• Acute lymphoblastic leukemia and down syndrome: 6-mercaptopurine and methotrexate metabolites during maintenance therapy.

      Østergaard, Anna; Bohnstedt, Cathrine; Grell, Kathrine; Degn, Matilda; Zeller, Bernward; Taskinen, Mervi; Hafsteinsdottir, Solveig; Björgvinsdóttir, Helga; Heyman, Mats; Hoogerbrugge, Peter; et al. (Nature Publishing Group, 2020-07-04)
    • Asparaginase-associated pancreatitis: a study on phenotype and genotype in the NOPHO ALL2008 protocol.

      Wolthers, B O; Frandsen, T L; Abrahamsson, J; Albertsen, B K; Helt, L R; Heyman, M; Jónsson, Ó G; Kõrgvee, L T; Lund, B; Raja, R A; et al. (Nature Publishing Group, 2017-02)
      Asparaginase (ASP)-associated pancreatitis (AAP) occurs during acute lymphoblastic leukemia treatment. Among 1285 children (1.0-17.9 years) diagnosed during July 2008-December 2014 and treated according to the Nordic/Baltic ALL2008 protocol, 86 (cumulative incidence=6.8%) developed AAP. Seventy-three cases were severe (diagnostic AAP criteria persisting >72 h) and 13 mild. Cases were older than controls (median: 6.5 vs 4.5 years; P=0.001). Pseudocysts developed in 28%. Of the 20 re-exposed to ASP, 9 (45%) developed a second AAP. After a median follow-up of 2.3 years, 8% needed permanent insulin therapy, and 7% had recurrent abdominal pain. Germline DNA on 62 cases and 638 controls was genotyped on Omni2.5exome-8-v1.2 BeadChip arrays. Overall, the ULK2 variant rs281366 showed the strongest association with AAP (P=5.8 × 10(-7); odds ratio (OR)=6.7). Cases with the rs281366 variant were younger (4.3 vs 8 years; P=0.015) and had lower risk of AAP-related complications (15% vs 43%; P=0.13) compared with cases without this variant. Among 45 cases and 517 controls <10 years, the strongest associations with AAP were found for RGS6 variant rs17179470 (P=9.8 × 10(-9); OR=7.3). Rs281366 is located in the ULK2 gene involved in autophagy, and RGS6 regulates G-protein signaling regulating cell dynamics. More than 50% of AAP cases <10 years carried one or both risk alleles.
    • DNA-thioguanine concentration and relapse risk in children and young adults with acute lymphoblastic leukemia: an IPD meta-analysis.

      Toksvang, Linea N; Grell, Kathrine; Nersting, Jacob; Degn, Matilda; Nielsen, Stine N; Abrahamsson, Jonas; Lund, Bendik; Kanerva, Jukka; Jónsson, Ólafur G; Lepik, Kristi; et al. (Nature Publishing Group, 2021-06-26)
      Methotrexate/6-mercaptopurine maintenance therapy improves acute lymphoblastic leukemia (ALL) outcome. Cytotoxicity is mediated by DNA incorporation of thioguanine nucleotides (DNA-TG). We investigated the association of DNA-TG to relapse risk in 1 910 children and young adults with non-high risk ALL. In a cohort-stratified Cox regression analysis adjusted for sex, age, and white cell count at diagnosis, the relapse-specific hazard ratio (HRa) per 100 fmol/μg increase in weighted mean DNA-TG (wmDNA-TG) was 0.87 (95% CI 0.78-0.97; p = 0.013) in the 839 patients who were minimal residual disease (MRD) positive at end of induction therapy (EOI), whereas this was not the case in EOI MRD-negative patients (p = 0.76). Validation analysis excluding the previously published Nordic NOPHO ALL2008 pediatric cohort yielded a HRa of 0.92 (95% CI 0.82-1.03; p = 0.15) per 100 fmol/μg increase in wmDNA-TG in EOI MRD-positive patients. If also excluding the United Kingdom cohort, in which samples were taken non-randomly in selected patients, the HRa for the EOI MRD-positive patients was 0.82 (95% CI 0.68-0.99; p = 0.044) per 100 fmol/μg increase in wmDNA-TG. The importance of DNA-TG as a biomarker for maintenance therapy intensity calls for novel strategies to increase DNA-TG, although its clinical value may vary by protocol backbone.
    • Endothelial dysfunction and thromboembolism in children, adolescents, and young adults with acute lymphoblastic leukemia.

      Andrés-Jensen, Liv; Grell, Kathrine; Rank, Cecilie Utke; Albertsen, Birgitte Klug; Tuckuviene, Ruta; Linnemann Nielsen, Rikke; Lynggaard, Line Stensig; Jarvis, Kirsten Brunsvig; Quist-Paulsen, Petter; Trakymiene, Sonata Saulyte; et al. (Nature Publishing Group, 2021-08-13)
      Endothelial dysfunction has not previously been investigated as a thrombogenic risk factor among patients with acute lymphoblastic leukemia (ALL), known to be at high risk of thromboembolism. We retrospectively explored the association between three circulating biomarkers of endothelial dysfunction (thrombomodulin, syndecan-1, VEGFR-1) measured in prospectively collected blood samples and risk of thromboembolism in 55 cases and 165 time-matched controls, treated according to the NOPHO ALL2008 protocol. In age-, sex-, and risk group-adjusted analysis, increasing levels of thrombomodulin and VEGFR-1 were independently associated with increased odds of developing thromboembolism (OR 1.37 per 1 ng/mL [95% CI 1.20‒1.56, P < 0.0001] and OR 1.21 per 100 pg/mL [95% CI 1.02‒1.21, P = 0.005], respectively). These associations remained significant when including only samples drawn >30 days before thromboembolic diagnosis. Thrombomodulin levels were on average 3.2 ng/mL (95% CI 2.6-8.2 ng/mL) higher in samples with measurable asparaginase activity (P < 0.0001). Among single nucleotide variants located in or neighboring coding genes for the three biomarkers, none were significantly associated with odds of thromboembolism. If results are validated in another cohort, thrombomodulin and VEGFR-1 could serve as predictive biomarkers, identifying patients in need of preemptive antithrombotic prophylaxis.
    • The germline sequence variant rs2736100_C in TERT associates with myeloproliferative neoplasms.

      Oddsson, A; Kristinsson, S Y; Helgason, H; Gudbjartsson, D F; Masson, G; Sigurdsson, A; Jonasdottir, A; Jonasdottir, A; Steingrimsdottir, H; Vidarsson, B; et al. (Nature Publishing Group, 2014-06)
    • Improved long-term survival in multiple myeloma up to the age of 80 years.

      Kristinsson, S Y; Anderson, W F; Landgren, O; Karolinska Univ Hosp Solna, Dept Med, Div Hematol, Stockholm, Sweden, Karolinska Inst, Stockholm, Sweden, Univ Iceland, Fac Med, Reykjavik, Iceland, Landspitali Natl Univ Hosp, Dept Hematol, Reykjavik, Iceland, NCI, Div Canc Epidemiol & Genet, NIH, Bethesda, MD 20892 USA, NCI, Multiple Myeloma Sect, Metab Branch, Ctr Canc Res, Bethesda, MD 20892 USA (Nature Publishing Group, 2014-06)
    • Minimal residual disease quantification by flow cytometry provides reliable risk stratification in T-cell acute lymphoblastic leukemia.

      Modvig, S; Madsen, H O; Siitonen, S M; Rosthøj, S; Tierens, A; Juvonen, V; Osnes, L T N; Vålerhaugen, H; Hultdin, M; Thörn, I; et al. (Nature Publishing Group, 2019-06)
      Minimal residual disease (MRD) measured by PCR of clonal IgH/TCR rearrangements predicts relapse in T-cell acute lymphoblastic leukemia (T-ALL) and serves as risk stratification tool. Since 10% of patients have no suitable PCR-marker, we evaluated flowcytometry (FCM)-based MRD for risk stratification. We included 274 T-ALL patients treated in the NOPHO-ALL2008 protocol. MRD was measured by six-color FCM and real-time quantitative PCR. Day 29 PCR-MRD (cut-off 10-3) was used for risk stratification. At diagnosis, 93% had an FCM-marker for MRD monitoring, 84% a PCR-marker, and 99.3% (272/274) had a marker when combining the two. Adjusted for age and WBC, the hazard ratio for relapse was 3.55 (95% CI 1.4-9.0, p = 0.008) for day 29 FCM-MRD ≥ 10-3 and 5.6 (95% CI 2.0-16, p = 0.001) for PCR-MRD ≥ 10-3 compared with MRD < 10-3. Patients stratified to intermediate-risk therapy on day 29 with MRD 10-4-<10-3 had a 5-year event-free survival similar to intermediate-risk patients with MRD < 10-4 or undetectable, regardless of method for monitoring. Patients with day 15 FCM-MRD < 10-4 had a cumulative incidence of relapse of 2.3% (95% CI 0-6.8, n = 59). Thus, FCM-MRD allows early identification of patients eligible for reduced intensity therapy, but this needs further studies. In conclusion, FCM-MRD provides reliable risk prediction for T-ALL and can be used for stratification when no PCR-marker is available.
    • NT5C2 germline variants alter thiopurine metabolism and are associated with acquired NT5C2 relapse mutations in childhood acute lymphoblastic leukaemia.

      Tulstrup, Morten; Grosjean, Marie; Nielsen, Stine Nygaard; Grell, Kathrine; Wolthers, Benjamin Ole; Wegener, Peder Skov; Jonsson, Olafur Gisli; Lund, Bendik; Harila-Saari, Arja; Abrahamsson, Jonas; et al. (Nature Publishing Group, 2018-12-01)
      The antileukaemic drug 6-mercaptopurine is converted into thioguanine nucleotides (TGN) and incorporated into DNA (DNA-TG), the active end metabolite. In a series of genome-wide association studies, we analysed time-weighted means (
    • Results of NOPHO ALL2008 treatment for patients aged 1–45 years with acute lymphoblastic leukemia

      Toft, N; Birgens, H; Abrahamsson, J; Griškevičius, L; Hallböök, H; Heyman, M; Klausen, T W; Jónsson, ÓG; Palk, K; Pruunsild, K; et al. (Nature Publishing Group, 2017-09-22)
      Adults with acute lymphoblastic leukemia (ALL) do worse than children. From 7/2008 to 12/2014, Nordic and Baltic centers treated 1509 consecutive patients aged 1-45 years with Philadelphia chromosome-negative ALL according to the NOPHO ALL2008 without cranial irradiation. Overall, 1022 patients were of age 1-9 years (A), 266 were 10-17 years (B) and 221 were 18-45 years (C). Sixteen patients (three adults) died during induction. All others achieved remission after induction or 1-3 intensive blocks. Subsequently, 45 patients (12 adults) died, 122 patients relapsed (32 adults) with a median time to relapse of 1.6 years and 13 (no adult) developed a second malignancy. Median follow-up time was 4.6 years. Among the three age groups, older patients more often had higher risk ALL due to T-ALL (32%/25%/9%, P<0.001), KMT2A rearrangements (6%/5%/3%, P<0.001) and higher day 29 residual leukemia for B-lineage (P<0.001), but not T-ALL (P=0.53). Event-free survival rates (pEFS5y) were 89±1% (A), 80±3% (B) and 74±4% (C) with significant differences only for non-high risk groups. Except for thrombosis, pancreatitis and osteonecrosis, the risk of 19 specified toxicities was not enhanced by age above 10 years. In conclusion, a pediatric-based protocol is tolerable and effective for young adults, despite their increased frequency of higher risk features.
    • Second malignancies in patients with myeloproliferative neoplasms: a population-based cohort study of 9379 patients.

      Landtblom, Anna Ravn; Bower, Hannah; Andersson, Therese M-L; Dickman, Paul W; Samuelsson, Jan; Björkholm, Magnus; Kristinsson, Sigurdur Yngvi; Hultcrantz, Malin; 1 Department of Medicine, Division of Hematology, Stockholm South Hospital and Karolinska Institutet, Stockholm, Sweden. anna.ravn-landtblom@sll.se. 2 Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden. 3 Department of Medicine, Division of Hematology, Stockholm South Hospital and Karolinska Institutet, Stockholm, Sweden. 4 Department of Medicine, Division of Hematology, Karolinska University Hospital and Karolinska Institutet, Stockholm, Sweden. 5 Faculty of Medicine, University of Iceland and Department of Hematology, Landspitali National University Hospital, Reykjavik, Iceland. 6 Department of Medicine, Myeloma Service, Memorial Sloan-Kettering Cancer Center, New York, NY, USA. (Nature Publishing Group, 2018-10-01)
      To determine the risk of a wide range of second malignancies in patients with myeloproliferative neoplasms (MPNs), we conducted a large population-based study and compared the results to matched controls. From national Swedish registers, 9379 patients with MPNs diagnosed between 1973 and 2009, and 35,682 matched controls were identified as well as information on second malignancies, with follow-up until 2010. Hazard ratios (HRs) with 95 % confidence intervals (CIs) were calculated using Cox regression and a flexible parametric model. There was a significantly increased risk of any non-hematologic cancer with HR of 1.6 (95% CI: 1.5-1.7). The HRs for non-melanoma skin cancer was 2.8 (2.4-3.3), kidney cancer 2.8 (2.0-4.0), brain cancer 2.8 (1.9-4.2), endocrine cancers 2.5 (1.6-3.8), malignant melanoma 1.9 (1.4-2.7), pancreas cancer 1.8 (1.2-2.6), lung cancer 1.7 (1.4-2.2), and head and neck cancer 1.7 (1.2-2.6). The HR of second malignancies was similar across all MPN subtypes, sex, and calendar periods of MPN diagnosis. The risk of developing a hematologic malignancy was also significantly increased; the HR for acute myeloid leukemia was 46.0 (32.6-64.9) and for lymphoma 2.6 (2.0-3.3). In conclusion, our study provides robust population-based support of an increased cancer risk in MPN patients.
    • T-cell acute lymphoblastic leukemia in patients 1-45 years treated with the pediatric NOPHO ALL2008 protocol.

      Quist-Paulsen, P; Toft, N; Heyman, M; Abrahamsson, J; Griškevičius, L; Hallböök, H; Jónsson, Ó G; Palk, K; Vaitkeviciene, G; Vettenranta, K; et al. (Nature Publishing Group, 2019-10-14)
      The NOPHO ALL2008 is a population-based study using an unmodified pediatric protocol in patients 1-45 years of age with acute lymphoblastic leukemia. Patients with T-ALL were given a traditional pediatric scheme if fast responding (minimal residual disease (MRD) < 0.1% day 29), or intensive block-based chemotherapy if slow responding (MRD > 0.1% day 29). Both treatment arms included pediatric doses of high-dose methotrexate and asparaginase. If MRD ≥ 5% on day 29 or ≥0.1% after consolidation, patients were assigned to allogeneic hematopoietic stem cell transplantation. The 5-year overall survival of the 278 T-ALL patients was 0.75 (95% CI 0.69-0.81), being 0.82 (0.74-0.88) for patients 1.0-9.9 years, 0.76 (0.66-0.86) for those 10.0-17.9 years, and 0.65 (0.55-0.75) for the older patients. The risk of death in first remission was significantly higher in adults (12%) compared with the 1-9 years group (4%). The MRD responses in the three age groups were similar, and only a nonsignificant increase in relapse risk was found in adults. In conclusion, an unmodified pediatric protocol in patients 1-45 years is effective in all age groups. The traditional pediatric treatment schedule was safe for all patients, but the intensive block therapy led to a high toxic death rate in adults.
    • Value of flow cytometry for MRD-based relapse prediction in B-cell precursor ALL in a multicenter setting.

      Modvig, S; Hallböök, H; Madsen, H O; Siitonen, S; Rosthøj, S; Tierens, A; Juvonen, V; Osnes, L T N; Vålerhaugen, H; Hultdin, M; et al. (Nature Publishing Group, Specialist Journals, 2020-12-14)
      PCR of TCR/Ig gene rearrangements is considered the method of choice for minimal residual disease (MRD) quantification in BCP-ALL, but flow cytometry analysis of leukemia-associated immunophenotypes (FCM-MRD) is faster and biologically more informative. FCM-MRD performed in 18 laboratories across seven countries was used for risk stratification of 1487 patients with BCP-ALL enrolled in the NOPHO ALL2008 protocol. When no informative FCM-marker was available, risk stratification was based on real-time quantitative PCR. An informative FCM-marker was found in 96.2% and only two patients (0.14%) had non-informative FCM and non-informative PCR-markers. The overall 5-year event-free survival was 86.1% with a cumulative incidence of relapse (CIR5y) of 9.5%. FCM-MRD levels on days 15 (HzR 4.0, p < 0.0001), 29 (HzR 2.7, p < 0.0001), and 79 (HzR 3.5, p < 0.0001) associated with hazard of relapse adjusted for age, cytogenetics, and WBC. The early (day 15) response associated with CIR5y adjusted for day 29 FCM-MRD, with higher levels in adults (median 2.4 × 10-2 versus 5.2 × 10-3, p < 0.0001). Undetectable FCM- and/or PCR-MRD on day 29 identified patients with a very good outcome (CIR5y = 3.2%). For patients who did not undergo transplantation, day 79 FCM-MRD > 10-4 associated with a CIR5y = 22.1%. In conclusion, FCM-MRD performed in a multicenter setting is a clinically useful method for MRD-based treatment stratification in BCP-ALL.