Treatment and long-term results in children with acute myeloid leukaemia treated according to the AIEOP AML protocols.

Since 1982, four consecutive studies on childhood acute myeloid leukaemia (AML) (namely LAM-82, -87, -87M and -92) have been conducted in Italy by the Associazione Italiana di Ematologia e Oncologia Pediatrica (AIEOP) group. The induction therapy of the first three studies consisted of daunorubicin and cytarabine structured in a 3+7 backbone. In the most recent protocol (LAM92), patients received two induction courses including idarubicin, cytarabine and etoposide. Patients with acute promyelocytic leukaemia (20% of diagnoses) were included in LAM-87 and 87M studies. Postremissional therapy significantly changed over time, with an ever-increasing role given to stem cell transplantation (SCT). The long-term outcome of patients enrolled in the LAM-82, 87 and 87M studies was comparable, whereas that of children treated according to LAM-92 study was significantly better (P<0.005). Either allogeneic or autologous SCT was employed as consolidation therapy in more than 75% of cases enrolled in this latter study. Patients enrolled in the LAM-92 study were stratified in standard and high-risk groups with different outcome (67 vs 47%, respectively, P=0.04). Altogether, the results obtained in these four studies have permitted a progressive refinement of treatment, contributing to the structure of the ongoing LAM-2002 protocol that stratifies patients according to the presence of definite genetic anomalies and response to induction therapy.

ALL-1 gene rearrangements in acute myeloid leukemia: association with M4-M5 French-American-British classification subtypes and young age.

We have analyzed by Southern blotting the ALL-1 (MLL, HRX, Hrtx 1) gene configuration in a series of 126 patients with acute myeloid leukemia (AML) representative of all ages and French-American-British Classification groups and correlated this genetic feature with clinical and biological features at diagnosis. ALL-1 gene rearrangements were detected in 17 of the 74 cases with M4-M5 (myelomonocytic and monocytic) AML and in 2 of the 52 cases with other leukemic subtypes (P < 0.01). Within the series of 74 M4-M5 patients, ALL-1 rearrangements were significantly associated with French-American-British Classification M5 (P = 0.009), high WBC (P = 0.002), and young age. In particular, all 5 infant (< 1.5 years) AML cases, 6 of the 19 (31%) patients between 1.5 and 18 years of age, and 6 of the 50 (12%) patients > 18 years old showed an altered ALL-1 genomic configuration (P < 0.001). Immunophenotypic characterization revealed coexpression of lymphoid and myeloid markers in 6 of 17 ALL-1 rearranged M4-M5 cases. The IgH gene configuration was studied in 77 of 126 AMLs. Five patients (6%) showed IgH clonal rearrangements and all were in the ALL-1 rearranged group (P < 0.0001). Our findings indicate that ALL-1 rearrangement is the commonest genetic alteration presently detectable in M4-M5 AML, particularly in childhood where it is found in up to one-third of all cases. The association of IgH rearrangements with ALL-1 alterations in AML, coupled to the frequent detection in this subset of lymphoid associated markers, further supports the origin of these tumors from a common multipotent precursor with bipotential lymphoid and monocytic differentiation capability.

Southern blot analysis of ALL-1 rearrangements at chromosome 11q23 in acute leukemia.

The chromosome 11q23 band is a genetic region frequently involved in nonrandom karyotypic abnormalities of acute leukemia. A genomic locus named ALL-1 or MLL, where 11q23 breakpoints are clustered, has been recently cloned and characterized. We have made use of an ALL-1-specific probe in Southern blot experiments to analyze the configuration of this gene in a large series of acute leukemia patients, representative of all different myeloid and lymphoid subtypes. Nine of 145 cases (6.2%) showed abnormal ALL-1 restriction fragments in leukemic DNAs. Of these nine cases, five patients in whom karyotypic data were available displayed chromosome 11q23 aberrations, including t(4;11) (three cases) and t(9;11) (two cases). Immunophenotypic and morphocytochemical characterization of ALL-1-rearranged acute leukemia revealed prevalence of poorly differentiated B lymphoid and/or monoblastic features. Considering the whole series, ALL-1 rearrangements were significantly associated with female sex, higher white blood cell counts at presentation, and very poor clinical outcome. The presence of residual disease was molecularly documented in one case at the time of clinical remission after induction treatment and was followed by early relapse. We conclude that ALL-1 rearrangements are new molecular markers of human leukemia with considerable diagnostic and prognostic relevance.

Prospective comparative study of bone marrow transplantation and postremission chemotherapy for childhood acute myelogenous leukemia. The Associazione Italiana Ematologia ed Oncologia Pediatrica Cooperative Group.

PURPOSE: This study was conducted to assess the comparative values of allogeneic bone marrow transplantation (BMT) and autologous bone marrow transplantation (ABMT) with sequential postremission chemotherapy (SPC) in children with acute myelogenous leukemia (AML) in first remission. PATIENTS AND METHODS: From March 1987 to March 1990, 161 assessable patients younger than 15 years of age with newly diagnosed AML were treated uniformly with two courses of daunorubicin and standard-dose cytarabine. After initial consolidation with a course of daunorubicin, cytarabine, and thioguanine (DAT), patients in complete remission (CR) were randomized to receive either ABMT or SPC, except for those with an HLA-matched sibling who were assigned to undergo BMT. SPC consisted of three additional courses of DAT, followed by three pairs of drugs administered sequentially for a total of six cycles. RESULTS: Overall, 127 of 161 patients attained CR (79%). The estimated probabilities of survival and event-free survival (EFS) at 5 years for all patients were 42% and 25%, respectively (median follow-up, 28 months). For the 127 complete responders, the 5-year probability of disease-free survival (DFS) was 31%, with a cumulative risk of relapse of 64%. For the purpose of this study, all complete responders were evaluated for analysis of disease outcome according to the intent-to-treat principle, regardless of whether they actually received the intended therapy. The 5-year DFS was 51% for the BMT group (n = 24), significantly higher (P = .03) than that observed for the other cohorts: 21% for ABMT (n = 35), 27% for SPC (n = 37), and 34% for a group of 31 nonrandomized (NR) patients. Bone marrow relapse was the most frequent cause of postremission failure in all therapeutic subgroups, including the BMT cohort, in which no deaths attributable to the toxicity of the procedure were recorded. CONCLUSION: The results of this study show that BMT is more effective than ABMT or SPC in preventing leukemia relapse and extending DFS duration in children with AML in first remission.

Mitoxantrone, etoposide, and intermediate-dose cytarabine: an effective and tolerable regimen for the treatment of refractory acute myeloid leukemia.

Thirty-two patients with refractory acute myeloid leukemia (AML) received salvage therapy with a single course of mitoxantrone 6 mg/m2 intravenous (IV) bolus, etoposide 80 mg/m2 IV for a period of 1 hour, and cytarabine (Ara-C) 1 g/m2 IV for a period of 6 hours daily for 6 days (MEC). Eighteen patients were primarily resistant to conventional daunorubicin and Ara-C induction treatment; eight patients had relapsed within 6 months from initial remission; six patients had relapsed after a bone marrow transplantation (BMT) procedure. Overall, 21 patients (66%) achieved a complete remission (CR), two (6%) died of infection during induction, and nine (28%) had resistant disease. Age greater than 50 years was the only factor predictive for a significantly lower response rate (P = .03). The median remission duration was 16 weeks; the overall median survival was 36 weeks. Severe myelosuppression was observed in all patients resulting in fever or documented infections in 91% of patients. Nonhematologic toxicity was minimal. We conclude that the MEC regimen has significant antileukemic activity and acceptable toxicity in salvage AML. Its benefit in front-line AML therapy is being investigated.

Extended intrathecal methotrexate may replace cranial irradiation for prevention of CNS relapse in children with intermediate-risk acute lymphoblastic leukemia treated with Berlin-Frankfurt-Münster-based intensive chemotherapy. The Associazione Italiana di Ematologia ed Oncologia Pediatrica.

PURPOSE: To assess the effect of treatment intensification and that of extended intrathecal methotrexate substitution for cranial irradiation in intermediate-risk acute lymphoblastic leukemia (ALL) children treated with a Berlin-Frankfurt-Münster (BFM)-based intensive chemotherapy. PATIENTS: Three hundred ninety-six children with non-B-ALL were enrolled onto the Associazione Italiana di Ematologia ed Oncologic Pediatrica (AIEOP) ALL 88 study. Standard risk (SR) included patients with low tumor burden (BFM risk index [RI], < 0.8); intermediate risk (IR) were patients with an RI > or = 0.8 but less than 1.2; and high risk (HR) were those with an RI > or = 1.2 or CNS involvement at diagnosis. The treatment schedule was a modified version of the ALL-BFM 86 study. CNS-directed treatment consisted of high-dose methotrexate (HD-MTX; 5 g/m2 for four courses) plus intrathecal methotrexate (IT-MTX; nine doses); IR patients additionally received extended IT-MTX (nine doses during continuation therapy); cranial irradiation was given only to HR patients. RESULTS: Of the 375 (94.7%) children who achieved remission, 1.3% had an adverse event other than relapse. The estimated event-free survival (EFS) at 6 years was 66.6% (SE 2.4) overall; 80.7% (4.5) in the SR patients, 77.5% (3.9) in the IR patients, and 54.5% (3.7) in the HR patients. Relapse occurred in 107 children (27.0%). Isolated CNS relapse occurred in 20 children (5.0%): 5 (6.3%) in the SR group, 1 (0.8%) in the IR group, and 14 (7.1%) in the HR group. The estimated 6-year CNS leukemia-free survival was 94.6% (1.2) overall: 93.5% (2.8) in the SR group, 99.1% (0.9) in the IR group, and 92.3% (2.0) in the HR group. CONCLUSION: Cranial irradiation may be omitted safely in IR ALL patients treated with BFM-based intensive chemotherapy when extended intrathecal chemotherapy is given. Because the CNS disease control was less complete in the SR group, these data challenge the effectiveness of HD-MTX for protection from CNS disease and support the protective role of extended intrathecal chemotherapy.

Differences in the proportions of fluoroquinolone-resistant Gram-negative bacteria isolated from bacteraemic children with cancer in two Italian centres.

The proportion of ciprofloxacin-resistant Gram-negative bacteria isolated from the blood of children with cancer (not receiving prophylaxis) was 10% in a paediatric hospital (Genoa) where the use of quinolones was highly restricted, compared with 41% in a department of haematology (Rome) where leukaemic adults, who received fluoroquinolone prophylaxis, were also treated (p < 0.0001). Moreover, simultaneous resistance to ciprofloxacin and ceftazidime, amikacin or imipenem-cilastatin was 11% in Genoa compared with 37% in Rome (p < 0.001). Ciprofloxacin resistance was more frequent in children who shared an environment with adults who were receiving ciprofloxacin prophylaxis.

A phase II study of VP-16, intermediate-dose Ara-C and carboplatin (VAC) in advanced acute myelogenous leukemia and blastic chronic myelogenous leukemia.

Thirty-one patients with either advanced AML (18) or blastic CML (13) were treated with an intensive timed sequential combination of VP-16 (100 mg/m2/day i.v., days 1-3 and 8-10), intermediate-dose Ara-C (500 mg/m2 i.v. over 1 h q 12 h, days 1-3 and 8-10) and carboplatin (150 mg/m2/day i.v. continuous infusion, days 1-3 and 8-10). CR rates were 9/18 (50%) for patients with AML and 9/13 (69%) for those with blastic CML, for an overall CR rate of 58%. Among patients with AML, CR rates for specific subgroups were: primary resistant disease 2/6; resistant relapse 1/5; second relapse 6/7. Ten patients were refractory to VAC and three (10%) died of complications during marrow hypoplasia. Median overall survival was 7 months, and median DFS of the 18 responders 4 months. The major toxicity was myelosuppression and infection. The VAC regimen has significant activity and acceptable toxicity in myelogenous leukemias. The very high response rate observed in blastic CML warrants further testing of carboplatin-based regimens in this poor-risk form of leukemia.

Mitoxantrone, etoposide and intermediate-dose Ara-C (MEC): an effective regimen for poor risk acute myeloid leukemia.

A total of 74 patients with poor risk AML (median age 36.7 years, range 4.5-60.6) received a single course of a regimen including mitoxantrone (6 mg/m2 intravenous bolus daily, days 1 to 6), etoposide (80 mg/m2 intravenous over 1 h, daily, days 1 to 6) and intermediate-dose Ara-C (1 g/m2 over 6 h, daily days 1 to 6). 28 patients had failed initial remission induction with daunorubicin and conventional doses of Ara-C, 16 patients had secondary AML and 30 patients had relapsed from initial remission (five within six months, 15 over six months and ten after autologous or allogeneic bone marrow transplantation). Overall 41/74 patients (55%) achieved complete remission, 26 (35%) had resistant disease and seven (10%) died of infection during marrow hypoplasia. A 4-day course of the same regimen was given as consolidation to patients in complete remission. Subsequent antileukemic therapy was individualized. Profound myelosuppression and pancytopenia were universal resulting in fever or documented infections in almost 100% of patient; major hemorrhagic complications occurred in 39% of patients. Extrahematologic toxicity was mild to moderate consisting mostly of nausea and vomiting, oral mucositis and transient liver and cardiac dysfunction. We conclude that the MEC combination chemotherapy program seems to be an effective antileukemic regimen for secondary and advanced AML, with acceptable toxicity.

Acute promyelocytic leukemia in children: experience of the Italian Pediatric Hematology and Oncology Group (AIEOP).

Scanty information is available on acute promyelocytic leukemia (APL) in children, and whether differences are present with respect to the adult form. The experience of the Italian Pediatric Hematology and Oncology Group (AIEOP) will be presented with respect to the following aspects: 1. Incidence of APL. The incidence of APL is generally considered to account for 3-9% of acute myelogenous leukemia (AML) in children and approximately 10-15% in adults. Recently a single Italian pediatric institution reported that APL constituted one third of observed acute nonlymphocytic leukemia (AnLL) cases. Data from the AIEOP cooperative study group have confirmed that APL in Italy is more frequently observed in children as compared to other countries. Environmental and/or genetic factors should be considered to explain such differences. 2. Diagnosis of M3v. The clinical and biological features of the largest series of childhood M3v will be presented and the problems encountered in the proper separation of 'classic' M3 and M3v in children will be discussed. 3. Clinical Aspects. The clinical features of the APL patients enrolled in the AIEOP study groups since 1989, will be presented with emphasis on the recent experience with the use of all-trans retinoic acid. 4. Analysis of PML/RAR alpha Fusion Transcripts. An RT-PCR analysis of 32 pediatric APL cases from cryopreserved bone marrow samples has been performed. It is concluded that APL in children did not differ significantly from the adult form, with the exception of a higher incidence of PML bcr3 breakpoint.

Acute promyelocytic leukemia in children: experience of the Italian Pediatric Hematology and Oncology Group (AIEOP).

Scanty information is available on acute promyelocytic leukemia (APL) in children, and whether differences are present with respect to the adult form. The experience of the Italian Pediatric Hematology and Oncology Group (AIEOP) will be presented with respect to the following aspects: 1. Incidence of APL. The incidence of APL is generally considered to account for 3-9% of acute myelogenous leukemia (AML) in children and approximately 10-15% in adults. Recently a single Italian pediatric institution reported that APL constituted one third of observed acute nonlymphocytic leukemia (AnLL) cases. Data from the AIEOP cooperative study group have confirmed that APL in Italy is more frequently observed in children as compared to other countries. Environmental and/or genetic factors should be considered to explain such differences. 2. Diagnosis of M3v. The clinical and biological features of the largest series of childhood M3v will be presented and the problems encountered in the proper separation of 'classic' M3 and M3v in children will be discussed. 3. Clinical Aspects. The clinical features of the APL patients enrolled in the AIEOP study groups since 1989, will be presented with emphasis on the recent experience with the use of all-trans retinoic acid. 4. Analysis of PML/RAR alpha Fusion Transcripts. An RT-PCR analysis of 32 pediatric APL cases from cryopreserved bone marrow samples has been performed. It is concluded that APL in children did not differ significantly from the adult form, with the exception of a higher incidence of PML bcr3 breakpoint.

Therapeutic strategies for postremission treatment in childhood acute myeloid leukemia (AML). The AIEOP experience 1987-1991.

From 1987 to 1990, intensive postremission chemotherapy was compared to autologous bone marrow transplant in previously untreated children with AML who received identical induction therapy with two courses of Daunorubicin (DNR) and conventional dose ARA-C (protocol AIEOP LAM 87). Overall, 121 of the 155 eligible patients achieved complete remission (CR) (78%). Patients in CR who lacked HLA-MLC compatible donor were randomized to receive either autologous BMT (Auto-BMT) or further sequential postremission therapy. Patients with HLA-MLC compatible donor were assigned to allogeneic BMT (Allo-BMT). Projected 3-years disease free survival (DFS) are 58% for Allo-BMT group, 24% for Auto-BMT group, 26% for chemotherapy group and 30% for a group of not randomized patients (intention to treat analysis). On March 1990 a pilot study LAM 87M was initiated. Patients in CR after induction therapy (identical to the previous protocol) receive a single intensification course consisting of high dose ARA-C plus DNR. The study continues to accrue patients.

Therapy-related acute myelomonocytic leukemia following successful treatment for acute promyelocytic leukemia.

We report a case of therapy-related acute myeloid leukemia (t-AML), M4 FAB subtype, with t(10;11)(p14;q21) chromosome abnormality developed in a patient treated for acute promyelocytic leukemia (APL) after 4 years of continuous complete remission (CCR). Two distinct forms of t-AML have been described: the classical type and the second type. Our case has many characteristics in common with the second type of t-AML such as: exposure to topoisomerase II active agents (idarubicin (IDA), mitoxantrone (MITOX), etoposide (VP16)), M4 FAB subtype, a latency period of 39 months and absence of a preleukemic phase. However, it differs in the chromosome 11 breakpoint (band q21 instead of q23) and absence of ALL-1 (Hrx, MLL, Htrx) gene involvement. This can represent the second observation of t-AML occurring after treatment for APL.

Immunophenotype of adult and childhood acute lymphoblastic leukemia: changes at first relapse and clinico-prognostic implications.

The immunologic features of leukemic cells at the time of 1st hematologic relapse were compared to those obtained at initial diagnosis in 128 patients (69 children and 59 adults) with acute lymphoblastic leukemia (ALL) treated at a single institution. An immunophenotypic change was observed in 59 cases (46%), more frequently in T (20/25) than in B (39/103) lineage ALL (80 vs 38%, P=0.0008), but with a similar incidence in adults and children. Of these cases, 34 (24 B- and 10 T-ALL) changed at relapse their intralineage subgroup affiliation, although no complete shift from B to T lineage ALL, or vice versa, was observed. The myeloid antigens CD13 and/or CD33 were frequently lost (2/5 cases) or acquired (12/123 cases) at relapse. In 21 cases, the immunophenotype at relapse was more undifferentiated than at diagnosis, while it was more differentiated in 13 cases. Initial treatment intensity or preceding treatment with teniposide did not affect the phenotypic profile at relapse. Complete response (CR) rate to salvage therapy and event-free survival were not influenced by the immunophenotypic shifts, nor by the presence, at relapse, of leukemic cells expressing the myeloid antigens CD13 and/or CD33. Univariate analysis suggested that prognosis after relapse was dependent on the duration of 1st CR, patients' age and immunophenotype at the time of diagnosis, with a worse outcome for patients with T lineage ALL and for patients with the less differentiated subgroup of B lineage ALL (CD19+ and CD10-). Multivariate analysis showed that only two factors, duration of 1st CR and grade of immunologic differentiation at diagnosis, have independent prognostic value in relapsed ALL.

Idarubicin intensified BUCY2 regimen in allogeneic unmanipulated transplant for high-risk hematological malignancies.

Twenty-nine consecutive patients with high-risk hematological malignancy aged from 3 to 58 years underwent an unmanipulated graft from an HLA-identical sibling after an irradiation-free preparative regimen consisting of idarubicin (IDA), 21 mg/m2/day administered by continuous infusion on days -12 and -11, followed by busulphan (BU), 4 mg/kg/day orally from day -7 to -4, and cyclophosphamide (CY), 60 mg/kg/day intravenously on days -3 and -2 (IDA-BUCY2). Most clinically relevant extra-hematological regimen-related toxicities consisted of stomatitis observed in all subjects and hemorrhagic cystitis occurred in five cases (17%) within 100 days after transplant. Six patients (21%) developed a grade 2 acute graft-versus-host disease (GVHD) and three (10%) a grade 3 or 4; extensive chronic GVHD was assessed in nine of 22 (41%) evaluable patients. So far, 12 patients have died and 17 are alive, 16 of whom disease-free, 5-41 months after transplant (median, 15 months). The causes of death were related to GVHD in three patients, to sepsis in one and to disease recurrence in the remaining eight. At present, only one of nine relapsed patients is alive. For all patients the actuarial probability of survival (OS) at 1 and 2 years +/- standard error (s.e.) was 63 +/- 9% and 52 +/- 10%, respectively. The actuarial probabilities of disease-free survival (DFS), relapse and transplant-related mortality (TRM) at both 1 and 2 years +/- s.e. were 53 +/- 9%, 35 +/- 9% and 16 +/- 7%, respectively. These results are encouraging but not substantially different from those obtained in 28 patients with malignancy in advanced phase transplanted after the standard BUCY2 regimen, who had an actuarial probability of OS, DFS, relapse and TRM projected at 10 years +/- s.e. of 54 +/- 10%, 57 +/- 9%, 36 +/- 9% and 11 +/- 6%, respectively. Although the retrospective comparison between the two groups does not seem to show any advantage in the use of the IDA intensified regimen, only a prospective randomized trial could answer this question.

Ear involvement in acute promyelocytic leukemia at relapse: a disease-associated 'sanctuary'?

Extramedullary (EM) involvement occurs infrequently in acute promyelocytic leukemia (APL) and usually involves skin and CNS. We describe seven patients (four observed at a single institution) who relapsed in various sites of the auditory apparatus, including the external canal and middle ear (temporal bone). Front-line treatment included ATRA and chemotherapy (six patients) or chemotherapy alone (one patient). Three patients had concomitant hematologic relapse, two had molecular relapse and two were in hematologic and molecular remission when ear localization was documented. Local symptoms that stimulated further diagnostic studies included ear bleeding/discharge in the first patient, but were mild in the others (hypoacusia, five patients; earache, two patients). Ear involvement by leukemia was documented by histological and/or molecular studies after local surgery in five cases, and by CT scan or NMR in the remaining patients. We suggest that the ear might represent a specific sanctuary for disease involvement in APL.

Myelodysplastic syndrome, juvenile myelomonocytic leukemia, and acute myeloid leukemia associated with complete or partial monosomy 7. European Working Group on MDS in Childhood (EWOG-MDS).

We reviewed the clinical features, treatment, and outcome of 100 children with myelodysplastic syndrome (MDS), juvenile myelomonocytic leukemia (JMML), and acute myeloid leukemia (AML) associated with complete monosomy 7 (-7) or deletion of the long arm of chromosome 7 (7q-). Patients with therapy-induced disease were excluded. The morphologic diagnoses according to modified FAB criteria were: MDS in 72 (refractory anemia (RA) in 11, RA with excess of blasts (RAEB) in eight, RAEB in transformation (RAEB-T) in 10, JMML in 43), and AML in 28. The median age at presentation was 2.8 years (range 2 months to 15 years), being lowest in JMML (1.1 year). Loss of chromosome 7 as the sole cytogenetic abnormality was observed in 75% of those with MDS compared with 32% of those with AML. Predisposing conditions (including familial MDS/AML) were found in 20%. Three-year survival was 82% in RA, 63% in RAEB, 45% in JMML, 34% in AML, and 8% in RAEB-T. Children with -7 alone had a superior survival than those with other cytogenetic abnormalities: this was solely due to a better survival in MDS (3-year survival 56 vs 24%). The reverse was found in AML (3-year survival 13% in -7 alone vs 44% in other cytogenetic groups). Stable disease for several years was documented in more than half the patients with RA or RAEB. Patients with RA, RAEB or JMML treated with bone marrow transplantation (BMT) without prior chemotherapy had a 3-year survival of 73%. The morphologic diagnosis was the strongest prognostic factor. Only patients with a diagnosis of JMML fitted what has previously been referred to as the monosomy 7 syndrome. Our data give no support to the concept of monosomy 7 as a distinct syndrome.

Prognostic value of rhodamine-efflux and MDR-1/P-170 expression in childhood acute leukemia.

The evidence that mechanisms other than P-170 expression may influence its "pump" and the retention/efflux of chemotherapeutic agents, prompted us to investigate the value of a functional multidrug resistance (MDR) assay in a series of childhood acute leukemia samples. Forty acute leukemia cases, mainly of lymphoid origin (ALL), were evaluated for MDR expression using a functional test based on rhodamine-123 efflux (Rhd-E). This was correlated with the quantification of P-170 external epitopes based on the positivity with the 4E3.16 and MRK16 monoclonal antibodies (MAbs). When compared with the status of the disease and response to treatment, the mean (m) Rhd-E value was significantly lower in patients at diagnosis (m = 7.1% versus m = 22.4% at relapse) and in patients who achieved a complete remission (m = 8.81% versus 31.5% in resistant cases). In the 22 samples analyzed, an overall correlation was found between the functional assay and the P-170 expression (r = 0.6), despite the much lower level of MDR positivity recognized by the immunocytometric method (m = 0.78% and 0.9% in cases at diagnosis versus m = 3.7% and 4.1% at relapse, with the 4E3.16 and MRK16 MoAbs). These data suggest that the assessment of the clinical impact of MDR expression in pediatric ALL should be based on methodological approaches capable of providing information extended to the P-170 pump function, rather then only on its gene and protein expression.

Allogeneic vs autologous BMT vs intensive chemotherapy in childhood AnLL during first complete remission: AIEOP experience. AIEOP Cooperative Group.

From 1982 to 1990, 340 children with newly diagnosed ANLL entered two consecutive AIEOP trials: LAM 8204 (1982-1987) and LAM 87 (1987-1990). Patients in both studies received identical remission induction with Daunorubicin and ARA-C. In the first study (LAM 8204) 167/171 patients were consolidated with four courses of DAT, followed by six additional courses of continuation therapy with three drug pairs given sequentially. Periodic intra-thecal ARA-C was used for CNS prophylaxis. For patients remaining on protocol, the OFS and EFS probability at 8 years was 35% and 30%, respectively. Induction response and EFS were adversely predicted by FAB MS subtype and hyperleukocytosis. In LAM 8204 trial there were 30 withdrawals represented by patients undergoing allogeneic (14) or autologous (16) BMT. For these patients the DFS probability at 5 years was 64% and 50%, respectively. On LAM-87 trial, 136/169 patients were evaluable and 98 (76%) attained CR. After consolidation with one course of DAT, patients with an HLA-identical donor underwent allogeneic BMT and those lacking a matched donor were randomized to receive either autologous BMT or the LAM 8204 postremission chemotherapy. The 2-year probability of DFS for allografted patients was 76% significantly higher (P = 0.0001) than that observed for patients on chemotherapy (12%) or autologous BMT (31%) arms.

Unrelated donor marrow transplantation for inborn errors.

From December 1989 to December 1997 40 children aged 1 year to 19 years with inborn errors other than severe combined immunodeficiencies underwent unrelated donor (UD) bone marrow transplantation (BMT) in one of 10 institutions of the Italian Bone Marrow Transplant Group participating in this program. The diseases leading to BMT included Fanconi Anemia (10), Thalassemia (8), Wiskott Aldrich syndrome (5), haemophagocytic lymphohystiocytosis (6), osteopetrosis (3), storage diseases (6), Chediak Higashi syndrome (1), Schwachman syndrome (1). Thirty-three pairs were A, B, DRB1 matched. Three pairs were one antigen mismatched and one pair was two antigens mismatched. The remaining three pairs lacked information on molecular biology. Twelve children underwent a preparative regimen including radiotherapy. The remaining 28 children were conditioned with a chemotherapy regimen which included Busulfan. GvHD disease prophylaxis included CSA and MTX alone (9) or associated with ALG (17) or in vivo Campath 1G (12). The remaining two children received CSA alone. Thirty-five children showed donor engraftment; three children with thalassemia and one with osteopetrosis failed to engraft. Five children developed secondary graft failure. Actuarial 5 year disease-free survival was 62%; grade III-IV acute GvHD developed in seven of 38 evaluable children (18%); chronic GvHD developed in seven of 27 evaluable children (26%). We confirm that Wiskott Aldrich syndrome, HLH, and osteopetrosis represent an absolute indication for UD-BMT. Prognosis of UD-BMT for FA could improve in children grafted in an early phase, but a better preparative regimen has to be identified. UD-BMT in thalassemia is acceptable only in a restricted subset of patients selected for poor compliance to therapy.