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Originally published as JCO Early Release 10.1200/JCO.2007.11.9214 on April 14 2008 © 2008 American Society of Clinical Oncology. Factors Affecting Response and Survival in Patients With Myelodysplasia Treated With Immunosuppressive Therapy
From the National Heart, Lung and Blood Institute, Division of Intramural Research, Hematology Branch, Bethesda, MD; and Hematology Division, Stanford University Cancer Center, Stanford, CA Corresponding author: Elaine M. Sloand, National Heart, Lung and Blood Institute, 9000 Rockville Pike, Bldg 10, CRC 5230, Bethesda, MD 20892; e-mail: sloande{at}nhlbi.nih.gov
Purpose: Marrow failure in some patients with myelodysplastic syndrome (MDS) responds to immunosuppressive treatment (IST), but long-term outcome after IST has not been described. We evaluated patients with MDS treated with IST at our institution to determine their clinical course compared with a comparable supportive care only group. Patients and Methods: One hundred twenty-nine patients with MDS received IST with a median follow-up of 3.0 years (range, 0.03 to 11.3 years), using antithymocyte globulin (ATG) or cyclosporine (CsA) in combination or singly. Variables affecting response and survival were studied and outcomes were compared with those of 816 patients with MDS reported to the International Myelodysplasia Risk Analysis Workshop (IMRAW) who received only supportive care. Results: Thirty-nine (30%) of 129 patients receiving IST responded either completely or partially: 18 (24%) of 74 patients responded to ATG, 20 (48%) of 42 patients responded to ATG plus CsA, and one (8%) of 13 patients responded to CsA. Thirty-one percent (12 of 39) of the responses were complete, resulting in transfusion independence and near-normal blood counts. In multivariate analysis, younger age was the most significant factor favoring response to therapy. Other favorable factors affecting response were HLA-DR15 positivity and combination ATG plus CsA treatment (P = .001 and P = .048, respectively). In multivariate analysis of the combined IMRAW and IST cohorts, younger age, treatment with IST, and intermediate or low International Prognostic Scoring System score significantly favored survival. Conclusion: IST produced significant improvement in the pancytopenia of a substantial proportion of patients with MDS and was associated with improved overall and progression-free survival, especially in younger individuals with lower-risk disease.
Myelodysplastic syndromes (MDS) include a group of disorders that vary widely in clinical presentation and severity.1,2 Typically, patients with MDS are older adults with comorbidities.3 Death from MDS is due to progression to acute leukemia or to the consequences of cytopenias.4 The International Prognostic Scoring System (IPSS) can predict survival based on clinical, hematologic, and karyotypic features.5 No treatment other than allogeneic stem-cell transplantation6 has yet been shown to prolong survival, although for some patients with MDS, hematopoietic growth factors,7 decitabine,8 and lenalidomide9 may improve cytopenias, and 5-azacytidine may reduce transfusion requirements, delay the time to leukemic transformation, and improve quality of life when compared with supportive care.10,11 Chemotherapy has a limited role in the management of leukemic progression,12 and autologous stem-cell transplantation does not prolong relapse-free survival.13 The concept that an immune-mediated response directed against hematopoietic cells can cause failure of the bone marrow leading to pancytopenia arose from early experience with bone marrow transplantation to treat severe aplastic anemia, in which some nonengrafting patients developed autologous hematologic recovery. Several investigators subsequently used antithymocyte globulin (ATG) to treat the bone marrow failure accompanying hypoplastic MDS with some success.14,15 Immunosuppressive therapy (IST) can benefit patients with MDS regardless of cellularity.16-23 We previously described hematologic responses, including transfusion independence, in 21 of 61 patients with MDS given ATG.23 We subsequently developed a scoring system to predict response to IST based on the patient's age, duration of RBC transfusion dependence, and presence of an HLA-DR15 allele24 (designated the IST response probability score [ISTRPS]). Although IST can improve cytopenias in MDS, the impact of IST on survival and leukemic progression in both responders and nonresponders has not been studied. Here we examine the response rates and long-term survival of patients treated with IST and compare the outcome of IST responders and nonresponders with that of a control population of 816 patients drawn from the International Myelodysplasia Risk Analysis Workshop (IMRAW) database who received neither IST nor cytotoxic drugs.5
Patients Patients with MDS, classified according to French-American-British criteria25 as refractory anemia, refractory anemia with ringed sideroblasts, or refractory anemia with excess blasts, were enrolled to receive equine ATG (Pharmacia, Kalamazoo, MI), ATG plus cyclosporine (CsA), or CsA alone, in sequential protocols 00-H-0169, 04-H-0026, and 95-H-0189 approved by the institutional review board of the National Heart, Lung and Blood Institute. Patients included in the trials were diagnosed with MDS between 1971 and 2003. The first trial treated 62 consecutive patients with ATG alone. The second trial randomly assigned 23 patients to receive either ATG or CsA, and the third trial treated consecutive patients with ATG plus CsA. Patients who received IST in this study comprised 69 patients previously reported24 and an additional 60 patients. We compared survival with a group of 816 patients with MDS reported by the IMRAW5 diagnosed between 1973 and 1994 analyzed for survival (816 patients) and freedom from acute myeloid leukemia (AML) evolution (759 patients).
Eligibility for IST
Response Criteria Blood counts were obtained weekly during the study. Response was assessed by at least three serial measurements obtained 1 month apart. Transfusion independence was defined as no transfusion requirement for a 3-month period. Improvement in the transfusion requirement was a secondary end point, defined as a halving of the number of transfusions received in a 2-month period assessed 6 months after completion of treatment. Patients were followed up yearly to assess the durability of response, disease progression, and survival. For comparability with patients in the IMRAW database,5 leukemia was defined as more than 30% blasts in the bone marrow. Patients not surviving or those receiving alternative treatment, such as stem-cell transplantation for disease progression, were classified as nonresponders.
Statistical Methods
Patient Selection All 129 patients enrolled had de novo MDS without preceding aplastic anemia or prior chemotherapy. By IPSS criteria,5 16 patients were considered low risk, 94 patients were considered intermediate-1 (int-1), 13 patients were considered int-2, and six patients were considered high risk. Median follow-up was 2.9 years (range, 0.03 to 11.3 years). Patient characteristics are listed in Table 1. Time from diagnosis to treatment ranged from 0 to 197 months (median, 19 months). Seventy-four patients received equine ATG, 42 patients received a combination of ATG and CsA (maintaining CsA levels > 100 ng/mL for up to 6 months), and 13 patients received CsA alone on the same schedule.
Response to IST Of the 129 patients receiving a single course of IST, 39 patients (30%) experienced either complete or partial response; 18 (24%) of 74 patients (95% CI, 14% to 34%) responded to ATG, 20 (45%) of 42 patients (95% CI, 32% to 63%) responded to ATG plus CsA (P = .01), and one (8%) of 13 patients responded to CsA. Thirty-one percent (12 of 39 patients; 95% CI, 16% to 46%) of the responses were complete, resulting in near-normal blood counts and transfusion independence; 32 (82%) of 39 (95% CI, 70% to 94%) of the responders had either a bi-lineage or trilineage responses. Of the partial responders, all but one became transfusion independent; this patient had paroxysmal nocturnal hemoglobinuria (PNH) with hemolysis and required eventual transplantation. One hundred twenty-two patients were RBC transfusion dependent before IST. Of these, 31% (95% CI, 23% to 39%) responded to IST at a median time of 4 months. Five responders but no nonresponders were re-treated with immunosuppression. Responses were the same when the response classification of the International Working Group criteria was applied (data not shown).26 Twenty-four (62%) of the 39 (95% CI, 46% to 77%) responders had neutrophil responses; 34 (87%) of the 39 responders (95% CI, 76% to 98%) had RBC responses, and 24 (62%) of the 39 responders (95% CI, 46% to 77%) had platelet responses. For int-1 IPSS patients, the response rate to ATG plus CsA was superior to that of ATG alone: 54% versus 29% (P = .004). The difference between treatments was also significant in multivariate analysis (P = .048; Table 2). The total number of int-1 responders for patients 60 years was 28 (51%) of 54 versus six (15%) of 39 in patients older than 60 years (P < .001). Three of thirteen int-2 patients responded to IST, including three of five patients 60 years versus 0 of eight patients older than 60 years. Univariate analysis showed a small contribution of RBC transfusion duration on response rate and that the relationship between age was a continuous variable affecting probability of response. In multivariate analysis, age as a continuous variable and the presence of the DR15 allele were the most significant factors affecting response (P < .001 and P = .002, respectively; Table 2). There was no association of cellularity, PNH clone or absolute neutrophil count, sex, or duration of transfusion dependence with response (P = .543, .833, .978, and .116, respectively).
Treatment Toxicity Twelve patients required temporary admission to the intensive care unit during ATG treatment. Six patients did not complete the 4 days of ATG treatment: three developed shaking chills, two had hypotension associated with shaking chills, and one died from alveolar hemorrhage associated with leukemic pulmonary infiltrates.
Outcome After IST Given differences in follow-up care and variation in the frequency of blood count monitoring, it was not possible to assign exact dates of relapse. Relapse after IST was therefore defined as the date of reinitiation of therapy (transfusions, cytokines, IST [including CsA alone for patients treated with ATG/CsA], transplantation, or other drugs used to treat MDS). Four relapses occurred in the ATG plus CsA group (after discontinuation of CsA), whereas nine relapses occurred in the ATG-only group. The median duration of responses for the responding individuals was 3 years (range, 3 months to 10 years). Among the 12 patients with complete responses, four patients experienced relapse within the first year, but all responded to reinitiation of immunosuppression; of these, only two patients required reinitiation of CsA. Three of these patients remain in remission without further treatment at a median follow-up of 6.2 years. Two patients (both with trisomy 8) require continued low-dose CsA. Of the 27 partial responders, nine experienced relapse; three patients underwent transplantation and three patients responded to an additional course of IST. Three patients were treated long-term with CsA and remain in remission. Median relapse-free survival was greater than 10.5 years. Results of long-term follow-up of the IST cohort are listed in Table 3.
Comparison of Outcome in IST and IMRAW Cohorts Multivariate Cox regression models were used to analyze the combined IMRAW-IST data for survival from enrollment into both study and time to develop leukemia. Continuous measurements were used for age, absolute neutrophil count, and platelet counts. Discrete covariates were sex, study cohort (IMRAW or IST), IPSS categories (low, int-1, int-2, and high), and marrow blast categories (0% to 5%, > 5% to 10%, and > 10%). Cytogenetics were grouped as follows: 1 = normal and 20q-; 2 = 5q-; 3 = chromosome 7 abnormalities and complex chromosome abnormalities; 4 = other cytogenetic abnormalities; 5 = trisomy 8. Variables affecting survival were age, number of blasts, female sex, cytopenias, cytogenetics, and treatment with IST. The negative regression coefficient and less than 1.00 relative risk for IST indicated that IST was associated with better survival after adjusting these covariates (Table 4). Benefit from IST became more significant in multivariate analysis of patients 60 years of age; conversely, there was no significant survival benefit for IST patients older than 60 years of age when compared with the IMRAW cohort (P = .10). IPSS score and age emerged as major independent factors affecting survival for both the IST and the IMRAW cohorts. We compared outcomes for the two cohorts in the subset of int-1 patients aged 60 years and older than 60 years. For the int-1 patients 60 years, survival of the 55 IST patients was longer than for the 89 IMRAW patients (median > 8.1 v 5.2 years; P = .001; Fig 1). Similarly, the proportion of int-1 patients 60 years developing AML was lower in the IST versus IMRAW patient cohort (time for 25% of cohort to develop AML was 6.9 years for IMRAW v > 8.2 years of the IST group; P = .002). When used as a continuous variable, age was shown to be highly predictive for response to IST (Fig 2; P < .001). In contrast, duration of RBC transfusion need was not.
Our data demonstrated clinical benefit of IST for a substantial proportion of patients with MDS. Of the criteria previously identified to predict IST response, age emerged as the strongest factor for predicting survival after IST: responders predominated in the group of 55 patients 60 years of age. Improved responses and clinical outcomes also predominated in the IPSS int-1 patient subset. This translated into survival benefit for responders who also had a 96% leukemic progression-free survival at a median follow-up of 6 years. Patients treated with ATG plus CsA had superior response rates compared with patients treated with ATG alone, although there were no survival differences between these groups. Neither marrow cellularity30 nor the presence of a PNH clone31 influenced the probability of response to IST. A recent study of 96 patients with MDS indicated that hypocellularity and low IPSS score predicted response to immunosuppression.32 Others have shown that hypocellular marrow positively affects response33 as well. Differences in cohort composition as well as differences in pathologic discrimination of aplastic anemia and MDS may have accounted for these differing findings.
In the absence of a prospective study randomly assigning patients with MDS to receive IST or conventional support, it has not been possible to ascertain the overall impact of IST on survival and leukemia progression. Thus the IMRAW patient cohort was used as an untreated historical control group. Patients in the IMRAW group were studied from time of diagnosis, whereas patients in the National Institutes of Health (NIH) group were studied from time of treatment. This could have introduced a bias, as healthier patients may have survived longer to be entered into the clinical trial. However, the time from diagnosis to treatment averaged 1 year in the NIH study, and survivals between IST and conservatively treated patients were so great that it is unlikely to have accounted for the results. Therefore, we analyzed factors affecting outcome in the combined NIH and IMRAW cohorts. Age, cytopenias, number of blasts, and treatment with IST were major variables affecting survival. It was previously noted that age older than 60 years was a major discriminating factor for survival in the IMRAW cohort.5 In this study, IST patients Although the mechanism whereby younger patients with MDS benefit from IST is not clear, it is possible that powerful immunosuppressive effects causing myelosuppression dominate MDS occurring in younger patients, whereas MDS developing in older patients may be predominantly a stem cell abnormality predisposing to cytopenias and leukemia without the autoimmune component. Older patients may also have a smaller marrow reserve, diminishing the chance of hematologic response to IST. Many studies have confirmed a beneficial effect of IST on the cytopenias of patients with MDS.20-23,34,35 However, there are no prior reports on the durability of response and survival after IST. Our data indicate that improved survival in IST responders is associated with a sustained improvement in cytopenias and a lower risk of leukemic progression. Importantly, there was no evidence that nonresponders to IST were adversely affected by more rapid progression to leukemia, because outcomes for the older than 60 years age group (containing predominantly IST nonresponders) were comparable between IST and IMRAW patients. Our findings are of clinical importance because they indicate that a portion (mainly younger int-1 patients) of individuals with MDS benefit from IST, with sustained improvement of cytopenias and improved survival and freedom from AML evolution. Prospective clinical trials are warranted to further clarify the role of IST in MDS.
The author(s) indicated no potential conflicts of interest.
Conception and design: Elaine M. Sloand, Neal Young, John Barrett Provision of study materials or patients: Elaine M. Sloand, Neal Young, John Barrett Collection and assembly of data: Elaine M. Sloand, Peter Greenberg, Neal Young, John Barrett Data analysis and interpretation: Elaine M. Sloand, Colin O. Wu, Peter Greenberg, Neal Young, John Barrett Manuscript writing: Elaine M. Sloand, Colin O. Wu, Peter Greenberg, Neal Young, John Barrett Final approval of manuscript: Elaine M. Sloand, Colin O. Wu, Peter Greenberg, Neal Young, John Barrett
We thank the International Myelodysplasia Risk Analysis Workshop for providing the database with clinical information on their patients.
published online ahead of print at www.jco.org on April 14, 2008 Authors' disclosures of potential conflicts of interest and author contributions are found at the end of this article.
1. List AF, Vardiman J, Issa JP, et al: Myelodysplastic syndromes. Hematology Am Soc Hematol Educ Program 297-317, 2004 2. Barrett J, Sloand EM, Young N: Immunologic mechanisms and gene expression patterns in myelodysplastic syndromes, in Greenberg PL (ed): Myelodysplastic Syndromes: Clinical and Biological Advances. Cambridge, England, Cambridge University Press, 2006, pp 147-171 3. Toyama K, Ohyashiki K, Yoshida Y, et al: Clinical implications of chromosomal abnormalities in 401 patients with myelodysplastic syndromes: A multicentric study in Japan. Leukemia 7:499-508, 1993[Medline] 4. Guralnik JM, Eisenstaedt RS, Ferrucci L, et al: Prevalence of anemia in persons 65 years and older in the United States: Evidence for a high rate of unexplained anemia. Blood 104:2263-2268, 2004 5. Greenberg P, Cox C, LeBeau MM, et al: International scoring system for evaluating prognosis in myelodysplastic syndromes. Blood 89:2079-2088, 1997 6. Wong R, Shahjahan M, Wang X, et al: Prognostic factors for outcomes of patients with refractory or relapsed acute myelogenous leukemia or myelodysplastic syndromes undergoing allogeneic progenitor cell transplantation. Biol Blood Marrow Transplant 11:108-114, 2005[Medline] 7. Jädersten M, Montgomery SM, Dybedal I, et al: Long-term outcome of treatment of anemia in MDS with erythropoietin and G-CSF. Blood 106:803-811, 2005 8. van den Bosch J, Lübbert M, Verhoef G, et al: The effects of 5-aza-2'-deoxycytidine (Decitabine) on the platelet count in patients with intermediate and high-risk myelodysplastic syndromes. Leuk Res 28:785-790, 2004[CrossRef][Medline] 9. List A, Kurtin S, Roe DJ, et al: Efficacy of lenalidomide in myelodysplastic syndromes. N Engl J Med 352:549-557, 2005 10. Silverman LR, Demakos EP, Peterson BL, et al: Randomized controlled trial of azacitidine in patients with the myelodysplastic syndrome: A study of the cancer and leukemia group B. J Clin Oncol 20:2429-2440, 2002 11. Silverman LR: DNA methyltransferase inhibitors in myelodysplastic syndrome. Best Pract Res Clin Haematol 17:585-594, 2004[Medline] 12. Estey EH: Current challenges in therapy of myelodysplastic syndromes. Curr Opin Hematol 10:60-67, 2003[CrossRef][Medline] 13. de Witte T, Suciu S, Verhoef G, et al: Intensive chemotherapy followed by allogeneic or autologous stem cell transplantation for patients with myelodysplastic syndromes (MDSs) and acute myeloid leukemia following MDS. Blood 98:2326-2331, 2001 14. Biesma DH, van den Tweel JG, Verdonck LF: Immunosuppressive therapy for hypoplastic myelodysplastic syndrome. Cancer 79:1548-1551, 1997[CrossRef][Medline] 15. Tichelli A, Gratwohl A, Wuersch A, et al: Antilymphocyte globulin for myelodysplastic syndrome. Br J Haematol 68:139-140, 1988[Medline] 16. Asano Y, Maeda M, Uchida N, et al: Immunosuppressive therapy for patients with refractory anemia. Ann Hematol 80:634-638, 2001[CrossRef][Medline] 17. Barrett AJ, Molldrem JJ, Saunthrajarian Y, et al: Prolonged transfusion independence and disease stability in patients with myelodysplastic syndrome (MDS) responding to antithymocyte glogulin (ATG). Blood 10:713a, 1998 (suppl, abstr) 18. Molldrem J, Caples M, Mavroudis D, et al: Antithymocyte globulin (ATG) abrogates cytopenias in patients with myelodysplastic syndrome. Br J Haematol 99:699-705, 1997[CrossRef][Medline] 19. Steensma DP, Dispenzieri A, Moore SB, et al: Antithymocyte globulin has limited efficacy and substantial toxicity in unselected anemic patients with myelodysplastic syndrome. Blood 101:2156-2158, 2003 20. Killick SB, Mufti G, Cavenagh JD, et al: A pilot study of antithymocyte globulin (ATG) in the treatment of patients with low-risk myelodysplasia. Br J Haematol 120:679-684, 2003[CrossRef][Medline] 21. Yazji S, Giles FJ, Tsimberidou AM, et al: Antithymocyte globulin (ATG)-based therapy in patients with myelodysplastic syndromes. Leukemia 17:2101-2106, 2003[CrossRef][Medline] 22. Aivado M, Rong A, Stadler M, et al: Favourable response to antithymocyte or antilymphocyte globulin in low-risk myelodysplastic syndrome patients with a non-clonal pattern of X-chromosome inactivation in bone marrow cells. Eur J Haematol 68:210-216, 2002[CrossRef][Medline] 23. Molldrem JJ, Leifer E, Bahceci E, et al: Antithymocyte globulin for treatment of the bone marrow failure associated with myelodysplastic syndromes. Ann Intern Med 137:156-163, 2002 24. Saunthararajah Y, Nakamura R, Wesley R, et al: A simple method to predict response to immunosuppressive therapy in patients with myelodysplastic syndrome. Blood 102:3025-3027, 2003 25. Bennett JM, Catovsky D, Daniel MT, et al: Proposals for the classification of chronic (mature) B and T lymphoid leukaemias: French-American-British (FAB) Cooperative Group. J Clin Pathol 42:567-584, 1989 26. Cheson BD, Bennett JM, Kantarjian H, et al: Report of an international working group to standardize response criteria for myelodysplastic syndromes. Blood 96:3671-3674, 2000 27. Cheson BD, Greenberg PL, Bennett JM, et al: Clinical application and proposal for modification of the International Working Group (IWG) response criteria in myelodysplasia. Blood 108:419-425, 2006 28. Therneau TM, Li H: Computing the Cox model for case cohort designs. Lifetime Data Anal 5:99-112, 1999[CrossRef][Medline] 29. Fisher LD, Lin DY: Time-dependent covariates in the Cox proportional-hazards regression model. Annu Rev Public Health 20:145-157, 1999[CrossRef][Medline] 30. Cazzola M, Malcovati L: Myelodysplastic syndromes: Coping with ineffective hematopoiesis. N Engl J Med 352:536-538, 2005 31. Dunn DE, Tanawattanacharoen P, Boccuni P, et al: Paroxysmal nocturnal hemoglobinuria cells in patients with bone marrow failure syndromes. Ann Intern Med 131:401-408, 1999 32. Lim ZY, Killick S, Germing U, et al: Low IPSS score and bone marrow hypocellularity in MDS patients predict hematological responses to antithymocyte globulin. Leukemia 21:1436-1441, 2007[CrossRef][Medline] 33. Yue G, Hao S, Fadare O, et al: Hypocellularity in myelodysplastic syndrome is an independent factor which predicts a favorable outcome. Leuk Res 32:553-558, 2008[CrossRef][Medline] 34. Stadler M, Germing U, Kliche KO, et al: A prospective, randomised, phase II study of horse antithymocyte globulin vs rabbit antithymocyte globulin as immune-modulating therapy in patients with low-risk myelodysplastic syndromes. Leukemia 18:460-465, 2004[CrossRef][Medline] 35. Broliden PA, Dahl IM, Hast R, et al: Antithymocyte globulin and cyclosporine A as combination therapy for low-risk non-sideroblastic myelodysplastic syndromes. Haematologica 91:667-670, 2006 Submitted May 9, 2007; accepted January 25, 2008. This article has been cited by other articles:
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Copyright © 2008 by the American Society of Clinical Oncology, Online ISSN: 1527-7755. Print ISSN: 0732-183X
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