Efficacy of conventional-dose cytarabine, idarubicin and thioguanine versus intermediate-dose cytarabine and idarubicin in the induction treatment of acute myeloid leukemia: Long-term results of the prospective randomized nationwide AML-2003 study by the Finnish Leukemia Group.

OBJECTIVES: AML-2003 study sought to compare the long-term efficacy and safety of IAT and IdAraC-Ida in induction chemotherapy of acute myeloid leukemia (AML) and introduce the results of an integrated genetic and clinical risk classification guided treatment strategy. METHODS: Patients were randomized to receive either IAT or IdAraC-Ida as the first induction treatment. Intensified postremission strategies were employed based on measurable residual disease (MRD) and risk classification. Structured questionnaire forms were used to gather data prospectively. RESULTS: A total of 356 AML patients with a median age of 53 years participated in the study. Long-term overall survival (OS) and relapse-free survival (RFS) were both 49% at 10 years. The median follow-up was 114 months. No significant difference in remission rate, OS or RFS was observed between the two induction treatments. Risk classification according to the protocol, MRD after the first and the last consolidation treatment affected the OS and RFS significantly (p < .001). CONCLUSIONS: Intensified cytarabine dose in the first induction treatment was not better than IAT in patients with AML. Intensification of postremission treatment in patients with clinical risk factors or MRD seems reasonable, but randomized controlled studies are warranted in the future.

Molecular Monitoring after Autologous Stem Cell Transplantation and Preemptive Rituximab Treatment of Molecular Relapse; Results from the Nordic Mantle Cell Lymphoma Studies (MCL2 and MCL3) with Median Follow-Up of 8.5 Years.

The main objectives of the present study were to monitor minimal residual disease (MRD) in the bone marrow of patients with mantle cell lymphoma (MCL) to predict clinical relapse and guide preemptive treatment with rituximab. Among the patients enrolled in 2 prospective trials by the Nordic Lymphoma Group, 183 who had completed autologous stem cell transplantation (ASCT) and in whom an MRD marker had been obtained were included in our analysis. Fresh samples of bone marrow were analyzed for MRD by a combined standard nested and quantitative real-time PCR assay for Bcl-1/immunoglobulin heavy chain gene (IgH) and clonal IgH rearrangements. Significantly shorter progression-free survival (PFS) and overall survival (OS) was demonstrated for patients who were MRD positive pre-ASCT (54 patients) or in the first analysis post-ASCT (23 patients). The median PFS was only 20 months in those who were MRD-positive in the first sample post-ASCT, compared with 142 months in the MRD-negative group (P < .0001). OS was 75% at 10 years and median not reached in the MRD-negative group, compared with only 35 months in the MRD-positive group (P < .0001). Of the 86 patients (47%) who remained in continuous molecular remission, 73% were still in clinical remission after 10 years. For all patients, the median time from ASCT to first molecular relapse was 55 months, with a continuous occurrence of late molecular relapses. Fifty-eight patients who experienced MRD relapse received rituximab as preemptive treatment on 1 or more occasions, and in this group, the median time from first molecular relapse to clinical relapse was 55 months. In most cases, rituximab converted patients to MRD negativity (87%), but many patients became MRD-positive again later during follow-up (69%). By multivariate analysis, high-risk Mantle Cell Lymphoma International Prognostic Index score and positive MRD status pre-ASCT predicted early molecular relapse. In conclusion, preemptive rituximab treatment converts patients to MRD negativity and likely postpones clinical relapse. Molecular monitoring offers an opportunity to select some patients for therapeutic intervention and to avoid unnecessary treatment in others. MRD-positive patients in the first analysis post-ASCT have a dismal prognosis and thus are in need of novel strategies.

15-year follow-up of the Second Nordic Mantle Cell Lymphoma trial (MCL2): prolonged remissions without survival plateau.

In recent decades, the prognosis of Mantle Cell Lymphoma (MCL) has been significantly improved by intensified first-line regimens containing cytarabine, rituximab and consolidation with high-dose-therapy and autologous stem cell transplantation. One such strategy is the Nordic MCL2 regimen, developed by the Nordic Lymphoma Group. We here present the 15-year updated results of the Nordic MCL2 study after a median follow-up of 11·4 years: For all patients on an intent-to-treat basis, the median overall and progression-free survival was 12·7 and 8·5 years, respectively. The MCL International Prognostic Index (MIPI), biological MIPI, including Ki67 expression (MIPI-B) and the MIPI-B including mIR-18b expression (MIPI-B-miR), in particular, significantly divided patients into distinct risk groups. Despite very long response durations of the low and intermediate risk groups, we observed a continuous pattern of relapse and the survival curves never reached a plateau. In conclusion, despite half of the patients being still alive and 40% in first remission after more than 12 years, we still see an excess disease-related mortality, even among patients experiencing long remissions. Even though we consider the Nordic regimen as a very good choice of regimen, we recommend inclusion in prospective studies to explore the benefit of novel agents in the frontline treatment of MCL.

Nordic MCL3 study: 90Y-ibritumomab-tiuxetan added to BEAM/C in non-CR patients before transplant in mantle cell lymphoma.

The main objective of the MCL3 study was to improve outcome for patients not in complete remission (CR) before transplant by adding (90)Y-ibritumomab-tiuxetan (Zevalin) to the high-dose regimen. One hundred sixty untreated, stage II-IV mantle cell lymphoma patients <66 years received rituximab (R)-maxi-CHOP (cyclophosphamide, hydroxydaunorubicin, vincristine, and prednisone) alternating with R-high-dose cytarabine (6 cycles total), followed by high-dose BEAM/C (bis-chloroethylnitrosourea, etoposide, cytarabine, and melphalan or cyclophosphamide) and autologous stem cell transplantation from 2005 to 2009. Zevalin (0.4 mCi/kg) was given to responders not in CR before transplant. Overall response rate pretransplant was 97%. The outcome did not differ from that of the historic control: the MCL2 trial with similar treatment except for Zevalin. Overall survival (OS), event-free survival (EFS), and progression-free survival (PFS) at 4 years were 78%, 62%, and 71%, respectively. For responding non-CR patients who received Zevalin, duration of response was shorter than for the CR group. Inferior PFS, EFS, and OS were predicted by positron emission tomography (PET) positivity pretransplant and detectable minimal residual disease (MRD) after transplant. In conclusion, positive PET and MRD were strong predictors of outcome. Intensification with Zevalin may be too late to improve the outcome of patients not in CR before transplant. This trial was registered at www.clinicaltrials.gov as #NCT00514475.

Targeted resequencing of 9p in acute lymphoblastic leukemia yields concordant results with array CGH and reveals novel genomic alterations.

Genetic alterations of the short arm of chromosome 9 are frequent in acute lymphoblastic leukemia. We performed targeted sequencing of 9p region in 35 adolescent and adult acute lymphoblastic leukemia patients and sought to investigate the sensitivity of detecting copy number alterations in comparison with array comparative genomic hybridization (aCGH), and besides, to detect novel genetic anomalies. We found a high concordance of copy number variations (CNVs) as detected by next generation sequencing (NGS) and aCGH. By both methodologies, the recurrent deletion at CDKN2A/B locus was identified, whereas NGS revealed additional, small regions of CNVs, seen more frequently in adult patients, while aCGH was better at detecting larger CNVs. Also, by NGS, we detected novel structural variations, novel SNVs and small insertion/deletion variants. Our results show that NGS, in addition to detecting mutations and other genetic aberrations, can be used to study CNVs.

[Current treatment of acute leukemias in adults]. / Aikuisten akuuttien leukemioiden nykyhoito.

In addition to conventional microscopic morphology, immunophenotyping by flow cytometry as well as chromosome and molecular genetic studies are important methods in the diagnosis of acute leukemias. They are utilized for reaching a specific diagnosis, estimating the prognosis and looking for markers applicable to the examination of minimal residual disease. By means of combination chemotherapy and allogeneic stem cell transplantation more than 50% of patients under the age of 66 survive five years or more. The picture of the pathogenesis and behavior of leukemias is becoming clearer and new targets for drug therapy are being revealed.

Nordic MCL2 trial update: six-year follow-up after intensive immunochemotherapy for untreated mantle cell lymphoma followed by BEAM or BEAC + autologous stem-cell support: still very long survival but late relapses do occur.

Mantle cell lymphoma (MCL) is a heterogenic non-Hodgkin lymphoma entity, with a median survival of about 5 years. In 2008 we reported the early - based on the median observation time of 4 years - results of the Nordic Lymphoma Group MCL2 study of frontline intensive induction immunochemotherapy and autologous stem cell transplantation (ASCT), with more than 60% event-free survival at 5 years, and no subsequent relapses reported. Here we present an update after a median observation time of 6·5 years. The overall results are still excellent, with median overall survival and response duration longer than 10 years, and a median event-free survival of 7·4 years. However, six patients have now progressed later than 5 years after end of treatment. The international MCL Prognostic Index (MIPI) and Ki-67-expression were the only independent prognostic factors. Subdivided by the MIPI-Biological Index (MIPI + Ki-67, MIPI-B), more than 70% of patients with low-intermediate MIPI-B were alive at 10 years, but only 23% of the patients with high MIPI-B. These results, although highly encouraging regarding the majority of the patients, underline the need of a risk-adapted treatment strategy for MCL. The study was registered at www.isrctn.org as ISRCTN 87866680.

The Mantle Cell Lymphoma International Prognostic Index (MIPI) is superior to the International Prognostic Index (IPI) in predicting survival following intensive first-line immunochemotherapy and autologous stem cell transplantation (ASCT).

Mantle cell lymphoma (MCL) has a heterogeneous clinical course. The recently proposed Mantle Cell Lymphoma International Prognostic Index (MIPI) predicted the survival of MCL better than the International Prognostic Index in MCL patients treated with conventional chemotherapy, but its validity in MCL treated with more intensive immunochemotherapy has been questioned. Applied here to 158 patients of the Nordic MCL2 trial of first-line intensive immunochemotherapy followed by high-dose chemotherapy and autologous stem cell transplantation, the MIPI and the simplified MIPI (s-MIPI) predicted survival significantly better (P < .001) than the International Prognostic Index (P > .004). Both the MIPI and the s-MIPI mainly identified 2 risk groups, low and intermediate versus high risk, with the more easily applied s-MIPI being just as powerful as the MIPI. The MIPI(B) (biological), incorporating Ki-67 expression, identified almost half of the patients as high risk. We suggest that also a simplified MIPI(B) is feasible.

Focal 9p instability in hematologic neoplasias revealed by comparative genomic hybridization and single-nucleotide polymorphism microarray analyses.

Copy number losses in chromosome arm 9p are well-known aberrations in malignancies, including leukemias. The CDKN2A gene is suggested to play a key role in these aberrations. In this study overviewing 9p losses in hematologic neoplasias, we introduce the term focal 9p instability to indicate multiple areas of copy number loss or homozygous loss within a larger heterozygous one in 9p. We have used microarray comparative genomic hybridization to study patients with acute lymphoblastic leukemia (ALL, n = 140), acute myeloid leukemia (n = 50), chronic lymphocytic leukemia (n = 20), and myelodysplastic syndromes (n = 37). Our results show that 9p instability is restricted to ALL. In total, 58/140 (41%) patients with ALL had a loss in 9p. The 9p instability was detected in 19% of the patients with ALL and always included homozygous loss of CDKN2A along with loss of CDKN2B. Other possibly important genes included MTAP, IFN, MLLT3, JAK2, PTPLAD2, and PAX5. 13/27 (48%) patients with the instability had the BCR/ABL1 fusion gene or other oncogene-activating translocation or structural aberrations. Two patients had homozygous loss of hsa-mir -31, a microRNA known to regulate IKZF1. IKZF1 deletion at 7p12.1 was seen in 10 (37%) patients with the 9p instability. These findings suggest that, in ALL leukemogenesis, loss of CDKN2A and other target genes in the instability region is frequently associated with BCR/ABL1 and IKZF1 dysfunction. The multiple mechanisms leading to 9p instability including physical or epigenetic loss of the target genes, loss of the microRNA cluster, and the role of FRA9G fragile site are discussed.

Dasatinib crosses the blood-brain barrier and is an efficient therapy for central nervous system Philadelphia chromosome-positive leukemia.

Although imatinib, a BCR-ABL tyrosine kinase inhibitor, is used to treat acute Philadelphia chromosome-positive (Ph(+)) leukemia, it does not prevent central nervous system (CNS) relapses resulting from poor drug penetration through the blood-brain barrier. Imatinib and dasa-tinib (a dual-specific SRC/BCR-ABL kinase inhibitor) were compared in a preclinical mouse model of intracranial Ph(+) leukemia. Clinical dasatinib treatment in patients with CNS Ph(+) leukemia was assessed. In preclinical studies, dasatinib increased survival, whereas imatinib failed to inhibit intracranial tumor growth. Stabilization and regression of CNS disease were achieved with continued dasa-tinib administration. The drug also demonstrated substantial activity in 11 adult and pediatric patients with CNS Ph(+) leukemia. Eleven evaluable patients had clinically significant, long-lasting responses, which were complete in 7 patients. In 3 additional patients, isolated CNS relapse occurred during dasatinib therapy; and in 2 of them, it was caused by expansion of a BCR-ABL-mutated dasatinib-resistant clone, implying selection pressure exerted by the compound in the CNS. Dasatinib has promising therapeutic potential in managing intracranial leukemic disease and substantial clinical activity in patients who experience CNS relapse while on imatinib therapy. This study is registered at ClinicalTrials.gov as CA180006 (#NCT00108719) and CA180015 (#NCT00110097).

Long-term progression-free survival of mantle cell lymphoma after intensive front-line immunochemotherapy with in vivo-purged stem cell rescue: a nonrandomized phase 2 multicenter study by the Nordic Lymphoma Group.

Mantle cell lymphoma (MCL) is considered incurable. Intensive immunochemotherapy with stem cell support has not been tested in large, prospective series. In the 2nd Nordic MCL trial, we treated 160 consecutive, untreated patients younger than 66 years in a phase 2 protocol with dose-intensified induction immunochemotherapy with rituximab (R) + cyclophosphamide, vincristine, doxorubicin, prednisone (maxi-CHOP), alternating with R + high-dose cytarabine. Responders received high-dose chemotherapy with BEAM or BEAC (carmustine, etoposide, cytarabine, and melphalan/cyclophosphamide) with R-in vivo purged autologous stem cell support. Overall and complete response was achieved in 96% and 54%, respectively. The 6-year overall, event-free, and progression-free survival were 70%, 56%, and 66%, respectively, with no relapses occurring after 5 years. Multivariate analysis showed Ki-67 to be the sole independent predictor of event-free survival. The nonrelapse mortality was 5%. The majority of stem cell products and patients assessed with polymerase chain reaction (PCR) after transplantation were negative. Compared with our historical control, the Nordic MCL-1 trial, the event-free, overall, and progression-free survival, the duration of molecular remission, and the proportion of PCR-negative stem cell products were significantly increased (P < .001). Intensive immunochemotherapy with in vivo purged stem cell support can lead to long-term progression-free survival of MCL and perhaps cure. Registered at www.isrctn.org as #ISRCTN 87866680.

[Allogenic stem cell transplantations in lymphoma patients]. / Lymfoomapotilaiden allogeeniset kantasolujensiirrot.

The disease recurs in a significant proportion of lymphoma patients after the first-line treatment. Intensive treatment supported by the patient's own cells (autologic stem cell transplantation) has long been utilized in selected cases, but restrictions of this form of therapy are well known. Allogenic transplantation with another person's stem cells provides a possibility to treat lymphoma having a poor prognosis even in cases where other methods of treatments have failed. Allogeneic stem cell transplantation is, however, associated with a significant risk of death.

Itraconazole Increases Ibrutinib Exposure 10-Fold and Reduces Interindividual Variation-A Potentially Beneficial Drug-Drug Interaction.

The oral bioavailability of ibrutinib is low and variable, mainly due to extensive first-pass metabolism by cytochrome P450 (CYP) 3A4. The unpredictable exposure can compromise its safe and effective dosing. We examined the impact of itraconazole on ibrutinib pharmacokinetics. In a randomized crossover study, 11 healthy subjects were administered itraconazole 200 mg or placebo twice on day 1, and once on days 2-4. On day 3, 1 hour after itraconazole (placebo) and breakfast, ibrutinib (140 mg during placebo; 15 mg during itraconazole) was administered. Itraconazole increased the dose-adjusted geometric mean area under the concentration-time curve from zero to infinity (AUC0-∞ ) of ibrutinib 10.0-fold (90% confidence interval (CI) 7.2-13.9; P < 0.001) and peak plasma concentration (Cmax ) 8.8-fold (90% CI 6.3-12.1; P < 0.001). During itraconazole, the intersubject variation for the AUC0-∞ (55%) and Cmax (53%) was around half of that during placebo (104%; 99%). In conclusion, itraconazole markedly increases ibrutinib bioavailability and decreases its interindividual variability, offering a possibility to improved dosing accuracy and cost savings.

CDKN2A deletions in acute lymphoblastic leukemia of adolescents and young adults: an array CGH study.

Deletion in chromosome 9p involving the CDKN2A locus (9p21.3) is known in many malignancies. To detect this deletion in adolescent ALL patients we used oligo array CGH and studied 54 patients aged 10-25 years. Deletion rate was 25/54 (46%), of these 19/25 (76%) were homozygous. Small deletions (<200 kb) were found in 8/25 (32%) and the smallest deletion was <30 kb. The only gene affected in all deletions was CDKN2A. We were unable to demonstrate prognostic value of the deletion, however patients with deletion belonged more often (P=0.06) to unfavorable biological category. Our results indicate that CDKN2A deletions <200 kb may not be detected by conventional methods.

Acute lymphoblastic leukemia in adolescents and young adults in Finland.

BACKGROUND: Interest has recently been paid to adolescents and young adults with acute lymphoblastic leukemia, particularly because all reports so far published indicate that these patients have a better outcome when treated with pediatric rather than adult therapeutic protocols. There are different biological subtypes of acute lymphoblastic leukemia with distinct features and prognoses; the distribution of these subtypes is not well known among adolescents. We, therefore, studied acute lymphoblastic leukemia in adolescents and young adults aged 10 to 25 years in Finland. DESIGN AND METHODS: This population-based study included 225 consecutive patients aged 10-25 years diagnosed with acute lymphoblastic leukemia during 1990-2004. One hundred and twenty-eight patients (10-16 years) were treated with pediatric Nordic (NOPHO) protocols, and 97 patients (17-25 years) with Finnish Leukemia Group National protocols. We characterized the biological subtypes, clinical features and outcome of these patients. RESULTS: For the whole cohort, the remission rate was 96%, 5-year event-free survival 62% and overall survival 72%. The 5-year event-free survival was 67% for the pediatric treatment group and 60% for the adult treatment group (p=n.s.). Patients with inferior outcome were those with a white blood cell count >or= 100 x 10(9)/L, the Philadelphia chromosome and MLL. Good prognostic features were TEL-AML1, hyperdiploidy, and pediatric intermediate risk stratification. CONCLUSIONS: Unlike all previous studies, we found that the outcome of adolescents and young adults with acute lymphoblastic leukemia treated with pediatric or adult therapeutic protocols was comparable. The success of the adult acute lymphoblastic leukemia therapy emphasizes the benefit of central referral of patients to academic centers and adherence to research protocols.

Effect of fluconazole prophylaxis on the incidence of invasive candida infections and bacteraemias in patients with acute leukaemia.

OBJECTIVES: The efficacy of fluconazole prophylaxis to prevent invasive candida infections in patients with acute leukaemia receiving chemotherapy is not clear. Fluconazole prophylaxis might increase the number of bacteraemias and cause outbreaks of non-albicans yeast infections. A retrospective single-centre study was conducted to investigate the effect of fluconazole prophylaxis on the incidence and the species of invasive candida infections and on the number of bacteraemias. METHODS: All 1089 adult acute leukaemia patients treated with chemotherapy in 1978-2004 at Helsinki University Central Hospital were included. Data of positive blood cultures, histological samples, and fungal cultures was collected from the patient charts and the microbiology laboratory database. Fluconazole prophylaxis was used in all patients from 2000 on. RESULTS: Invasive candida infection was diagnosed in 74 out of 847 patients (8.7%) treated without fluconazole prophylaxis and in four out of 242 patients (1.6%) receiving the prophylaxis (P < 0.001). The incidence of non-albicans infections did not increase in the fluconazole prophylaxis group. A larger proportion of patients developed bacteraemias in the prophylaxis group (65%) compared to the non-prophylaxis group (52%) (P < 0.001). A trend towards more gram-positive bacteraemias was seen in the prophylaxis group. Invasive candida infections were more common in patients with acute lymphoblastic leukaemia than those with acute myeloid leukaemia, 10.5% vs. 5.9% (P = 0.008). CONCLUSIONS: Fluconazole prophylaxis was effective in preventing invasive candida infections in patients with acute leukaemia without increasing non-albicans infections. The risk of bacteraemias, however, increased.

A minor role of asparaginase in predisposing to cerebral venous thromboses in adult acute lymphoblastic leukemia patients.

Cerebral venous thrombosis (CVT) covers up to a third of all venous thromboses (VTs) detected in patients with acute lymphoblastic leukemia (ALL). It usually hampers patients' lives and may also endanger efficient leukemia treatment. Although many factors have been suggested to account for an elevated risk of VTs in patients with ALL, there still is a lack of studies focusing on CVTs and especially in the setting of adult ALL patients. We studied in our retrospective population-based cohort the occurrence, characteristics, as well as risk factors for VTs in 186 consecutively diagnosed Finnish adult ALL patients treated with a national pediatric-inspired treatment protocol ALL2000. In the risk factor analyses for VTs we found a distinction of the characteristics of the patients acquiring CVT from those with other kinds of VTs or without thrombosis. In contrast to previous studies we were also able to compare the effects of asparaginase in relation to CVT occurrence. Notably, more than half of the CVTs were diagnosed prior the administration of asparaginase which accentuates the role of other risk factors on the pathophysiology of CVT compared to truncal or central venous line (CVL) VTs in adult ALL patients.

Bloodstream infections in acute myeloid leukemia patients treated according to the Finnish Leukemia Group AML-2003 protocol - a prospective nationwide study.

BACKGROUND: Infections greatly influence the outcome of acute myeloid leukemia (AML) patients receiving intensive treatment. The aim of this study was to establish the incidence, microbial etiology, risk factors and prognosis of bloodstream infections (BSIs) in patients with AML and compare the results with the previous treatment protocol (AML-92). METHODS: Registery data were gathered prospectively from 357 patients aged 16-65 years recruited on the AML-2003 treatment protocol between November 2003 and November 2011 during different treatment cycles. RESULTS: Blood culture data were available on 977 treatment episodes, in which there were 503 BSIs (51%). The overall incidence rate (IR) for BSIs (per 1000 hospital days) was 16.7. Twenty patients (5.6%) died due to an infection and 16 of them (80%) had a BSI. The most commonly detected microbes (polymicrobial episodes included) in blood cultures were coagulase-negative staphylococci (CoNS, 24.7%), viridans group streptococci (VGS, 19.1%), enterococci (13.9%) and Enterobacteriacae group (25.9%). The etiology of BSIs varied greatly from treatment cycle to cycle. CONCLUSIONS: Enterococcal BSIs have increased compared to our previous treatment protocol, and they represent significant pathogens in blood cultures. Infection-related mortality has decreased despite the increase in the IR of BSIs. Enterococci seem to be an increasingly prominent pathogen underlying BSIs in the AML patients, especially during induction therapy (20%).