| Myelodysplastic syndromes (MDSs) are clonal disorders involving bone marrow stem cells and characterized by disorderly hematopoiesis, peripheral cytopenia and susceptibility to acute leukemias. Patients with myelodysplastic syndrome have short survival and high mortality rate, so it is important to recognize the indicators which can predict the prognosis. Cytogenetic changes may provide important prognostic information,. The purpose of this article is to study the disciplinarian of chromosome abnormalities and the relationship between chromosome abnormalities and prognostic in MDSs. 45 cases which were newly diagnosed MDS in our hospital from September 2000 to January 2004 were carried out cytogenetic analysis, shows: (1) Twenty-seven patients presented clonal chromosome abnormalities, rate of abnormality is 60%. There are 15 males and 12 females in the 27 patiens. Chromosome abnormalities rate in with MDSs pations at less than 60 ages is 59.6ï¼…,and at more than 60 ages is 62.5ï¼….(2) The abnormal chromosome include 1, 3, 5, 7, 8, 9, 11, 15, 16, 18, 20, 21. These abnormalities consist of deletions, trisomies, monosomies, translocations and complex structural anomalies. The proportion of patients with only numerical chromosome changes is 64%. (3) Cytogenetic changes were found in 13 patients with RA , RAS and 18 patients with RAEB or RAEBT. The incidences of complex chromosome abnormalities have no statistic significance in the two groups. (4) Patients with abnormal chromosome ran a greater risk of developing acut leukemia than those with normal karyotypes. Some Patients presented cytogenetic evolution following the transformation of myelodysplastic syndrome to acute myelogenous leukemia, they have a higher mortality rate. Two cases with t(8:21)(q22:q21) evolved acute myeloid leukemia-M2. (4) Patients with normal chromosome have median survival of 26.8 months, as compared with 8 months for those with cytogenetic changes. According to the criteria of international prognostic scoring system, we classified all the 45 patients into one low-risk category, two intermediate-risk categories(INT-1 and INT-2), and one high-risk category. The median survival is 866 days for those with INT-1, 491 days for those with INT-2, and 250 days for high-risk category. In the light of the above analysis, we can come to the following conclusions: (1)The rate of chromosome abnormalities is 60%. It has no relation between age, gender and chromosome abnormalities. (2)Multiple cytogenetic changes have been identified in MDSs, but the loss of chromosome is primary. (3)Patients with RAEB or RAEBT have a higher incidence of chromosome abnormalities and complex cytogenetic changes than patients with RA or RAS. (4) Patients with abnormal chromosome ran a greater risk of developing acut leukemia than those with normal karyotypes. Some Patients presented cytogenetic evolution following the transformation of myelodysplastic syndrome to acute myelogenous leukemia, they have a higher mortality rate. In some cases, AML with specific cytogenetic abnormalities, such as t(8:21)(q22:q21), may present with a low myeloblast count in the range lf an MDS.Despite low initial blast percentages, patients with these karyotypes should always be considered as having AML rather than an MDS. These patients shoud accept chemotherapy as soon as possible so that they can acquire complete response (CR) in early phase. (5)In MDSs, cytogenetic studies have important significance in prediction of survival. Patients with normal karyotypes do much better than those with chromosome abnormalities. So bone marrow cytogenetic studies should be performed in every case of suspected MDS.
|
PDF Full Text Request