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In this study, we analysed the prognostic relevance of foetal liver tyrosine kinase 3 (FLT3) mutations in 73 patients with acute myeloid leukaemia (AML) with normal karyotype, who survived induction and consolidation and received autologous stem cell transplantation (ASCT) after successful mobilization of peripheral blood stem cell (PBSC). There were 44 males and 29 females with a median age of 54 years (range 20-77). Overall, 16 out of 73 autografted patients (22%) had FLT3 mutations. More in detail, FLT3/ITDs were detected in 10 out of 73 patients (14%), while FLT3 D835 mutations were detected in five cases (7%). One patient (1%) was found as having both abnormalities. White blood cell count (p=0.009), serum concentration of lactate dehydrogenase (p=0.01), and percentages of peripheral blood (p=0.002) and bone marrow blasts (p=0.03) were significantly higher in patients showing the FLT3 mutations. On the contrary, overall survival and disease-free survival were similar between patients with or without FLT3 mutations (p=0.73 and 0.78, respectively). In conclusion, our data suggest that myeloablative chemotherapy supported by auto-PBSCT may overcome the adverse prognostic implications of FLT3 mutations in AML. However, it is to consider that autografted patients are highly selected for best response to induction, consolidation and mobilization, as well as for minor non-haematologic toxicity.

Fluorescence in situ hybridization and comparative genomic hybridization characterized 6p rearrangements in eight primary and in 10 secondary myeloid disorders (including one patient with Fanconi anemia) and found different molecular lesions in each group. In primary disorders, 6p abnormalities, isolated in six patients, were highly heterogeneous with different breakpoints along the 6p arm. Reciprocal translocations were found in seven. In the 10 patients with secondary acute myeloid leukemia/myelodysplastic syndrome (AML/MDS), the short arm of chromosome 6 was involved in unbalanced translocations in 7. The other three patients showed full or partial trisomy of the 6p arm, that is, i(6)(p10) (one patient) and dup(6)(p) (two patients). In 5/7 patients with unbalanced translocations, DNA sequences were overrepresented at band 6p21 as either cryptic duplications (three patients) or cryptic low-copy gains (two patients). In the eight patients with cytogenetic or cryptic 6p gains, we identified a common overrepresented region extending for 5-6 megabases from the TNF gene to the ETV-7 gene. 6p abnormalities were isolated karyotype changes in four patients. Consequently, in secondary AML/MDS, we hypothesize that 6p gains are major pathogenetic events arising from acquired and/or congenital genomic instability.

Despite progress in AML therapy, most patients eventually relapse, even the ones with normal or favorable karyotype. Since survival is poor once relapse occurs, new genetic tools above karyotype at diagnosis are needed to predict leukemia free survival. Recently, Flt3/ITD has been reported as an independent marker for clinical outcome in most studies concerning adult AML patients. To assess the prognostic relevance of activating mutations of Flt3, pretreatment samples of 100 not-M3 AML patients, all of them subjected to an intensive chemotherapy regimen, were analyzed for Flt3/ITD; 25/100 patients had one or more Flt3-ITD. Flt3/ITD patients had higher WBC count (P = 0.005), a lower incidence of a preceding MDS (P = 0.004) and most of them had a normal karyotype. Flt3/ITD had no impact on CR achievement while karyotype remained the most powerful prognostic factor (HR 2.8 95% CI 1.2 6.3). However, post-remission outcome was significantly worsened by the presence of Flt3/ITD. Median RFS of the Flt3/ITD patients was 5 vs. 27 months compared to the patients with wild-type Flt3 (P = 0.0002); moreover, Flt3/ITD patients had a significantly poorer post-remission survival (11 vs. 38 months, P = 0.01). On multivariate analysis, the presence of Flt3-ITD significantly affected relapse free survival and post-remission survival (HR 3.1 and 2.1, respectively). Thus, post-remission outcome highly depends on Flt3 status. Flt3 mutations identify patients at high risk of relapse, who should prospectively receive, according to age, either more aggressive or alternative therapeutic approaches.

The biological activity of MEN 11079, a new daunorubucin analogue with a fluorine atom in C(8) of ring A, was investigated in the human leukemic cell lines K-562 and in mononuclear cells (MNCs) of 40 patients with acute myeloid leukemia (AML) and the activity compared to two well-characterized anthracyclines, idarubicin (IDA) and doxorubicin (DOXO). IDA and MEN 11079 were more active than DOXO in cytotoxicity tests (WST-1 assay). IDA and MEN 11079 ID(50) values were also significantly different from each other (K-562: P=0.038; MNCs: P=0.003). Moreover, the range was 0.002-4.300 microM for IDA and 0.002-0.670 microM for MEN 11079, in the MNCs. Therefore, the latter appeared to assure a smaller variability of response in the AML cells. Apoptosis assays (performed using Annexin-V assay and propidium iodide) and cell cycle studies demonstrated that the MEN 11079 effective concentration was 10-fold lower than the DOXO and IDA ones. MDR (Pgp and MRP1 proteins), as measured by semiquantitative RT-PCR, cytofluorimetric and functional analysis of proteins, was similarly elicited by IDA and MEN 11079. In conclusion, the response of the cells to the new anthracycline indicates that there is greater cytotoxic activity of this molecule than IDA and DOXO. Its narrower ID(50) range may allow for a more predictable response in the clinical setting.

We studied the impact of cytogenetics and kind of induction/consolidation therapy on 848 adult acute myeloid leukemia (AML) patients (age 15-83). The patients received three types of induction/consolidation regimen: standard (daunorubicin and cytosine arabinoside (3/7); two cycles); intensive (idarubicin, cytosine arabinoside and etoposide (ICE), plus mitoxantrone and intermediate-dose Ara-C (NOVIA)); and low-dose (low-dose cytosine arabinoside). CR patients under 60 years of age, if an HLA-identical donor was available received allogeneic stem cell transplantation (allo-SCT); otherwise, as part of the program, they underwent autologous (auto)-SCT. CR rates significantly associated with 'favorable' (inv(16), t(8;21)), 'intermediate' ('no abnormality', abn(11q23), +8, del(7q)) and 'unfavorable' (del (5q), -7, abn(3)(q21q26), t(6;9), 'complex' (more than three unrelated cytogenetic abnormalities)) karyotypes (88% vs 65% vs 36%, respectively; P = 0.0001). These trends were confirmed in all age groups. On therapeutic grounds, intensive induction did not determine significant increases of CR rates in any of the considered groups, with respect to standard induction. Low-dose induction was associated with significantly lower CR rates. Considering disease-free survival (DFS), multivariate analysis of the factors examined (including karyotype grouping) showed that only age > 60 years significantly affected outcome. However, in cases where intensive induction was adopted, 'favorable' karyotype was significantly related to longer DFS (P = 0.04). This was mainly due to the favorable outcome of t(8;21) patients treated with intensive induction. Patients receiving allo-SCT had significantly longer DFS (P = 0.005); in particular, allo-SCT significantly improved DFS in the 'favorable' and 'intermediate' groups (P = 0.04 and P = 0.048, respectively). In conclusion our study could provide some guidelines for AML therapy: (1) patients in the 'favorable' karyotype group seem to have a longer DFS when treated with an intensive induction/consolidation regimen, adopted before auto-SCT instead of standard induction; this underlines the importance of reinforcement of chemotherapy, not necessarily based on repeated high-dose AraC cycles. Allo-SCT, independently of induction/consolidation therapy, should be considered an alternative treatment; (2) patients in the 'intermediate' karyotype group should receive allo-SCT; (3) patients in the 'unfavorable' karyotype group should be treated using investigational chemotherapy, considering that even allo-SCT cannot provide a significantly longer DFS, but only a trend to a better prognosis.

Acute myeloid disorders with rearrangements of 12p outside the ETV6 gene were characterized by fluorescence in situ hybridization (FISH) with a panel of DNA probes. Seven patients with de novo acute myeloid leukaemia (AML), one with secondary acute myeloid leukaemia (sAML), and one in the blast phase of chronic myeloid leukaemia (CML-BP) were enrolled in the study. All AML cases showed multiple karyotypic changes. Chromosome 5 and/or 7 deletions were the most frequent accompanying changes. FISH revealed amplification, cryptic translocation, and fragmentation of chromosome 12, not discernible at karyotypic level. Different karyotypic rearrangements of 12p showed a common molecular event. Among the seven cases in which breakpoints could be determined, six were telomeric and one centromeric to ETV6. In three AML cases a new recurrent breakpoint in the telomeric region was identified distally to locus D12S158 and to pac 922B22 which is the most telomeric probe available for 12p. Accompanying cryptic deletions were also detected in five patients and the commonly deleted region, of around 700 kb, included the ETV6 gene and the D12S391 locus.

Background and Objective: The best approach to treatment of acute myeloid leukemia (AML) in elderly patients remains controversial. Intensive chemotherapy is the treatment of choice in selected patients, but age related changes might affect the pharmacokinetics of antineoplastic agents resulting in enhanced toxicity. We report our experience in elderly patients treated with idarubicin at attenuated doses plus cytarabine and etoposide., Methods: Sixty-six AML patients, median age 66, with progressive disease and high tumor burden received idarubicin 8 mg/sqm i.v. d 1,3,5; cytarabine 200 mg/sqm by continuous i.v. infusion d 1-7; etoposide 60 mg/sqm i.v. d 1-5. A second course with the same drugs was planned irrespective of complete remission (CR) achievement. No consolidation was given; 44% had a documented preexisting myelodysplasia, 45% had a documented preexisting myelodysplasia, 45% presented with fever. Promyelocytic leukemias were excluded., Results: Thirty-five patients (53%) achieved CR and 9 PR for an overall response rate of 67%. Nine of them (13%) died early or during the aplastic phase. Preexisting myelodysplasia had no significant impact on CR achievement. Resistant disease was associated with CD7 phenotype and unfavorable karyotype. Overall survival and disease free survival were 14 and 13 months, respectively. The major toxicity consisted of infectious complications (WHO > 2 in 24% of patients). Six patients died for infection, 2 for heart failure, 1 for pulmonary embolism., Interpretation and Conclusions: This induction regimen with attenuated doses of idarubicin is feasible and effective, but long-term survival remains an unresolved problem. Alternative post remission approaches are advisable in the aim of improving the remission duration.

The results of treatment with low dose cytosine arabinoside (LDARA-C) in 131 AML patients ineligible for standard regimens were analyzed retrospectively. Eighty-seven were previously untreated, 25 were refractory to conventional chemotherapy and 19 were relapsed patients. The median age was 66 years (15-84). An antecedent hematological disorder (AHD) was documented in half of the patients. Overall, 22 (17%) achieved complete remission, 14 (11%) partial remission, 77 (59%) had resistant leukemia and 18 died during induction. Median disease free survival was 57 weeks and median survival, for the 87 previously untreated patients, was 22.5 weeks. The prognostic value of initial parameters was analyzed for response. Bone marrow cellularity was the only significant factor. We observed 33% vs 81% (p < 0.01) of responses in patients with normo-hypercellular and hypocellular marrow, respectively. Accordingly, there was a trend to more responses in patients with leukocyte counts of less than 10 x 10(9)/L. M4-M5 FAB subtypes were frequently resistant to LDARA-C, resulting in a lower response rate compared to M0-M2 (18% vs 32%). Other parameters, including age, sex, hemoglobin, platelet count, AHD and fever at diagnosis, had no prognostic value. Our findings suggest that LDARA-C may be an effective treatment for some patients who are not eligible for first line conventional chemotherapy. However, this schedule is not advised in patients with monocytic leukemia or those with an hypercellular marrow.

AML in the elderly is characterized by intrinsic biological features implying an enhanced chemoresistance. Intensive chemotherapy should be the treatment of choice, but the standard doses could induce unacceptable rates of aplastic deaths. We evaluated the efficacy of an induction protocol with attenuated-dose idarubicin (IDA) 8 mg/m2 for 3 d plus cytarabine and etoposide in 26 AML patients aged > 60. 18 patients (69%) achieved CR, five (19%) were non-responders and three (12%) died during induction. To compare the pharmacokinetics of IDA between elderly and young patients, we assayed daily the serum level of the drug and of its metabolite (idarubicinol, IDAol) in a group of eight elderly patients who received a dose of 8 mg/m2 (group A) and in a group of nine younger AML patients treated with 12 mg/m2 (group B). The apparent terminal half-life of IDAol was significantly longer in the elderly than in the younger patients (mean half-life 59.7 h versus 41.4 h, P < 0.05). The values of the area under the serum concentration curve of IDAol indicated that the two patient groups received a very similar exposure to the drug despite the different doses. In conclusion, this protocol, based on attenuated doses of IDA, compares well with the results obtained previously in similar age-matched patient series.