Characteristics and prognostic factors of acute myeloid leukemia with t (8; 21) (q22; q22) / 中国实验血液学杂志

ABSTRACT

The translocation t (8; 21) (q22; q22) frequently associated with additional chromosomal aberrations is one of the most recurrent chromosomal abnormalities in AML. Clinically, this type of AML usually shows some specific characteristics and has a good response to chemotherapy with a high remission rate and a relatively long median survival. On the other hand, some reports also showed poor prognosis in AML patients with t (8; 21), and the associated bad-prognosis factors have not been strongly established to date. To investigate this issue and to further identify the related characteristics of t (8; 21) AML in China, 75 Chinese AML patients with t (8; 21) were retrospectively analyzed. They comprised 68 cases of M(2), five of M(4) and two of M(5) according to FAB classification. The results indicated that Auer rods were observed in 39 patients (52%) and marrow eosinophilia was detected in only 5 patients (6.7%). These patients showed high level of HLA-DR and CD34 expression, while CD19 was detected in only 13 patients (20.9%). Cytogenetically, 62.5% cases had additional chromosomal abnormalities, and the main associated recurrent additional abnormalities were loss of a sex chromosome (LOS), trisomy 4, del (9q) and trisomy 8. After conventional induction therapy, 62 patients attained complete remission (CR) resulting in the CR rate 82.7%. With a follow-up of 1 to 96 months, 19 cases relapsed at a median time of 10.5 months (range 3 to 42 months). The median overall survival was 20 months, and the estimated 5-year overall survival (OS) rate was 32.3%. In multivariate analyses of prognostic factors, karyotype, extramedullary leukemia, age and post-remission therapy were of prognostic value for OS. Patients with additional chromosomal anomalies had shorter survival compared to those with t (8; 21) only (P = 0.019), no matter which kind of additional karyotype it was. Extramedullary leukemia was an adverse prognostic factor (P = 0.012). Patients aged 15 years or less had a longer survival than those aged more than 15 years (P = 0.045). Patients accepted HSCT in post-remission therapy had better outcome compared to those with chemotherapy only. It is concluded that Chinese AML patients with t (8; 21) had some different characteristics as compared with patients from other countries, a relatively poor outcome was observed in our patients, especially in those with extramedullary leukemia or additional chromosomal abnormalities. HSCT should be recommended to t (8; 21) AML in China, especially to those with adverse prognostic factors.