Chronic myeloid leukemia and interferon-alpha: a study of complete cytogenetic responders
F Bonifazi, A de Vivo, G Rosti, F Guilhot, J Guilhot, E Trabacchi, R Hehlmann, A Hochhaus, P C Shepherd, J L Steegmann, H C Kluin-Nelemans, J Thaler, B Simonsson, A Louwagie, J Reiffers, F X Mahon, E Montefusco, G Alimena, J Hasford, S Richards, G Saglio, N Testoni, G Martinelli, S Tura, M Baccarani, Europena Study Group on Interferon in Chronic Myeloid Leukemia, Italian Cooperative Study Group on CML, France Intergroup of CML, German CML Study Group, UK Medical Research Council Working Party on CML, Spanish CML Study Group, Australian CML Study Group, Swedish CML Study Group, F Bonifazi, A de Vivo, G Rosti, F Guilhot, J Guilhot, E Trabacchi, R Hehlmann, A Hochhaus, P C Shepherd, J L Steegmann, H C Kluin-Nelemans, J Thaler, B Simonsson, A Louwagie, J Reiffers, F X Mahon, E Montefusco, G Alimena, J Hasford, S Richards, G Saglio, N Testoni, G Martinelli, S Tura, M Baccarani, Europena Study Group on Interferon in Chronic Myeloid Leukemia, Italian Cooperative Study Group on CML, France Intergroup of CML, German CML Study Group, UK Medical Research Council Working Party on CML, Spanish CML Study Group, Australian CML Study Group, Swedish CML Study Group
Abstract
Achieving a complete cytogenetic response (CCgR) is a major target in the treatment of chronic myeloid leukemia (CML) with interferon-alpha (IFN-alpha), but CCgRs are rare. The mean CCgR rate is 13%, in a range of 5% to 33%. A collaborative study of 9 European Union countries has led to the collection of data on 317 patients who were first seen between 1983 and 1997 and achieved CCgRs with IFN-alpha alone or in combination with hydroxyurea. The median time to first CCgR was 19 months (95% CI, 17-21; range, 3-84 months). At last contact, 212 patients were still alive and in continuous CCgR; 105 patients had lost CCgR, but 53% of them were still alive and in chronic phase. IFN-alpha treatment was discontinued permanently in 23 cases for response loss, in 36 cases for chronic toxicity (15 are still in unmaintained continuous CCgR), and in 8 cases because it was believed that treatment was no longer necessary (7 of these 8 patients are still in unmaintained continuous CCgR). The 10-year survival rate from first CCgR is 72% (95% CI, 62%-82%) and is related to the risk profile. High-risk patients lost CCgR more frequently and more rapidly and none survived more than 10 years. Low-risk patients survived much longer (10-year survival probability 89% for Sokal low risk and 81% for Euro low risk). These data point out that a substantial long-term survival in CCgRs is restricted mainly to low-risk and possibly intermediate-risk patients and occurs significantly less often in high-risk patients.
Source: PubMed