Prognostic Analysis of Refractory Anemia in Adult Patients with Myelodysplasric Syndrome in China.

Several reports indicated a striking difference in age, chromosome abnormalities and prognosis between Western and Eastern MDS patients, even in the same subtype. The prognostic factors in Chinese MDS patients remain unclear. To investigate the prognostic factors and survival rate in Chinese cases with refractory anemia (RA) in adult MDS based on FAB classification, and to evaluate the applicability of international prognostic scoring system (IPSS) for Chinese MDS-RA patients by comparing with the clinical features of Western cases, Three hundred and seven MDS-RA cases were registered and followed-up in Shanghai, Suzhou and Beijing from 1995 to 2006. The longest follow-up duration was 103 months, and the median follow-up duration was 26.7 months. Kaplan-Meier curve, Log-rank and COX regression model were used to analyze the prognostic factors and survival rate. The median age of 307 MDS-RA cases was 52 years. The frequency of 2 or 3 lineage cytopenias was 85.6%. Abnormal karyotype occurred in 35.7% of all MDS-RA patients. By IPSS cytogenetic risk groups, 165 cases (70.2%) were in the good IPSS cytogenetic subgroup, 44 cases (18.7%) in the intermediate IPSS cytogenetic subgroup and 26 cases (11.1%) in the poor IPSS cytogenetic subgroup. According to IPSS, 20 cases (8.5%) were categorized as low risk, 195 cases (83.0%) as intermediate–I risk and 20 cases (8.5%) as intermediate–II risk. The 1–year, 2–year, 3–year, 4–year and 5–year survival rate were 90.8%, 85.7%, 82.9%, 74.9% and 71.2%, respectively. Fifteen cases (4.9%) transformed to acute myeloid leukemia and the median transformation time was 15.9 months (range 3–102 months). Lower white blood cells count (<1.5 × 10⁹/L), platelet count (<30 × 10⁹/L) and cytogenetic abnormalities were identified as independent prognostic factors by multivariate analysis, while the age (≥65 years), hemoglobin level(<60g/L), IPSS cytogenetic subgroup and IPSS risk subgroup were not independent prognostic factors associated with survival time by COX regression analysis. In summary, Chinese patients were younger and had lower incidence of cytogenetic abnormalities and more severe cytopenias than that of the Western patients. However, the Chinese patients have more favorable prognosis than Western patients do. WBC count, platelet count and karyotype are major prognostic factors for prediction of survival and can be helpful in identifying patients with different prognosis and consequently designing the optimal therapeutic strategies. The present IPSS scores based on conditions of western patients may not be perfectly applicable to MDS-RA patients in Asia and need to be modified.