"Therapies for Myelodysplastic Syndrome Only Improve Survival in Distinct Patient Subgroups: Presented at MDS"
By Alison Palkhivala
FLORENCE, ITALY -- May 23, 2007 -- Treatments for myelodysplastic syndrome (MDS) only provide a survival benefit in certain subsets of patients, according to a matched-pair analysis presented here at the 9[th International Symposium on Myelodysplastic Syndromes (MDS).
To date, only MDS patients receiving best supportive care have been evaluated for prognosis, said presenter Katherin Nachtkamp, MD, department of haematology and oncology, Heinrich-Heine University, Düsseldorf, Germany.
It is therefore unclear whether new therapies improve survival or only serve to ameliorate haematological parameters and quality of life. To determine the prognostic impact of these therapies, Dr. Nachtkamp and colleagues performed a matched pair analysis on 3,125 patients from the Düsseldorf MDS registry, and evaluated antithymocyte globulin (ATG), thalidomide, valproic acid, low-dose arabinoside C (AraC), induction chemotherapy, and allogeneic stem cell transplantation (ASCT) compared with best supportive care.
Notably, prognosis among patients who received best supportive care did not change based on year of diagnosis, which ranged from 1970 to 2005. Survival was significantly longer among the 55 patients in the registry who received thalidomide, compared with best supportive care (33 vs 25 months, P =.0291).
Looking at patients based on their International Prognostic Scoring System (IPSS) scores revealed that a survival benefit with thalidomide was only evident in those with IPSS scores of 2 and 3 (31 vs 8 months, P =.0070).
Both treatment with ASCT (n = 39) and ATG (n = 17) improved overall survival in the groups receiving these therapies (40 vs 14 months, P =.0498 and 158 vs 61 months, P =.0447, respectively). ASCT was particularly effective in patients with IPSS scores of 2 or 3 (65 vs 8 months, P =.0017).
Valproic acid treatment (n = 76) was also associated with a longer survival time (48 vs 29 months, P =.0325) in the overall group, but was particularly effective in patients with refractory anaemia with excess blasts (RAEB) classification I and II, and RAEB in transition (48 vs 10 months, P =.0036).
Low-dose AraC (n = 65) only improved survival in patients with IPSS scores of 2 or 3 (18 vs 7 months, P =.0294), while induction chemotherapy (n = 172) only improved survival in patients with RAEB II and RAEB in transition who were under 60 years of age (22 vs 11 months, P =.0431)
"Treatment is not necessarily associated with an improvement in survival," Dr. Nachtkamp said. "A superior outcome in comparison with nontreated patients could only be shown in certain patient subgroups, such as high-risk MDS patients treated with thalidomide, AraC, or ASCT, and low-risk patients who were given AGT."
But she also warned, "The results of matched analyses should not be overinterpreted. It is an inferior methodology in comparison with phase 3 studies. In addition, we have to consider that it is easier to demonstrate a survival benefit in high-risk [compared with low-risk] patients."
Dr. Nachtkamp also noted that even if treatment does not affect overall survival, improvements in haematological parameters and quality of life remain good rationales for treating chronic conditions such as MDS.
[Presentation title: Influence of Different Treatment Strategies on the Prognosis of Patients With Myelodysplastic Syndromes (MDS). Abstract C014]
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