Submitted March 21, 2006
Accepted July 6, 2006
Imatinib mesylate discontinuation in patients with chronic myelogenous leukemia in complete molecular remission for more than two years
Philippe Rousselot, Francoise Huguet, Delphine Rea, Laurence Legros, Jean Michel Cayuela, Odile Maarek, Odile Blanchet, Gerald Marit, Eliane Gluckman, Josy Reiffers, Martine Gardembas, and Francois-Xavier Mahon*
Federation d'hematologie et Centre d'Investigation Clinique, Hopital Saint-Louis, Paris, France
Service d'Hematologie, Hopital de Purpan, Toulouse, France
Service d'hematologie, Hopital Larchet, Nice, France
Laboratoire Central d'Hematologie, INSERM U728, Hopital Saint-Louis, Paris, France
Laboratoire d'hematologie, CHU d'Angers, Angers, France
Service des Maladies du Sang, CHU du Haut Leveque, Pessac
Institut Bergonie, Bordeaux, France
Service d'Hematologie, CHU d'Angers, Angers
Laboratoire Hematopoiese normale et pathologique, Universite Victor Segalen,Bordeaux 2, INSERM E217
* Corresponding author; email: francois-xavier.mahon{at}umr5540.u-bordeaux2.fr.
In the present study, we address the issue of the discontinuation of imatinib in chronic myelogenous leukaemia with undetectable residual disease for more than 2 years. Twelve patients were included. The median duration of RTQ-PCR negativity and imatinib therapy were respectively 32 months (24-46) and 45 months (32-56) before imatinib interruption. Six patients displayed a molecular relapse with a detectable BCR-ABL transcript at respectively 1, 1, 2, 3, 4 and 5 months. Imatinib was then re-introduced and led to a novel molecular response in most patients. Six other patients (50%) have still an undetectable level of BCR-ABL transcript after a median follow up of 18 months (9-24). We hypothesize that relapses observed within 6 months reflects the kinetic of undetectable dividing CML cells. Those cells may be eradicated or controlled in long term non relapsing patients described in our study.
