NPM1, FLT3 and CEBPA mutations in pediatric patients with AML from Argentina: incidence and prognostic value

Mutations in NPM1, FLT3 and CEBPA genes are found in 25-35 % of adult acute myeloblastic leukemia (AML) cases and correlate with prognosis. To date, there have been no reports about these mutations in pediatric AML from Argentina. The aims of the present study were to describe the incidence of NPM1, FLT3 and CEBPA mutations and to analyze their prognostic impact in this population. The incidences of these mutations within a population of 216 pediatric AML cases were: NPM1-mutated 4.2 %, CEBPA-mutated 1.9 %, FLT3-ITD 10.2 % and FLT3-TKD 7.9 %. Among 33 patients with normal karyotype, we found significantly higher frequencies for NPM1-mutated 24.2 % and CEBPA-mutated 12.1 %. Overall survival (pOS) for the 163 eligible non-acute promyelocytic leukemia cases was 46.2 ± 4.3 %, while leukemia-free survival probability was 51.0 ± 4.4 % (n = 135). The NPM1-mutated/FLT3-ITD-negative genotype showed better outcome than any other combined NPM1/FLT3 genotype; this difference was statistically significant within the group of high-risk patients (pOS ± SE 83.3 ± 15.2 % versus 33.1 ± 4.7 %; p = 0.0251). This is the first report of the frequencies of these mutations in Argentina. Despite the limited number of patients, a favorable prognosis of AML with genotype NPM1-mutated/FLT3-ITD-negative was confirmed. This is especially relevant within the high-risk group of patients, as it may contribute to the detection of patients with better prognosis, and thus avoid unnecessary treatment intensification.

Childhood acute lymphoblastic leukemia: prognostic value of initial peripheral blast count in good responders to prednisone

PURPOSE

To assess the value of initial peripheral blast count in patients with acute lymphoblastic leukemia (ALL) and prednisone good response (PGR).

PATIENTS AND METHODS

From January 1990 to December 1995, 403 consecutive patients with newly diagnosed ALL were enrolled in the authors' protocol 1-ALL90-BFM/HPG. Prednisone good response was defined as a blast count of less than 1,000/microL and a prednisone poor response (PPR) as a blast count of at least 1,000/microL, both in peripheral smears, after 7 days of oral prednisone (60 mg/m2 per day) and one intrathecal dose of methotrexate. In the PGR group, patients were divided into two subgroups: patients who had less than 1,000 blasts/microL at diagnosis and those with at least 1,000 blasts/microL at diagnosis.

RESULTS

Three-hundred thirty-seven patients (90%) had PGR and 37 had (10%) PPR. At 5-year follow-up, event-free survival estimates were 67 +/- 3.8% and 38 +/- 8% for PGR and PPR, respectively (P = 0.0001). In the PGR group, 114 patients (34%) had an initial blast count of less than 1,000/microL and 223 (66%) had an initial blast count of at least 1,000/microL. The authors compared the clinical and laboratory characteristics of these subgroups at diagnosis and outcome and detected significant differences in white cell count, incidence of T immunophenotype, and presence of mediastinal or spleen enlargement. However, there were no differences in response to induction treatment, death in complete remission, relapses, or event-free survival probability.

CONCLUSIONS

In the PGR group, regardless of the initial blast count, both subgroups had the same outcome. The PGR group with an initial blast count of at least 1,000/microL had significantly higher white cell counts. T markers, and mediastinal or spleen enlargement at diagnosis. Response to prednisone is a practical, inexpensive, and good prognostic factor in childhood ALL.

Acute lymphoblastic leukemia presenting as acute hepatic failure in childhood

We report a 7-year old white girl who was admitted because of acute severe hepatic failure. Her complete blood count revealed pancytopenia and a bone marrow aspiration was consistent with acute lymphoblastic leukemia (ALL). Blasts cells were positive for cytoplasmic CD3 and cell surface T-associated markers. Viral, metabolic, immune and toxic causes for hepatic failure were ruled out. Treatment pre-phase with prednisone was started and liver function tests clearly improved after one-week therapy. However, due to her hepatic insufficiency, daily etoposide was administered orally during 15 days. On day 33 complete remission was achieved and hepatic function was normal, except for an increase in the bilirubin level which normalized on day 72. She received our current treatment for intermediate risk ALL and is still receiving continuation phase therapy, currently, with normal liver function and good tolerance to chemotherapy + 8 months after achieving complete remission.

Good outcome of children with acute myeloid leukemia and t(8;21)(q22;q22), even when associated with granulocytic sarcoma: a report from a single institution in Argentina

BACKGROUND

The association between t(8;21) and granulocytic sarcoma (GS) is well known, but to the authors' knowledge the prognostic significance of GS in these patients has not been defined clearly.

METHODS

Between January 1990 and July 1999 174 children with acute myeloid leukemia were admitted to the study institution. Translocation (8;21) was identified in 20 patients (11.5%). Eighteen patients were evaluable for the current study and 8 presented with GS at the time of diagnosis (GS+).

RESULTS

The authors defined two groups of patients: those who were GS+ and those who were GS-. One patient in the GS+ group and two patients in the GS- group died during the induction phase of the study. Complete remission was achieved in seven patients in the GS+ group and eight patients in the GS- group. Two patients developed a recurrence in the GS+ group as did one patient in the GS- group. The event free-survival probability (the standard error) was 58% (18%) in the GS+ group and 70% (14%) in the GS- group. Localization of GS was in only one site in seven patients and at multiple sites in one patient. Patients with an epidural mass received local radiotherapy (one patient) or surgery (two patients). Two of these patients developed paraplegia as sequelae: one patient after surgery and one patient after radiotherapy. One patient with orbital GS received local radiotherapy because of progressive proptosis. The remaining four patients had a complete resolution of the GS with chemotherapy only.

CONCLUSIONS

In the current study of patients with t(8;21)(q22;q22), the presence of granulocytic sarcoma was not found to be an adverse prognostic factor. However, careful attention should be paid, especially to patients with an epidural site, to avoid sequelae. Chemotherapy appears to be the optimum treatment for these children.

Childhood acute promyelocytic leukemia: no benefit of all-trans-retinoic acid administered in a short-course schedule

From January 1990 to August 1997, 29 consecutive patients were treated with newly diagnosed primary acute promyelocytic leukemia (APL) at the authors' Institution. Of these, 27 (16 boys and 11 girls) were evaluable. Median age at diagnosis was 6.3 (range: 1.9-15.7) years. This population was treated with two consecutive protocols: 13 patients were included in the AML-HPG-90 protocol and 14 in the AML-HPG-95. The initial treatment was the same for both protocols: an induction 8-day phase with cytarabine, idarubicin, and etoposide was followed by a consolidation with cyclophosphamide, cytarabine, 6-mercaptopurine, vincristine, doxorubicin, and prednisone. Two courses of intensification with high-dose (HD) cytarabine and etoposide were given in the first study. Only one intensification course was administered in the second study, with HD cytarabine plus idarubicin or etoposide decided by randomization. Complete remission was achieved in 67% (18/27) of cases. Mortality on induction was quite high, 30% (8/27) mainly due to hemorrhages from disseminated intravascular coagulation (DIC). The event-free survival estimate for all patients was 0.47 (SE: 0.1). From April 1994, all-trans-retinoic acid (ATRA) was administered just during the first days of the induction phase (median: 9, range: 2-27) to stop or prevent DIC. Eighteen patients received ATRA and 9 did not. Three patients developed signs of ATRA syndrome during the first days of administration but no one died due to this toxicity. The impact of a short course of ATRA on early control of DIC was studied by analyzing the number of platelet, cryoprecipitate, and fresh frozen plasma transfusions during the induction phase in both groups. No statistical differences in complete remission rate, early mortality, need of transfusion of blood components for DIC, and survival estimates could be established between patients who received ATRA and those who did not. ATRA used in a short-course schedule during induction of APL did not stop early mortality due to DIC. Moreover, survival results did not improve with this method of ATRA usage. Longer periods of ATRA administration during APL therapy are strongly recommended.

Acute trilineage leukemia with monosomy of chromosome 7 following an acute promyelocytic leukemia

We describe an 8 year old boy who had received chemotherapy for an acute promyelocytic leukemia and developed a secondary leukemia 27 months after the diagnosis of this first malignancy. Blasts cells were positive for cytoplasmic markers CD22, CD3 and myeloperoxidase. Cell surface T and myeloid-associated markers were also detected. Cytogenetic study disclosed monosomy 7. The patient achieved complete remission, but relapsed 15 months later with identical immunophenotypic and cytogenetic findings. Three-lineage commitment is proved by the expression of specific criteria for myeloid, and lymphoid T and B typing. A multipotent immature progenitor must be the target of leukemogenic agents. The prognosis is obviously ominous.

Treatment results in childhood acute lymphoblastic leukemia with a modified ALL-BFM'90 protocol: lack of improvement in high-risk group

We report results achieved in our institution with an acute lymphoblastic leukaemia risk-oriented treatment trial opened in January 1990 and closed on December 1995. The study was similar to the German ALL-BFM'90, except for using Protocol III for the standard-risk group, 2 g/m2 of methotrexate in Protocol M, and preventive cranial irradiation for the high-risk group only. The high-risk group included mostly patients with prednisone poor initial response and/or adverse cytogenetic features. This analysis included 374 patients, whose mean age was 6 years (range: 1 month-17 years). The overall complete remission rate was 94.4% (353/374) and the 5-year event-free survival (standard error) probability is 64(5)%. The 5-year event-free survival estimates for each risk group were: (1) high-risk group 37(5)%; (2) intermediate-risk group 66(1)%; and (3) standard-risk group 74(4)% (P = 0.0001). There are significantly higher-rates of isolated bone marrow and testicular relapses in the high-risk subset of patients. Our dismal results and the published experience, lead us to conclude that the optimal treatment for these high-risk acute lymphoblastic leukaemia patients is not currently known.

[Translocation t(9;11) in acute childhood lymphoblastic leukemia]

We report a case of a de novo acute lymphoblastic leukaemia (ALL) with t(9;11) (p21;q23) and a novel translocation t(2;8) (p15;q24). The former is characteristic of acute nonlymphoblastic leukaemia (ANLL) and has rarely been detected in ALL. The blasts showed L2 morphology by the French American British (FAB) classification and pre B ALL immunophenotype.

Acute myelogenous leukemia in Down's syndrome: report of a single pediatric institution using a BFM treatment strategy

Between July 1990 and December 1995, 111 new consecutive pediatric patients with acute myelogenous leukemia (AML) have been treated in our institution. Eleven of them (9.9%) had Down's syndrome (DS), 6 boys and 5 girls. The median age was 22.5 (range 10-40) months. FAB subtypes were the following: M7: 6, M4: 3, and M0: 2. Five of them had previously had myelodysplasia and in 3, all FAB M7, myelofibrosis was detected. This population was treated with two consecutive protocols. Nine patients were included in the AML-HPG-90 protocol and 2 patients in the AML-HPG-95 study, respectively. However, all DS patients in this series received the same treatment. Eight patients achieved complete remission: two patients received two cycles of intensification with high dose (HD) ara-C, and 1 patient, only one cycle; the other 5 were prevented from receiving such therapy because of unacceptable toxicity or death. At 45 months, event-free survival and overall survival estimates were 0.30, S.E. 0.16. Mortality was remarkably high. All deaths (7) were associated with sepsis (5) or pulmonary infection (2). Three deaths occurred before achieving complete remission, 3 patients died during the consolidation phase and 1 died whilst off treatment. No one presented leukemic relapse. We conclude that this AML-BFM treatment strategy is highly toxic to children with DS and AML in our setting. Efforts will be made to improve clinical support and to administer less intensive therapy to this particular pediatric AML subgroup, which, in fact, has a better prognosis than the same non-trisomic population.

Acute myeloid leukemia as a second malignancy: report of 9 pediatric patients in a single institution in Argentina

BACKGROUND

Acute myeloid leukemia (AML) is well-recognized as one of the most important second malignancies. We report the occurrence of secondary AML (sAML) in our institution.

PROCEDURE

From September 1987 to August 1996 we have observed sAML in 9 patients (median age 4 years), 5 of them previously treated for hematologic malignancies (group I): acute lymphoblastic leukemia (n = 2), AML (n = 1), non-Hodgkin lymphoma (n = 1). Hodgkin disease (n = 1), and 4 of these 9 patients treated for solid tumors (group II): neuroblastoma (n = 1), retinoblastoma (n = 1), Wilms tumor (n = 1), and central nervous system germinoma (n = 1).

RESULTS

All the patients had topoisomerase II inhibitors as part of treatment of their first malignancy, but only 5 patients received epipodophyllotoxins. Alkylating agents were part of primary therapy in 8 of 9 patients. The latency period for the development sAML was 26.5 (range = 2-55) months. The morphologic FAB features of sAML were M5 (n = 5), M4 (n = 3), and M2 (n = 1). Cytogenetic studies showed r11q23 in 3 patients, all of them with prior hematological malignancies. Initial therapy for sAML in all cases was chemotherapy (including cytarabine in combination with idarubicin and etoposide or doxorubicin or mitoxantrone). Three patients died during induction and 6 achieved complete hematologic response. Three of these patients remain disease free at +15, +51, and +99 months post-remission (including one post allogeneic BMT). The remaining 3 patients died, 1 in complete remission one month after diagnosis and 2 relapsed and died with progressive disease (one post allogeneic BMT).

CONCLUSIONS

Secondary AML is a sequela of oncologic treatments with specific cytogenetic abnormalities and poor outcome. A few patients can achieve long-term survival even with standard chemotherapy.

Hodgkin disease in children: results of a prospective randomized trial in a single institution in Argentina

PURPOSE

To compare prospective treatment strategies in childhood Hodgkin disease to the following subsets of patients: a) Favorable prognostic group: these patients were randomized to receive 6 vs. 3 CVPP chemotherapy cycles without radiotherapy (CVPP: cyclophosphamide, vinblastine, procarbazine, and prednisone. The scheme was repeated every 28 days). b) Intermediate prognostic group: these patients were randomized to receive 6 cycles of CVPP or AOPE (AOPE: Adriamycin, vincristine, prednisone, and etoposide). Between the third and fourth cycles, all patients in this group received radiotherapy (RT)(30-40 Gy to initially involved areas). c) Unfavorable prognostic group: those patients received a single arm regimen of 6 cycles of CCOPP/CAPTe (3 of each combination) every 28 days. All these patients received radiotherapy (30-40 Gy to initially involved areas).

RESULTS

From October 1987 to December 1994, a total of 114 children and adolescents were evaluated. Mean age was 9 (range 2-17) years. There were 72 boys and 42 girls. With a median follow-up of 5 (range 1.5-8.7) years, at 80 months event-free survival (EFS) and overall survival (OS) for the whole cohort are 0.809 (SE: 0.04) and 0.873 (SE: 0.04), respectively (SE: Standard Error). Favorable prognostic group (n = 26) EFS is 0.831 (0.09) (Arm CVPP x 3:0.857 (0.13) and Arm CVPP x 6: 0.875 (0.08); p = non significant). Intermediate prognostic group (n = 64) EFS is 0.806 (0.05) (Arm CVPP x 6 + RT: 0.872 (0.05) and Arm AOPE x 6 + RT: 0.667 (0.10); p = 0.04). Unfavorable group (n = 24) EFS is 0.829 (0.07).

CONCLUSIONS

Results of treatment for the whole group are satisfactory. However, 3 cycles of CVPP without radiotherapy obtain equal EFS than 6 cycles without radiotherapy in the favorable prognostic group. In the intermediate prognostic group, 6 cycles of CVPP plus radiotherapy obtain a superior EFS than 6 cycles of AOPE plus radiotherapy. With the success of treatment for Hodgkin disease in children, future research needs to be focused in reducing toxicity without altering the excellent actual outcome.

Results of a BFM-based protocol for the treatment of childhood B-non-Hodgkin's lymphoma and B-acute lymphoblastic leukemia in Argentina

PURPOSE

To report the feasibility and results of a study based on the BFM-ALL. NHL/86 protocol for B-non-Hodgin's Lymphoma (NHL) and B-Acute Lymphoblastic Leukemia (B-ALL) in Argentina. Design. Prospective, single arm, non-randomized trial.

PATIENTS AND METHODS

From August 1988 to December 1993, 87 consecutive patients with B-NHL/B-ALL were admitted and 82 were eligible. The therapy was stratified according to stage. All patients received a cytoreductive prephase with cyclophosphamide and prednisone. Those with stage I-II were treated with three 5-day blocks of combined intense chemotherapy including dexamethasone, cyclophosphamidie, ifosfamide, cytarabine, teniposide, doxorabicin, and 500 mg/m2 of methotrexate as a 24 hour continuous infusion. Stage III received 6 blocks and those with stage IV/B-ALL received 6 intensified blocks in which 2 g/m2 of 24 hour continuous infusion methotrexate and vincristine were added. Triple intrathecal therapy was given for CNS prevention. After the first two blocks the response was assessed and those with a partial response were offered optionallya second look surgery or local radiotherapy.

RESULTS

With a median follow-up of 38 (range 16-71) months, the event-free survival (pEFS) for the whole group was 0.69 (Stage I-II n = 16 pEFS = 0.94, stage III n = 50 pEFS = 0.66, Stage IV n = 7 pEFS = 0.43, B-ALL n = 9 pEFS = 0.66). Patients with stage III abdominal tumors who achieved a partial response by imaging studies after induction had a significantly higher risk of relapse than those with a complete response (p = 0.02). Relapse was the most frequent event Toxicity was mainly hematological.

CONCLUSIONS

The application of this protocol was feasible in our setting and its results comparable to the German study. Patients with stage I-II had an excellent outcome. Those with stage III and B-ALL achieved an encouraging event-free survival, however those with abdominal tumors and partial response to induction chemotherapy fared less favourably. This strategy was less effective for patients with initial CNS disease.

Results of treatment with an intensive induction regimen using idarubicin in combination with cytarabine and etoposide in children with acute myeloblastic leukemia

We report results achieved in our institution with a study opened in July 1990 (similar to the German AML-BFM-87 in which daunorubicin was replaced by idarubicin in the induction phase and cranial preventive radiotherapy was omitted) and closed in December 1994, for the treatment of newly diagnosed acute myeloblastic leukemia (AML), without prior malignancies except for myelodysplasia. This evaluation included 68 patients, whose mean age was 6 years (range: 1 month-16 years). Thirty-nine were boys and 29 were girls. Complete remission rate was 80.9% (55/68), death on induction rate was 14.7% and induction failure rate was 4.4%. At median follow up of 38 months (range: 12-66 months), the 4-year event-free survival (EFS) estimate was 0.428 (S.E.: 0.062), event-free interval (EFI) estimate was 0.529 (S.E.: 0.07) and overall survival (OS) estimate was 0.44 (S.E.: 0.071). We conclude that idarubicin in combination with cytarabine and etoposide is a highly effective regimen for induction in children with AML. Although preventive cranial irradiation was not delivered, we have observed only one combined CNS relapse. Finally, we corroborate that in this setting two definite risk groups may be identified in children with AML.

Tandem triplication and quadruplication of chromosome 21 in childhood acute lymphoblastic leukemia

A 5-year-old girl with ALL was shown to have a leukemic clone characterized by a triplication and quadruplication of chromosome 21, arranged in tandem, at diagnosis and relapse, respectively. To our knowledge, this is the second report of this chromosomal anomaly in ALL, which was confirmed by in situ staining. The karyotype evolution in the leukemic clone from triplication to quadruplication at relapse emphasizes the association of chromosome 21 with hematopoietic malignancies.