Biologic Features and Clinical Outcomes According to Age Groups In Myelodysplastic Syndrome

Abstract 4963

Myelodysplastic syndrome (MDS) is a disease of the elderly, but can also affect younger people. Age is known to be an important prognostic factor in MDS but age variable is not included in most prognostic scoring systems because it is not thought as a disease-related variable. Many reports have showed that MDS is seen one to two decades earlier in Far Eastern countries than Western countries. We retrospectively investigated the differences in biologic features and clinical outcomes according to different age groups in Korean patients with MDS. Primary end points of our study were overall survival (OS) and progression-free survival (PFS). PFS was defined as time from diagnosis to AML progression or death. About one third of the patients received intensive treatment including chemotherapy, hypomethylating treatment or hematopoietic cell transplantation. Therefore, all survival data were censored at the start of intensive treatment to eliminate the influence of the treatments on clinical outcomes. A total of 403 patients, 248 males and 155 females, were included in this study. Median age was 54 years. We divided the patients into three age groups: ≤50 years (n=181), 51 to 60 (n=81), and over 60 (n=141). Baseline biologic features were significantly different according to three age groups: with increasing age, more male preponderance (P=0.009), more BM blast percentage (P<0.001), more advanced WHO subtype (P<0.001), higher proportion of high risk cytogenetic features (P=0.052; ≤60 vs. >60, P=0.011), poorer ECOG performance status (P=0.004), higher IPSS risk group (P=0.019). Five-year survival probabilities were significantly different according to age groups (≤ 50 vs. 51–60 vs. > 60; OS, 66.8% vs. 28.5% vs. 12.2%, P<0001; PFS, 58.5% vs. 37.9% vs. 12.3%, P<0.001). Survivals were also significantly different according to age groups in both IPSS Low/INT-1 (P<0.001 for OS, P=0.001 for PFS) and IPSS INT-2/High risk group (P=0.026 for OS, P=0.069 for PFS). Cox proportional hazards models also demonstrated that age group was an independent prognostic factor for survivals: ≤ 50 vs. 51–60 and > 60; OS, RR 2.3 (P=0.037) and RR 4.6 (P<0.001); PFS, RR 1.3 (P=0.449) and RR 2.0 (P=0.012).