response evaluation), and 51 completed 12 weeks of therapy. International Working Group response criteria for MDS were used to evaluate responses. Intent-to-treat (ITT) analysis classified all off-study patients as nonresponders. Off-study patients belonged to a higher risk category (P =.002) and had a higher percentage of blasts in their pretherapy bone marrow than patients who completed 12 weeks of therapy (P =.003). No cytogenetic or complete responses were seen, but 16 patients showed hematologic improvement, with 10 previously transfusion-dependent patients becoming transfusion independent. Responders had lower pretherapy blasts (P =.016), a lower duration of pretherapy platelet transfusions (P =.013), and higher pretherapy platelets (P =.003). Among responders, 9 had refractory anemia (RA); 5 had RA with ringed sideroblasts; and 2 had RA with excess blasts. By ITT analysis, 19% of patients (16 of 83) responded, and when only evaluable patients were analyzed, 31% (16 of 51) responded. It was concluded that thalidomide, as a single agent, is effective in improving cytopenias of some MDS patients, especially those who present without excess blasts. (Blood. 2001;98:958-965)

Patients with myelodysplastic syndromes benefit from palliative therapy with amifostine, pentoxifylline, and ciprofloxacin with or without dexamethasone

Thirty-five patients with myelodysplastic syndrome (MDS) were registered on protocol MDS 96-02 and were receiving continuous therapy with pentoxifylline 800 mg 3 times a day and ciprofloxacin 500 mg twice a day by mouth; dexamethasone was added to the regimen for the partial responders and the nonresponders after 12 weeks at a dose of 4 mg by mouth every morning for 4 weeks. Amifostine was administered intravenously 3 times a week at 3 dose levels (200 mg/M2, 300 mg/M2, and 400 mg/M2) to cohorts of 10 patients each. Therapy has been continued for 1 year in responders. Twenty-nine have completed at least 12 weeks of therapy and are available for response evaluation. Of the 21 men and 8 women (median age, 67 years), 20 had refractory anemia (RA), 3 had RA with ringed sideroblasts (RARS), 5 had RA with excess blasts (RAEB), and 1 had chronic myelomonocytic leukemia (CMMoL). Five had secondary MDS. No differences were noted in response rates among the 3 dose levels. Seven patients did not respond at all, and 22 showed an improvement in cytopenias (76%). Three had a triple lineage response, 10 had a double lineage response, and 9 had a single lineage response (8 of 9 in absolute neutrophil count [ANC] and 1 had more than a 50% reduction in packed red blood cell transfusions). Fifteen patients responded only after the addition of dexamethasone, whereas 7 responded before. When examined by lineage, 19 of 22 showed improved ANC, 11 of 22 demonstrated more than 50% reduction in blood transfusions, improved Hb levels, or both, and 7 of 22 showed improvement in platelet counts. Interestingly, the responses were frequently slow to appear, and continued improvement in counts was seen up to 12 months of therapy and beyond. This study supports the feasibility of treating patients with MDS with the unique approach of cytoprotection and anticytokine therapies as well as the principle that prolonged commitment to treatment is desirable when noncytotoxic agents are administered.