Retinoic acid and arsenic trioxide for acute promyelocytic leukemia.

BACKGROUND: All-trans retinoic acid (ATRA) with chemotherapy is the standard of care for acute promyelocytic leukemia (APL), resulting in cure rates exceeding 80%. Pilot studies of treatment with arsenic trioxide with or without ATRA have shown high efficacy and reduced hematologic toxicity. METHODS: We conducted a phase 3, multicenter trial comparing ATRA plus chemotherapy with ATRA plus arsenic trioxide in patients with APL classified as low-to-intermediate risk (white-cell count, ≤10×10(9) per liter). Patients were randomly assigned to receive either ATRA plus arsenic trioxide for induction and consolidation therapy or standard ATRA-idarubicin induction therapy followed by three cycles of consolidation therapy with ATRA plus chemotherapy and maintenance therapy with low-dose chemotherapy and ATRA. The study was designed as a noninferiority trial to show that the difference between the rates of event-free survival at 2 years in the two groups was not greater than 5%. RESULTS: Complete remission was achieved in all 77 patients in the ATRA-arsenic trioxide group who could be evaluated (100%) and in 75 of 79 patients in the ATRA-chemotherapy group (95%) (P=0.12). The median follow-up was 34.4 months. Two-year event-free survival rates were 97% in the ATRA-arsenic trioxide group and 86% in the ATRA-chemotherapy group (95% confidence interval for the difference, 2 to 22 percentage points; P<0.001 for noninferiority and P=0.02 for superiority of ATRA-arsenic trioxide). Overall survival was also better with ATRA-arsenic trioxide (P=0.02). As compared with ATRA-chemotherapy, ATRA-arsenic trioxide was associated with less hematologic toxicity and fewer infections but with more hepatic toxicity. CONCLUSIONS: ATRA plus arsenic trioxide is at least not inferior and may be superior to ATRA plus chemotherapy in the treatment of patients with low-to-intermediate-risk APL. (Funded by Associazione Italiana contro le Leucemie and others; ClinicalTrials.gov number, NCT00482833.).

Cytotoxic effects of high concentrations of sodium ascorbate on human myeloid cell lines.

The effect of high doses of intravenous (sodium) ascorbate (ASC) in the treatment of cancer has been controversial although there is growing evidence that ASC in high (pharmacologic) concentrations induces dose-dependent pro-apoptotic death of tumor cells, in vitro. Very few data are available on the role of ASC in the treatment of acute myeloid leukemia (AML). Ascorbate behaves as an antioxidant at low (physiologic), and as pro-oxidant at pharmacologic, concentrations, and this may account for the differences reported in different experimental settings, when human myeloid cell lines, such as HL60, were treated with ASC. Considering the myeloid origin of HL60 cells, and previous literature reports showing that some cell lines belonging to the myeloid lineage could be sensitive to the pro-apoptotic effects of high concentrations of ASC, we investigated in more details the effects of high doses (0.5 to 7 mM) of ASC in vitro, on a variety of human myeloid cell lines including the following: HL60, U937, NB4, NB4-R4 (retinoic acid [RA]-resistant), NB4/AsR (ATO-resistant) acute promyelocytic leukemia (APL)-derived cell lines, and K562 as well as on normal CD34+ progenitors derived from human cord blood. Our results indicate that all analyzed cell lines including all-trans retinoic acid (ATRA)- and arsenic trioxide (ATO)-resistant ones are highly sensitive to the cytotoxic, pro-oxidant effects of high doses of ASC, with an average 50 % lethal concentration (LC50) of 3 mM, depending on cell type, ASC concentration, and time of exposure. Conversely, high doses of ASC neither did exert significant cytotoxic effects nor impaired the differentiation potential in cord blood (CB) CD34+ normal cells. Since plasma ASC concentrations within the millimolar (mM) range can be easily and safely reached by intravenous administration, we conclude that phase I/II clinical trials using high doses of ASC should be designed for patients with advanced/refractory AML and APL.

A phase II study of Givinostat in combination with hydroxycarbamide in patients with polycythaemia vera unresponsive to hydroxycarbamide monotherapy.

Givinostat, a histone-deacetylase inhibitor (HDACi), inhibits proliferation of cells bearing the JAK2 V617F mutation and has shown significant activity with good tolerability in patients with chronic myeloproliferative neoplasms (MPN). In this multicentre, open-label, phase II study, 44 patients with polycythaemia vera (PV), unresponsive to the maximum tolerated doses (MTD) of hydroxycarbamide (HC), were treated with Givinostat (50 or 100 mg/d) in combination with MTD of HC. The European LeukaemiaNet response criteria were used to assess the primary endpoint after 12 weeks of treatment. Complete or partial response was observed in 55% and 50% of patients receiving 50 or 100 mg of Givinostat, respectively. Control of pruritus was observed in 64% and 67% of patients in the 50 and 100 mg groups, respectively. The combination of Givinostat and HC was well tolerated: eight patients (18%) discontinued, four in each treatment arm; grade 3 adverse events were reported in one patient (4·5%) in each treatment arm. The combined use of Givinostat and HC was safe and clinically effective in HC-unresponsive PV patients.

AIDA 0493 protocol for newly diagnosed acute promyelocytic leukemia: very long-term results and role of maintenance.

All-trans-retinoic acid (ATRA) has greatly modified the prognosis of acute promyelocytic leukemia; however, the role of maintenance in patients in molecular complete remission after consolidation treatment is still debated. From July 1993 to May 2000, 807 genetically proven newly diagnosed acute promyelocytic leukemia patients received ATRA plus idarubicin as induction, followed by 3 intensive consolidation courses. Thereafter, patients reverse-transcribed polymerase chain reaction-negative for the PML-RARA fusion gene were randomized into 4 arms: oral 6-mercaptopurine and intramuscular methotrexate (arm 1); ATRA alone (arm 2); 3 months of arm1 alternating to 15 days of arm 2 (arm 3); and no further therapy (arm 4). Starting from February 1997, randomization was limited to ATRA-containing arms only (arms 2 and 3). Complete remission was achieved in 761 of 807 (94.3%) patients, and 681 completed the consolidation program. Of these, 664 (97.5%) were evaluated for the PML-RARA fusion gene, and 586 of 646 (90.7%) who tested reverse-transcribed polymerase chain reaction-negative were randomized to maintenance. The event-free survival estimate at 12 years was 68.9% (95% confidence interval, 66.4%-71.4%), and no differences in disease-free survival at 12 years were observed among the maintenance arms.

Health-related quality of life in chronic myeloid leukemia patients receiving long-term therapy with imatinib compared with the general population.

The main objective of this study was to investigate whether patients with chronic myeloid leukemia (CML) in treatment with long-term therapy imatinib have a different health-related quality-of-life (HRQOL) profile compared with the general population. In total, 448 CML patients were enrolled, and the SF-36 Health Survey was used to compare generic HRQOL profiles. Symptoms were also assessed. HRQOL comparisons were adjusted for key possible confounders. The median age of patients was 57 years and the median time of imatinib treatment was 5 years (range 3-9 years). The largest HRQOL differences were found in younger patients. In particular, patients aged between 18 and 39 years had marked impairments in role limitations because of physical and emotional problems, respectively: -22.6 (P < .001), -22.3 (P < .001). Patients with CML age 60 or older had a HRQOL profile very similar to that reported by the general population. Women had a worse profile than men when each were compared with their peers in the general population. Fatigue was the most frequently reported symptom. The HRQOL of CML patients is comparable with that of population norms in many areas, however, younger and female patients seem to report the major limitations.

Clinico-biological features of 5202 patients with acute lymphoblastic leukemia enrolled in the Italian AIEOP and GIMEMA protocols and stratified in age cohorts.

The outcome of children and adults with acute lymphoblastic leukemia is markedly different. Since there is limited information on the distribution of clinico-biological variables in different age cohorts, we analyzed 5202 patients with acute lymphoblastic leukemia enrolled in the Italian multicenter AIEOP and GIMEMA protocols and stratified them in nine age cohorts. The highest prevalence of acute lymphoblastic leukemia was observed in children, although a second peak was recorded from the 4(th) decade onwards. Interestingly, the lowest incidence was found in females between 14-40 years. Immunophenotypic characterization showed a B-lineage in 85.8% of patients: a pro-B stage, associated with MLL/AF4 positivity, was more frequent in patients between 10-50 years. T-lineage leukemia (14.2%) was rare among small children and increased in patients aged 10-40 years. The prevalence of the BCR/ABL1 rearrangement increased progressively with age starting from the cohort of patients 10-14 years old and was present in 52.7% of cases in the 6th decade. Similarly, the MLL/AF4 rearrangement constantly increased up to the 5(th) decade, while the ETV6/RUNX1 rearrangement disappeared from the age of 30 onwards. This study shows that acute lymphoblastic leukemia in adolescents and young adults is characterized by a male prevalence, higher percentage of T-lineage cases, an increase of poor prognostic molecular markers with aging compared to cases in children, and conclusively quantified the progressive increase of BCR/ABL(+) cases with age, which are potentially manageable by targeted therapies.

Front-line treatment of acute promyelocytic leukemia with AIDA induction followed by risk-adapted consolidation for adults younger than 61 years: results of the AIDA-2000 trial of the GIMEMA Group.

After the identification of discrete relapse-risk categories in patients with acute promyelocytic leukemia (APL) receiving all-trans retinoic and idarubicin (AIDA)-like therapies, the Gruppo Italiano Malattie Ematologiche dell'Adulto (GIMEMA) designed a protocol for newly diagnosed APL (AIDA-2000) in which postremission treatment was risk-adapted. Patients with low/intermediate risk received remission at 3 anthracycline-based consolidation courses, whereas high-risk patients received the same schedule as in the previous, non-risk-adapted AIDA-0493 trial including cytarabine. In addition, all patients in the AIDA-2000 received all-trans retinoic acid (ATRA) for 15 days during each consolidation. After induction, 600 of 636 (94.3%) and 420 of 445 (94.4%) patients achieved complete remission in the AIDA-0493 and AIDA-2000, respectively. The 6-year overall survival and cumulative incidence of relapse (CIR) rates were 78.1% versus 87.4% (P = .001) and 27.7% versus 10.7% (P < .0001). Significantly lower CIR rates for patients in the AIDA-2000 were most evident in the high-risk group (49.7% vs 9.3%, respectively, P < .0001). Our data confirm that anthracycline-based consolidation is at least equally effective as cytarabine-containing regimens for low-/intermediate-risk patients and suggest that a risk-adapted strategy including ATRA for consolidation improves outcome in newly diagnosed APL. Furthermore, our results highlight the role of cytarabine coupled to anthracyclines and ATRA during consolidation in the high-risk group.

Quality of life in elderly patients with essential thrombocythaemia. An Italian multicentre study.

Essential thrombocythaemia (ET) is a myeloproliferative neoplasm characterized by elevated platelet counts and increased incidence of thrombosis and haemorrhage. Median age at diagnosis is 65-70 years. Life expectancy is similar to that of the healthy population. Symptoms and complications may affect quality of life (QoL); in particular, in elderly patients ET may represent an additional burden. We performed a survey in 494 elderly ET patients to evaluate patient-reported outcomes (PROs). Comorbidities were present in 305 (62%) patients. Factorial analysis based on survey items representing psychological aspects of daily life identified an "attitude domain" with four clusters of patients: (A) very pessimistic (n = 99), (B) pessimistic (n = 101), (C) optimistic (n = 90), and (D) very optimistic (n = 107). Patients in cluster A had more comorbidities (p = 0.003) while patients in cluster D required fewer medical visits and were less disturbed by medications (p < 0.0001). Independent factors predicting Short-Form Health Survey, version 2 physical QoL were grade of optimism (p < 0.0001), gender (p = 0.007), and Charlson comorbidity index (p < 0.0001)). Grade of optimism and disturbances related to medication predicted mental QOL (p < 0.0001). In conclusion, physicians should take into consideration PROs, as "attitude" is associated with physical and mental QoL. Treatment should be tailored to patients' needs according to comorbidities, lifestyle, and psychological conditions.

Paroxysmal nocturnal hemoglobinuria after autologous stem cell transplantation: extinction of the clone during treatment with eculizumab - pathophysiological implications of a unique clinical case.

The clinical and biological spectrum of paroxysmal nocturnal hemoglobinuria (PNH) is variable, ranging from classical hemolytic forms to PNH associated with aplastic anemia or other bone marrow (BM) failure syndromes. We report a previously undescribed case of PNH occurring after autologous stem cell transplantation (ASCT) in a patient affected by relapsing non-Hodgkin's lymphoma. The intensive chemotherapy and the ASCT resulted in a contraction of the effective hematopoietic stem cell (HSC) pool and a derangement of the immune system. The delayed engraftment and the BM hypoplasia represented a favorable environment for the expansion of the pathological clone. This case is paradigmatic even for the unexpected trend of the PNH clone during treatment with the terminal complement inhibitor eculizumab; in fact, the clone reduced until undergoing unexpected extinction, i.e. the recovery of normal hematopoiesis. Eculizumab seems not to play a direct role in HSC kinetics; the clinical remission probably occurred because the environmental conditions that led to the expansion of the PNH clone were transient and disappeared.

Efficacy and safety of pegylated liposomal doxorubicin in primary cutaneous B-cell lymphomas and comparison with the commonly used therapies.

OBJECTIVES: The therapy of advanced, relapsed or refractory primary cutaneous lymphomas is often unsatisfactory. Recent data indicate a favourable pharmacokynetic, pharmacodynamic and toxicity profile of pegylated liposomal doxorubicin (Peg-Doxo) in primary cutaneous T-cell lymphomas, while in primary cutaneous B-cell lymphomas (PCBCLs), the drug efficacy has never been assessed so far. METHODS: We performed a prospective phase II pilot clinical trial of Peg-Doxo monotherapy (20 mg/m(2)) in PCBCLs. One patient had a marginal zone B-cell lymphoma and four were affected by diffuse large B-cell lymphoma-leg type, all with widespread nodular lesions. RESULTS: All the patients achieved a complete response (CR = 100%) in a short period of time (median 3 months), even when pretreated with radio-chemotherapy. Two experienced a relapse. At follow-up, one patient died for progressive disease; four are in CR after 5, 52, 63 and 69 months. As concerning the toxicity profile, the treatment was well-tolerated, no one decreased or delayed the dose. The haematological toxicity was mild with only one case of grade III neutropenia; a patient showed a grade I neurotoxicity. Dermatological toxicity, in particular the palmar-plantar erythrodysesthesia, did not occurred, probably because of both the low dosages of Peg-Doxo monotherapy and the oral prophylaxis with pyridoxine. CONCLUSIONS: In spite of the small number of patients, it emerges that monochemotherapy with Peg-Doxo has a significantly high clinical activity and a good safety profile in PCBCLs, even in aggressive forms, compared with other therapeutic regimens, which are completely reviewed. It suggests the need of further investigations in this field.

Voriconazole compared with liposomal amphotericin B for empirical antifungal therapy in patients with neutropenia and persistent fever.

BACKGROUND: Patients with neutropenia and persistent fever are often treated empirically with amphotericin B or liposomal amphotericin B to prevent invasive fungal infections. Antifungal triazoles offer a potentially safer and effective alternative. METHODS: In a randomized, international, multicenter trial, we compared voriconazole, a new second-generation triazole, with liposomal amphotericin B for empirical antifungal therapy. RESULTS: A total of 837 patients (415 assigned to voriconazole and 422 to liposomal amphotericin B) were evaluated for success of treatment. The overall success rates were 26.0 percent with voriconazole and 30.6 percent with liposomal amphotericin B (95 percent confidence interval for the difference, -10.6 to 1.6 percentage points); these rates were independent of the administration of antifungal prophylaxis or the use of colony-stimulating factors. There were fewer documented breakthrough fungal infections in patients treated with voriconazole than in those treated with liposomal amphotericin B (8 [1.9 percent] vs. 21 [5.0 percent], P=0.02). The voriconazole group had fewer cases of severe infusion-related reactions (P<0.01) and of nephrotoxicity (P<0.001). The incidence of hepatotoxicity was similar in the two groups. Patients receiving voriconazole had more episodes of transient visual changes than those receiving liposomal amphotericin B (22 percent vs. 1 percent, P<0.001) and more hallucinations (4.3 percent vs. 0.5 percent, P<0.001). Parenteral voriconazole was changed to the oral formulation in 22 percent of the voriconazole group, with a reduction in the mean duration of hospitalization by one day in all patients (P=0.17) but by two days in patients at high risk (P=0.03). CONCLUSIONS: Voriconazole is a suitable alternative to amphotericin B preparations for empirical antifungal therapy in patients with neutropenia and persistent fever.

Long-term remission in BCR/ABL-positive AML-M6 patient treated with Imatinib Mesylate.

BCR/ABL-positive acute myeloid leukemia (AML) is a rare disease, characterized by a poor prognosis, with resistance to induction chemotherapy and frequent relapses in responsive patients. Here we report a case of BCR/ABL-positive AML-M6 who, after relapse, was treated with Imatinib Mesylate (600 mg/die) and within 4 months achieved a cytogenetic and molecular complete response. After more than 4 years of continuous Imatinib therapy, nested RT-PCR for BCR/ABL is persistently negative. The case reported shows that the response obtained with Imatinib Mesylate in BCR/ABL-positive AML may be long lasting, offering a chance of successful treatment for this poor prognosis group of patients.

High-dose ascorbate and arsenic trioxide selectively kill acute myeloid leukemia and acute promyelocytic leukemia blasts in vitro.

The use of high-dose ascorbate (ASC) for the treatment of human cancer has been attempted several decades ago and has been recently revived by several in vitro and in vivo studies in solid tumors. We tested the cytotoxic effects of ASC, alone or in combination with arsenic trioxide (ATO) in acute myeloid leukemia (AML) and acute promyelocytic leukemia (APL). Leukemic cell lines and primary blasts from AML and APL patients were treated with graded concentrations of ASC, alone or in association with standard concentration (1 µM) of ATO. The ASC/ATO combination killed myeloid blasts, including leukemic CD34+ cells, while sparing CD34+ progenitors obtained from normal cord blood and bone marrow. Actually, approximately one-third (11/36) of primary AML cases were highly sensitive to the ASC/ATO combination. The mechanism of cell killing appeared to be related to increased oxidative stress and overproduction of ROS in a non-quantitative fashion, which resulted in induction of apoptosis. These effects were reverted by the addition of the antioxidant N-Acetyl-Cysteine (NAC). In the APL NB4 model, ASC induced direct degradation of the PML and PML/RARA proteins via caspase activation, while the transcriptional repressor DAXX was recruited in re-constituted PML nuclear bodies. Our findings encourage the design of pilot studies to explore the potential clinical benefit of ASC alone or in combination with ATO in advanced AML and APL.

Long-term follow-up of children treated for acute lymphoblastic leukemia and the recovery of beta-cell function.

We studied the evolution of beta-cell function in 32 children treated for acute lymphoblastic leukemia (ALL) through a long-term follow-up after completion of therapy. Our results show that although alterations of the glucose metabolism persists after stop-therapy they are reversible with time.

The role of BCR/ABL isoforms in the presentation and outcome of patients with Philadelphia-positive acute lymphoblastic leukemia: a seven-year update of the GIMEMA 0496 trial.

To verify the potential clinical and prognostic value of BCR/ABL isoforms, we analyzed 101 consecutive adult patients with Philadelphia chromosome-positive acute lymphoblastic leukemia enrolled in the GIMEMA 0496 trial between October 1996 and December 1999. A p190 or p210 with or without p190 BCR/ABL transcript was documented in 59 (58.5%) and 42 cases (41.5%), respectively. At diagnosis, a white cell count <16 x 10(9)/L and a higher level of CD34 and CD33 expression were associated with the p190 BCR/ABL transcript (p<0.05, p=0.009 and p=0.03, respectively). A complete remission was achieved in 62/92 (67.4%) patients, while 16/92 (17.4%) were resistant and 14/92 (15.2%) died of therapy-related complications. Fifty-two patients underwent intensive re-induction treatment, which was followed by stem cell transplant consolidation in the 36 in persistent complete remission (allogeneic = 20 patients; autologous = 16 patients). Response rates to induction therapies were similar in the two BCR/ABL isoform groups. By contrast, the p190 emerged as the only independent prognostic factor favorably affecting the 5-year overall survival and disease-free survival rates (p=0.008 and p=0.02, respectively).

Persistence of impaired pancreatic beta-cell function in children treated for acute lymphoblastic leukaemia.

Treatment for acute lymphoblastic leukaemia can induce alterations of glucose metabolism, but long-term follow-up data on this topic are still absent. We aimed to study glucose metabolism by intravenous and oral glucose tolerance testing in 32 children affected by acute lymphoblastic leukaemia and who were off-therapy for at least 1 year. 22 (69%) children presented with impaired first-phase insulin response, which in nine children was associated with impaired glucose tolerance and in one child with overt diabetes. Fasting insulin (4.65 mU/L, 95% CI 1.1-8.1; p=0.008), insulinogenic index (0.46; 0.02-0.98; p=0.03), and homoeostatic model assessment beta-cell function (80.1, 7.2-153; p=0.02) were reduced in the children with impaired insulin response. Chemotherapy for acute lymphoblastic leukaemia is associated with beta-cell function damage, which persists even after therapy has been stopped.

Philadelphia-positive acute lymphoblastic leukemia with multiple subclones including duplication of the Philadelphia chromosome and Abelson oncogene.

A case of Philadelphia (Ph)-positive acute lymphoblastic leukemia (ALL) with multiple subclones including duplication of the BCR-ABL1 fusion gene and of the Abelson oncogene (ABL1) is reported. Cytogenetically, two different rearrangements of chromosome 9 not involved in the t(9;22) were found in two subclones. In one subclone the normal 9 was lost and replaced by an acrocentric marker, which contained an additional copy of the BCR-ABL1 fusion gene. Reverse transcriptase polymerase chain reaction detected the fusion transcripts p210 (e13a2 junction) and p190 (e1a2 junction), whereas fluorescence in situ hybridization showed the major BCR-ABL1 junction in both Ph chromosomes, strongly suggesting that the presence of the p210 and p190 proteins in this case was due to mechanisms of alternative or mis-splicing at the transcriptional level. The second subclone showed the classic t(9;22) plus an add(9)(p24) containing two copies of the ABL1 gene. Other molecular events involving chromosome 9 were a monoallelic loss of JAK2 in both subclones and an additional loss of P15/P16 in the subclone with the acrocentric marker bearing the extra Ph chromosome.

Randomized phase III trial of retinoic acid and arsenic trioxide versus retinoic acid and chemotherapy in patients with acute promyelocytic leukemia: health-related quality-of-life outcomes.

PURPOSE: A randomized clinical trial compared efficacy and toxicity of standard all-trans-retinoic acid (ATRA) plus chemotherapy versus ATRA plus arsenic trioxide in patients with newly diagnosed, low- or intermediate-risk acute promyelocytic leukemia (APL). Here, we report health-related quality-of-life (HRQOL) results. PATIENTS AND METHODS: HRQOL was a secondary end point of this trial. The European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 was used to assess HRQOL at end of induction and after consolidation therapy. All analyses were based on 156 patients who received at least one dose of treatment, with groups defined according to randomly assigned treatment. Primary analysis was performed, estimating mean HRQOL score over time and differences between treatment arms using a linear mixed model. RESULTS: Overall, 162 patients age 18 to 70 years were enrolled. Of these, 150 and 142 patients were evaluable for HRQOL after induction therapy and third consolidation course, respectively. Overall compliance with HRQOL forms was 80.1%. The largest difference, favoring patients treated with ATRA plus arsenic trioxide, was found for fatigue severity (mean score difference, -9.3; 95% CI, -17.8 to -0.7; P = .034) at end of induction therapy. This difference was also clinically relevant. HRQOL differences between treatment arms at end of consolidation showed that for several scales, differences between treatment arms were marginal. CONCLUSION: Overall, current HRQOL findings further support the use of ATRA plus arsenic trioxide as preferred first-line treatment in patients with low- or intermediate-risk APL.

Brief Tale of a Bacteraemia by Rhodococcus equi, With Concomitant Lung Mass: What Came First, the Chicken or The Egg?

Rhodococcus equi is an uncommon Gram positive, variably acid-fast pathogen, that appears as hard to treat mostly owing to the establishment of intracellular niches. Lack of interpretive criteria for susceptibility testing may lead to under-reporting or overestimation of resistances, whereas knowledge about this pathogen's clinical impact may be affected by erroneous phenotype-based characterization at a genus and species level.We present the case of a bacteraemia with a concomitant lung mass in a lymphoma patient, that further highlights the emergence of rhodococcal diseases as a matter for concern in the fields of infectious diseases and haematology.

A simple prognostic scoring system for newly diagnosed cytogenetically normal acute myeloid leukemia: retrospective analysis of 530 patients.

We retrospectively analyzed the data of 337 patients with cytogenetically normal (CN) acute myeloid leukemia (AML), aged ≤ 65 years (training set). A prognostic index score (PIS) was calculated by totaling the score derived from the regression coefficients of each clinical variable, significantly associated with prognosis by multivariate analysis. The variables that were independent prognostic factors for event-free survival (EFS) and overall survival (OS) in the training set were: age ≥ 50 years, secondary AML and white blood cell count (WBC) ≥ 20 × 10(9)/L. The patients of the training set were stratified into three groups: low-, intermediate- and high-risk. The median EFS was 25, 12 and 7 months in the low-, intermediate- and high-risk groups (p < 0.0001), respectively. The median OS was not reached in the low-risk group and was 19 and 10 months in the intermediate- and high-risk groups (p < 0.0001). This PIS was validated in a series of 193 patients with CN-AML. The median EFS was 66, 16, and 3 months (p < 0.0001) and the median OS was 66, 16, and 5 months in the three risk groups, respectively (p < 0.0001). This PIS may be useful for clinical decision-making in CN-AML and may be prospectively integrated with the newest biological markers which at present are not routinely assessed and need prognostic validation.