Acute promyelocytic leukemia: evolving therapeutic strategies

Purpose To determine the results of treatment combining all-trans-retinoic acid (ATRA) and chemotherapy (CT) in childhood acute promyelocytic leukemia (APL). Patients and Methods Children (< 18 years) with newly diagnosed APL were included in the APL93 trial, treated by ATRA followed or combined with daunorubicin-cytarabine, and then randomly assigned between no maintenance, intermittent ATRA, continuous CT, or both. Results Of the 576 patients included in APL93 trial, 31 (5%) were children, including 22 girls (71%) and nine boys (29%). Thirty of the children (97%) obtained complete remission (CR). ATRA syndrome occurred in four children (13%), who all achieved CR, and headaches occurred in 12 children (39%), with signs of pseudotumor cerebri in five children (16%). Seven patients (23%) relapsed. None of the eight patients who received both ATRA and CT for maintenance relapsed. All relapsing patients achieved a second CR. Twenty-two patients remained in first CR after 43+ to 96+ months, six remained in se...

Outcome of Childhood Acute Promyelocytic Leukemia With All-Trans-Retinoic Acid and Chemotherapy

Between 1988 and 1995, 341 children with acute myeloid leukaemia (AML) were treated on the Medical Research Council Acute Myeloid Leukaemia Trial (MRC AML10). The 5-year overall survival was 57%, much improved on previous trials. However, there were 47 deaths (13.8%), 11 of which were associated with bone marrow transplantation (BMT). The treatment-related mortality was significant at 13.8%, but decreased in the latter half of the trial from 17.8% in 1998–91 to 9.6% in 1992–95 (P = 0.03%). The main causes of death were infection (65.9%), haemorrhage (19.1%) and cardiac failure (19.1%). Fungal infection was a significant problem, causing 23% of all infective deaths. Haemorrhage occurred early in treatment, in children with initial white cell counts >100 × 109/l (P = 0.001), and was more common in those with M4 and M5 morphology. Cardiac failure only occurred from the third course of chemotherapy onwards, with 78% (7/9) in conjunction with sepsis as a terminal event. Some deaths could be prevented by identifying those most at risk, and with prompt recognition and aggressive management of complications of treatment. Future options include the prophylactic use of antifungal agents, and the use of cardioprotectants or alternatives to conventional anthracyclines to decrease cardiac toxicity.

Treatment‐related deaths during induction and first remission of acute myeloid leukaemia in children treated on the Tenth Medical Research Council Acute Myeloid Leukaemia Trial (MRC AML10)

Acute myeloid leukemia (AML) has posed significant therapeutic challenges to pediatric oncologists. Despite intensive therapy, half of the children with AML relapse and die from their disease. Efforts to identify risk factors in AML are directed toward defining populations who may benefit from alternative therapies. Patients at lower risk for relapse may benefit from treatment de-escalation, sparing them adverse side effects. Management of high-risk patients may prove more difficult, as the nearly myeloablative nature of AML therapy leaves little room for therapy escalation short of stem cell transplantation. This review evaluates prognostic factors in pediatric AML and discusses the feasibility of using these factors in riskadapted therapy regimens. The Oncologist 2007;12: 341–355

Prognostic Factors and Risk-Based Therapy in Pediatric Acute Myeloid Leukemia

All-trans retinoic acid (ATRA) is a known inducer of differentiation in acute promyelocytic leukemia. To improve the outcome of children with acute promyelocytic leukemia, ATRA has been applied since 1994 as an additional induction element inthe AML-BFM 93 study. In a retrospective study, we compared 22 children treated with ATRA (median age: 9.3 years; range: 1.8-16.3) with 22 patients receiving conventional therapy (median age: 12.3 years; range: 3.2-16.7). Twenty-one of the children achieved complete remission. Only one patient died early from bleeding complications after 3 days administration of ATRA. In the control group, seven early deaths occurred (Fisher exact test; p<0.04). Two children died from intracerebral hemorrhages. Two patients suffered from sepsis during aplasia after induction therapy, and one child did not respond to treatment. The 5-year overall survival (OS) and event-free survival (EFS) of the children who received ATRA followed by chemotherapy were significantly bettercom-pared with conventionally treated children [OS: 0.87 +/- 0.9 vs 0.45 +/- 0.11, p (log rank) <0.003; EFS: 0.76 +/- 0.11 vs 0.43 +/- 0.11 p (log rank) <0.02]; the median observation time was 2.8 years (19-76 months). However, nearly all children suffered from common side effects such as headache, fever, joint, muscle and bone pain, weight gain, or dermatitis. In three patients, a retinoic acid syndrome was observed. Interruption of ATRA treatment and application of dexamethasone, necessary in 12 children, controlled theadverse effects. ATRA treatment could be resumed in 18 patients. In conclusion, ATRA treatment during induction could avoid early deaths in children with acute promyelocytic leukemia with considerable but manageable toxic side effects.

Treatment with all-trans retinoic acid in acute promyelocytic leukemia reduces early deaths in children

Acute promyelocytic leukemia (APL) is a distinct subtype of acute myeloblastic leukemia (AML). In this report, we present the clinical features, management, and outcome of pediatric patients with APL treated with all-trans-retinoic acid (ATRA). Of 52 newly diagnosed cases of APL between February 1992 and December 1996, 15 were in the pediatric age group (younger than 15 years). Four patients were treated with ATRA alone and 11 were allocated to receive ATRA followed by chemotherapy. Eighty-six percent of the patients achieved a complete response. The patients who received ATRA alone as maintenance therapy had relapses with a median duration of remission of 8 months (range 6-12). The patients who received ATRA, followed by consolidation chemotherapy, had a prolonged duration of remission, with a median of 20 months (range 13-28). In addition, rapid correction of coagulopathy was observed in these patients. The median duration for correction of coagulopathy was 7 days (range 5-11) and the median duration for recovery from neutropenia after chemotherapy was 10 days (range 7-20). Two major side effects of ATRA were hyperleukocytosis and retinoic acid syndrome. Significantly prolonged disease-free survival was seen in patients who received ATRA with chemotherapy. APL is not uncommon in the pediatric age group. ATRA was well-tolerated by these patients. Consolidation with chemotherapy helps in prolonging the disease-free survival in patients with APL in comparison to treatment with ATRA alone.

All-trans-retinoic acid (ATRA): pediatric acute promyelocytic leukemia.

The records of 458 patients with acute lymphoblastic leukemia (ALL) have been reviewed. The diagnosis of ALL was based on clinical examination and morphological, cytochemical and immunophenotypic characteristics (20% or more blasts reacting with lymphoid monoclonal antibodies) of blood and/or bone marrow. Blast cells of 6 (1.3%) patients showed positive reaction with Sudan black B (SBB) in the absence of reactivity to any other myeloid markers. Positive reaction with SBB stain cannot be considered specific for myeloid series.

K.S. Tapan

Papers

All-trans-retinoic acid (ATRA): pediatric acute promyelocytic leukemia.

Sudan Black B Positivity in Acute Lymphoblastic Leukemia