Daniela Silvestri

Molecular response to treatment redefines all prognostic factors in children and adolescents with B-cell precursor acute lymphoblastic leukemia: results in 3184 patients of the AIEOP-BFM ALL 2000 study

The Associazione Italiana di Ematologia Oncologia Pediatrica and the Berlin-Frankfurt-Münster Acute Lymphoblastic Leukemia (AIEOP-BFM ALL 2000) study has for the first time introduced standardized quantitative assessment of minimal residual disease (MRD) based on immunoglobulin and T-cell receptor gene rearrangements as polymerase chain reaction targets (PCR-MRD), at 2 time points (TPs), to stratify patients in a large prospective study. Patients with precursor B (pB) ALL (n = 3184) were considered MRD standard risk (MRD-SR) if MRD was already negative at day 33 (analyzed by 2 markers, with a sensitivity of at least 10(-4)); MRD high risk (MRD-HR) if 10(-3) or more at day 78 and MRD intermediate risk (MRD-IR): others. MRD-SR patients were 42% (1348): 5-year event-free survival (EFS, standard error) is 92.3% (0.9). Fifty-two percent (1647) were MRD-IR: EFS 77.6% (1.3). Six percent of patients (189) were MRD-HR: EFS 50.1% (4.1; P < .001). PCR-MRD discriminated prognosis even on top of white blood cell count, age, early response to prednisone, and genotype. MRD response detected by sensitive quantitative PCR at 2 predefined TPs is highly predictive for relapse in childhood pB-ALL. The study is registered at http://clinicaltrials.gov: NCT00430118 for BFM and NCT00613457 for AIEOP.

Risk of Relapse of Childhood Acute Lymphoblastic Leukemia Is Predicted By Flow Cytometric Measurement of Residual Disease on Day 15 Bone Marrow

PURPOSE Speed of blast clearance is an indicator of outcome in childhood acute lymphoblastic leukemia (ALL). Availability of measurement of minimal residual disease (MRD) at an early time point with a reduced-cost method is of clinical relevance. In the AIEOP-BFM-ALL (Associazione Italiana Ematologia Oncologia Pediatrica and Berlin-Frankfurt-Münster Study Group) 2000 trial, patients were stratified by levels of polymerase chain reaction (PCR) MRD at day +33 and +78. AIEOP studied the prognostic impact of MRD measured by flow cytometry (FCM) at day 15 of induction therapy. PATIENTS AND METHODS Bone marrow samples from 830 Italian patients were collected on day 15, after 14 days of steroids, and one dose of intrathecal methotrexate, vincristine, daunorubicine, and asparaginase. Cells were analyzed by four-color FCM for detection of leukemia-associated immunophenotypes. RESULTS Three patient risk groups were identified by FCM: standard (< 0.1% blast cells; 42% of the total), intermediate (0.1 to < 10%; 47%), and high (> or = 10%; 11%). Their 5-year cumulative incidences of relapse were 7.5% (SE, 1.5), 17.5% (SE, 2.1), and 47.2% (SE, 5.9), respectively. In multivariate analysis, FCM was the most important prognostic factor among those available by day 15, with two-fold and five-fold increase in the risk of relapse compared with patients with less than 0.1%. PCR MRD, when added to the model, had significant prognostic impact; yet high levels of FCM MRD retained an independent ability to detect a significantly higher risk of relapse. CONCLUSION Measurement of FCM MRD in day 15 bone marrow was the most powerful early predictor of relapse, applicable to virtually all patients; it may complement PCR MRD-based stratification including later time points, thus allowing additional treatment tailoring.

Long-term results of the Italian Association of Pediatric Hematology and Oncology (AIEOP) Studies 82, 87, 88, 91 and 95 for childhood acute lymphoblastic leukemia.

We analyzed the long-term outcome of 4865 patients treated in Studies 82, 87, 88, 91 and 95 for childhood acute lymphoblastic leukemia (ALL) of the Italian Association of Pediatric Hematology and Oncology (AIEOP). Treatment was characterized by progressive intensification of systemic therapy and reduction of cranial radiotherapy. A progressive improvement of results with reduction of isolated central nervous system relapse rate was obtained. Ten-year event-free survival increased from 53% in Study 82 to 72% in Study 95, whereas survival improved from 64 to 82%. Since 1991, all patients were treated according to Berlin-Frankfurt-Muenster (BFM) ALL treatment strategy. In Study 91, reduced treatment intensity (25%) yielded inferior results, but intensification of maintenance with high-dose (HD)-L-asparaginase (randomized) allowed to compensate for this disadvantage; in high-risk patients (HR, 15%), substitution of intensive polychemotherapy blocks for conventional BFM backbone failed to improve results. A marked improvement of results was obtained in HR patients when conventional BFM therapy was intensified with three polychemotherapy blocks and double delayed intensification (Study 95). The introduction of minimal residual disease monitoring and evaluation of common randomized questions by AIEOP and BFM groups in the protocol AIEOP-BFM-ALL 2000 are expected to further ameliorate treatment of children with ALL.

Poor prognosis for P2RY8-CRLF2 fusion but not for CRLF2 over-expression in children with intermediate risk B-cell precursor acute lymphoblastic leukemia

Pediatric B-cell precursor acute lymphoblastic leukemia (BCP-ALL) has achieved an 80% cure rate as a result of a risk-adapted therapy largely based on minimal residual disease (MRD) monitoring. However, relapse is still the most frequent adverse event, occurring mainly in the patients with intermediate MRD levels (intermediate risk, IR), emphasizing the need for new prognostic markers. We analyzed the prognostic impact of cytokine receptor-like factor 2 (CRLF2) over-expression and P2RY8-CRLF2 fusion in 464 BCP-ALL patients (not affected by Down syndrome and BCR-ABL negative) enrolled in the AIEOP-BFM ALL2000 study in Italy. In 22/464 (4.7%) samples, RQ-PCR showed CRLF2 over-expression (⩾20 times higher than the overall median). P2RY8-CRLF2 fusion was detected in 22/365 (6%) cases, with 10/22 cases also showing CRLF2 over-expression. P2RY8-CRLF2 fusion was the most relevant prognostic factor independent of CRLF2 over-expression with a threefold increase in risk of relapse. Significantly, the cumulative incidence of relapse of the P2RY8-CRLF2+ patients in the IR group was high (61.1%±12.9 vs 17.6%±2.6, P<0.0001), similar to high-risk patients in AIEOP-BFM ALL2000 study. These results were confirmed in a cohort of patients treated in Germany. In conclusion, P2RY8-CRLF2 identifies a subset of BCP-ALL patients currently stratified as IR that could be considered for treatment intensification.

Long-Term Results of the AIEOP-ALL-95 Trial for Childhood Acute Lymphoblastic Leukemia: Insight on the Prognostic Value of DNA Index in the Framework of Berlin-Frankfurt-Muenster–Based Chemotherapy

PURPOSE Between May 1995 and August 2000 the Associazione Italiana di Ematologia Oncologia Pediatrica conducted the ALL-95 study for risk-directed, Berlin-Frankfurt-Muenster (BFM) -oriented therapy of childhood acute lymphoblastic leukemia, aimed at exploring treatment reduction in standard-risk patients (SR) and intensification during continuation therapy in intermediate-risk patients (IR) as randomized questions and treatment intensification in high-risk patients (HR). The prognostic value of DNA index was explored in this setting. PATIENTS AND METHODS A total of 1,744 patients were enrolled (115, SR; 1,385, IR; and 244, HR). SR patients (DNA index >/= 1.16 and < 1.60; age, 1 to 5 years; and WBC < 20,000, non-T-immunophenotype, with no high-risk features) received a reduced induction therapy (no anthracyclines); IR patients were randomly assigned to receive or not receive vincristine and dexamethasone pulses during maintenance; HR therapy was based on a conventional BFM schedule intensified with three chemotherapy blocks followed by a double reinduction phase. RESULTS The event-free survival and overall survival probabilities at 10 years for the entire group were 72.5% (SE, 1.3) and 83.6% (SE, 0.9); 85.0% (SE, 3.4) and 95.5% (SE, 2.0) in SR, 75.1% (SE, 1.5) and 87.5% (SE, 0.9) in IR, and 51.0% (SE, 3.2) and 57.2% (SE, 3.3) in HR patients, respectively. Patients with a favorable DNA index had superior EFS in both IR (83.8% [2.7%] v 73.9% [1.7%]) and in HR (67.8% [9.4%] and 49.6% [3.5%]). Of the six patients with DNA index less than 0.8, only one remained in remission. CONCLUSION Favorable DNA index was associated with a better prognosis in IR and HR patients defined by presenting clinical criteria and treatment with a BFM-oriented chemotherapy.

FLT3 internal tandem duplication in childhood acute myeloid leukaemia: association with hyperleucocytosis in acute promyelocytic leukaemia

Summary. We evaluated the incidence of FLT3/internal tandem duplication (ITD) mutation in childhood acute myeloid leukaemia (AML) diagnosed over 15 years. FLT3/ITD was found in 10 of 45 (22·2%) non‐acute promyelocytic leukaemia (non‐APL) patients. The 5‐year event‐free survival of non‐APL patients was higher in FLT3/ITD‐negative versus ‐positive patients (48·9%, SE 8·9, vs 20·0%, SE 16·1, P = 0·03). In childhood APL, FLT3/ITD incidence was higher than in non‐APL, although not statistically significant (10 out of 29 patients, 34·5%, P = 0·29). In APL patients, FLT3/ITD was strongly correlated to a higher white blood cell count at diagnosis and the M3 French–American–British subtype.

What is the relevance of Ikaros gene deletions as a prognostic marker in pediatric Philadelphia-negative B-cell precursor acute lymphoblastic leukemia?

New prognostic markers are needed for upfront identification of patients with acute lymphocytic leukemia with a high risk of relapse or who are not likely to respond to the most aggressive chemotherapy. We focused our analysis on Ikaros (IKZF1) gene deletions in a homogeneous cohort of 410 pediatric patients with Philadelphia chromosome-negative, B-cell precursor acute lymphoblastic leukemia enrolled in Italy into the AIEOP-BFM ALL2000 study. We confirm their reported poor prognostic value, although the associated event-free survival was relatively high (approximately 70%). The difference in the cumulative incidence of relapse between patients positive or not for IKZF1 deletions was not marked: 24.2% (5.9) versus 13.1% (1.8) overall and 23.9% (6.6) versus 16.5% (2.5) in the intermediate-risk subgroup. In line with this, IKZF1 deletions were not an independent prognostic factor for the hazard of relapse. Most IKZF1-deleted cases stratified in the high-risk group relapsed, suggesting that once identified, patients with these deletions require an alternative treatment. In conclusion, the need of and benefit from introducing IKZF1 deletions as an additional stratification marker for patients with Philadelphia-negative B-cell precursor acute lymphoblastic leukemia remain questionable.

Minimal residual disease before and after transplantation for childhood acute lymphoblastic leukaemia: is there any room for intervention?

Eighty‐two children and adolescents who underwent allogeneic transplantation for acute lymphoblastic leukaemia in remission (period 2001–2011, median follow‐up 4·9 years) had been assessed for minimal residual disease (MRD) by real‐time quantitative polymerase chain reaction before and at 1, 3, 6, 9 and 12 months after transplantation. Five‐year event‐free survival (EFS) and cumulative incidence of relapse were 77·7% [standard error (SE) 5·7] and 11·4% (SE 4·4), respectively, for patients with pre‐transplant MRD <1 × 10−4 (68%), versus 30·8% (SE 9·1; P < 0·001) and 61·5% (SE 9·5; P < 0·001), respectively, for those with MRD ≥1 × 10−4 (32%). Pre‐transplant MRD ≥1 × 10−4 was associated with a 9·2‐fold risk of relapse [95% confidence interval (CI) 3·54–23·88; P < 0·001] compared with patients with MRD <1 × 10−4. Patients who received additional chemotherapy pre‐transplant to reduce MRD had a fivefold reduction of risk of failure (hazard ratio 0·19, CI 0·05–0·70, P = 0·01). Patients who experienced MRD positivity post‐transplant did not necessarily relapse (5‐year EFS 40·3%, SE 9·3), but had a 2·5‐fold risk of failure (CI 1·05–5·75; P = 0·04) if any MRD was detected in the first 100 d, which increased to 7·8‐fold (CI 2·2–27·78; P = 0·002) if detected after 6 months. Anticipated immunosuppression‐tapering according to MRD may have improved outcome, nevertheless all patients with post‐transplant MRD ≥1 × 10−3 ultimately relapsed, regardless of immunosuppression discontinuation or donor‐lymphocyte‐infusion. In conclusion, MRD before transplantation had the strongest impact on relapse and MRD positivity after transplantation, mostly if detected early and at low levels, did not necessarily imply relapse. Additional intensified chemotherapy and modulation of immunosuppression may reduce relapse risk and improve ultimate outcome.

Autologous bone marrow transplantation for treatment of isolated central nervous system relapse of childhood acute lymphoblastic leukemia

The purpose of this study was to assess the role of ABMT in children with ALL who are in 2nd CR after an early isolated CNS relapse. All children experiencing an isolated CNS relapse at 10 AIEOP centers (Associazione Italiana Emato-Oncologia Pediatrica) from 1986 to 1992 were eligible for this study. The series included 69 patients who relapsed within 3 years from diagnosis: 19 underwent ABMT, nine patients underwent ALLO-BMT from an HLA-identical sibling, and 41 received conventional chemotherapy (CHEMO). Statistical analysis was performed using a Cox’s regression model, adjusting for the waiting time before transplantation and prognostic factors. The 5 years DFS was 56.3% (s.e. 12.3) for patients in the ABMT group. This compared favorably with the poor result (12.6% (s.e. 5.9)) seen in the CHEMO group. The risk of failures was reduced by one-third in the ABMT group as compared to the CHEMO group in the multivariate analysis (P < 0.01). in the allo group four out of nine patients were in ccr 4–5 years post-transplant. this study suggests that abmt may also represent a valuable therapeutic choice for patients lacking a matched familiar donor in 2nd cr after an early isolated cns relapse.

Mechanical and infective central venous catheter-related complications: a prospective non-randomized study using Hickman and Groshong catheters in children with hematological malignancies

Abstract The aim of this study was to compare the Hickman and Groshong central venous catheters (CVCs) for incidence and severity of catheter-related complications in children. Seventy-three patients with hematological malignancies were observed, 42 with Groshong CVCs and 31 with Hickman CVCs. The number of infective episodes per 100 CVC-days was not significantly different (0.25 in the Hickman group versus 0.13 in the Groshong group;P=0.24). The most frequent type of CVC-related infection in both groups was microbiologically documented sepsis; in most cases Gram-positive bacteria were isolated. Neutropenia (P<0.001 for both CVCs) and hospital CVC management (P=0.0047 for the Hickman group, P<0.001 for the Groshong group) emerged as the major risk factors for the outbreak of infections. The rate of mechanical complication episodes per 100 CVC-days was similar in both groups (1.01 in the Hickman group versus 1.1 in the Groshong group;P=0.58). Some complications (fissures, ruptures, total lumen obstruction by clots) occurred only in the Groshong group. Our study did not demonstrate any statistically significant difference in the incidence of mechanical and infective CVC-related complications between these two types of catheter.