ABSTRACT
AIM: To analyze the specific features of recurrences of acute promyelocytic leukemia (APL) in children after standard therapy with daunorubicin, cytosine arabinoside (Ara-C), all-trans retinoic acid (ATRA) and to develop further programmed treatment policy. SUBJECTS AND METHODS: The study included 9 patients with recurrent APL. The recurrences developed significantly more frequently in a very high-risk group (patients with minimal residual disease being preserved after the intensive therapy phase). Induction used arsenic trioxide (ATO) and/or standard chemotherapy + ATRA; ATO monotherapy was in consolidation. CD34+ cells were mobilized until molecular remission was achieved with high-dose Ara-C and granulocyte colony-stimulating factor. Pretransplantation conditioning involved melfalan as a basic drug in combination with high-dose AraC (5 pts), treosulfan (1 pt) or bisulfan (1 pt). Six patients received gemtusumab ozogamicin, 3-9 mg/m2, at different stages of therapy. RESULTS: Before therapy one patient died; 8 patients achieved the second molecular remission; CD34+ cell mobilization and sampling were effective in 7 cases. Five patients were in long-term molecular remission after autologous hemopoietic stem cell transplantation (autoHSCT). Follow-up was 23-40 months. One patient is being prepared for transplantation. Following autoHSCT, another patient with a developed repeat recurrence died from complications due to related partially compatible transplantation. Visceral, including cardiological, toxicity of therapy was insignificant. In the APL-2003 protocol, overall and event-free survival rates were 93 +/- 3 and 76 +/- 6%, respectively. CONCLUSION; The application of ATO and autoHSCT in recurrent APL makes it possible to achieve and preserve the second molecular remission in case of insignificant extrahematological toxicity. Russian clinics should have access to ATO.
Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Hematopoietic Stem Cell Transplantation , Leukemia, Promyelocytic, Acute/prevention & control , Transplantation Conditioning/methods , Adolescent , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Arsenic Trioxide , Arsenicals/administration & dosage , Arsenicals/therapeutic use , Child , Child, Preschool , Combined Modality Therapy , Disease-Free Survival , Humans , Infant , Leukemia, Promyelocytic, Acute/drug therapy , Leukemia, Promyelocytic, Acute/mortality , Leukemia, Promyelocytic, Acute/surgery , Oxides/administration & dosage , Oxides/therapeutic use , Remission Induction , Secondary Prevention , Transplantation, AutologousABSTRACT
AIM: To analyse the results of treatment of children and adolescents with acute promyelocytic leukemia (APL) including polychemotherapy and ATRA (protocols APL 93, 98 and 2003). MATERIAL AND METHODS: The course of the disease, modification of the treatment protocols with reduction of anthracyclines and ATRA doses, results of molecular monitoring of PML/RARalpha transcript have been analysed for 107 APL patients. RESULTS: For prognosis of the disease important are initial characteristics of the patient and the time of the tumor regress assessed by molecular methods--establishment of molecular remission and molecular recurrence. CONCLUSIONS: In APL it is necessary to conduct molecular monitoring especially in patients at high risk and with poor prognosis in a decrease of treatment intensity for toxicity relief. Detection of molecular recurrence is indication for treatment. To raise efficacy of APL recurrence therapy it is necessary to design a special updated protocol.
