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Dive into the research topics where Tomas Ahlgren is active.

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Featured researches published by Tomas Ahlgren.


British Journal of Haematology | 2003

A validated decision model for treating the anaemia of myelodysplastic syndromes with erythropoietin + granulocyte colony-stimulating factor: significant effects on quality of life

Eva Hellström-Lindberg; Nina Gulbrandsen; Greger Lindberg; Tomas Ahlgren; Inger Marie S. Dahl; Ingunn Dybedal; Gunnar Grimfors; Eva Hesse‐Sundin; Martin Hjorth; Lena Kanter-Lewensohn; Olle Linder; Michaela Luthman; Eva Löfvenberg; Gunnar Öberg; Anja Porwit‐MacDonald; Anders Rådlund; Jan Samuelsson; Jon Magnus Tangen; Ingemar Winquist; Finn Wisløff

Summary. We have published previously a prototype of a decision model for anaemic patients with myelodysplastic syndromes (MDS), in which transfusion need and serum erythropoietin (S‐Epo) were used to define three groups with different probabilities of erythroid response to treatment with granulocyte colony‐stimulating factor (G‐CSF) + Epo. S‐Epo ≤ 500 U/l and a transfusion need of < 2 units/month predicted a high probability of response to treatment, S‐Epo > 500 U/l and ≥ 2 units/month for a poor response, whereas the presence of only one negative prognostic marker predicted an intermediate response. A total of 53 patients from a prospective study were included in our evaluation sample. Patients with good or intermediate probability of response were treated with G‐CSF + Epo. The overall response rate was 42% with 28·3% achieving a complete and 13·2% a partial response to treatment. The response rates were 61% and 14% in the good and intermediate predictive groups respectively. The model retained a significant predictive value in the evaluation sample (P < 0·001). Median duration of response was 23 months. Scores for global health and quality of life (QOL) were significantly lower in MDS patients than in a reference population, and fatigue and dyspnoea was significantly more prominent. Global QOL improved in patients responding to treatment (P = 0·01). The validated decision model defined a subgroup of patients with a response rate of 61% (95% confidence interval 48–74%) to treatment with G‐CSF + Epo. The majority of these patients have shown complete and durable responses.


Leukemia | 2002

Pooled analysis of clinical and cytogenetic features in treatment-related and de novo adult acute myeloid leukemia and myelodysplastic syndromes based on a consecutive series of 761 patients analyzed 1976–1993 and on 5098 unselected cases reported in the literature 1974–2001

Nils Mauritzson; Maria Albin; Lars Rylander; Rolf Billström; Tomas Ahlgren; Zoli Mikoczy; Jonas Björk; Ulf Strömberg; Per-Gunnar Nilsson; Felix Mitelman; L Hagmar; Bengt Johansson

To ascertain the frequency of treatment-related acute myeloid leukemias and myelodysplastic syndromes (t-AML/t-MDS) in an unselected series, we have identified all adult cases analyzed in our department from 1976 to 1993. Further aims were to compare karyotypic features of t-AML/t-MDS with de novo AML/MDS, in our material as well as in 5098 unselected, cyto- genetically abnormal, published cases, and to analyze associations between type of prior therapy and karyotype. Among our 372 AML and 389 MDS, 47 (13%) were t-AML and 62 (16%) were t-MDS. Clonal abnormalities were significantly more common in t-AML and t-MDS than in de novo disease (68% vs 50%, P < 0.05 and 84% vs 45%, P < 0.001, respectively). Among the available 4230 AML and 1629 MDS (the present series and published cases), 14% were t-AML and 15% were t-MDS. In t-AML/t-MDS, the number of anomalies and the ploidy levels differed significantly from de novo cases, with complex and hypodiploid karyotypes being more common in t-AML/t-MDS. In t-AML, unbalanced changes in general, t(1;3), der(1;7), 3p−, −5, 5q−, −7, 7q−, t(9;11), t(11;19), t(11q23), der(12p), −17, der(17p), −18, and −21 were significantly more frequent than in de novo AML. In t-MDS, −5, −7, 7q−, 13q−, der(17p), and −18 were significantly more common. Type of prior treatment correlated significantly with number of anomalies in t-AML and with ploidy levels in t-AML/t-MDS. The frequencies of several aberrations varied with type of therapy, eg, 5q− was more frequent in radiotherapy-associated t-MDS, monosomy 7 was more common in t-AML and t-MDS after treatment with alkylators, and t(11q23) in t-AML was associated with topoisomerase II inhibitors. Abnormalities significantly more common in de novo disease were +8 as a sole anomaly, balanced changes in general, t(8;21), t(9;22), t(15;17), inv(16), and t(21q22) in AML, and −Y, 5q−, and 20q− as sole anomalies and +8 in MDS. The results emphasize the strong association between previous genotoxic exposure and karyotypic features.


European Journal of Haematology | 2009

A single-center population-based consecutive series of 1500 cytogenetically investigated adult hematological malignancies: karyotypic features in relation to morphology, age and gender.

Nils Mauritzson; Bengt Johansson; Maria Albin; Rolf Billström; Tomas Ahlgren; Zoli Mikoczy; Per-Gunnar Nilsson; Lars Hagmar; Felix Mitelman

Abstract:  During the 18‐yr period 1976–93, a population‐based series of 1586 adults with suspected or confirmed hematological malignancies were successfully cytogenetically investigated at a single center. Eighty‐six cases were excluded due to unretrievable medical records or if analyzed only in remission or at relapse. The remaining 1500 medical records were reviewed regarding morphology and clinical parameters in order to investigate possible associations between karyotypic pattern (normal, 1, 2 or complex anomalies; specific abnormalities) and gender, age and morphological subgroups. The impact of time‐period, i.e. 1976–87 vs. 1988–93, and referring center on cytogenetic findings was also studied. A total of 372 acute myeloid leukemias (AML), 389 myelodysplastic syndromes (MDS), 64 acute lymphoblastic leukemias (ALL) and 262 chronic myeloid leukemias (CML) were identified, altogether 1087 cases. Patients with other (n = 261) or no hematological malignancies (n = 152) were excluded from the present analysis. Cytogenetic abnormalities were detected in 52% AML, 51% MDS, 68% ALL and 97% CML, frequencies that did not differ significantly between the 2 time periods or referring centers. No significant age‐ or gender‐related differences in karyotypic patterns were discerned in AML, MDS, ALL or CML, whereas the karyotypic patterns varied among the FAB groups in both AML (p = 0.001) and MDS (p< 0.001). The specific abnormalities t(8;21), t(15;17) and inv(16) were more common (p<0.001) in younger AML patients and 5q‐ was more frequent in females with MDS (p< 0.001). These findings indicate, in contrast to previous series, that neoplasia‐associated karyotypic aberrations are not more common among older patients or in males.


British Journal of Haematology | 1999

Prognostic evaluation in multiple myeloma: an analysis of the impact of new prognostic factors.

Ingemar Turesson; Niels Abildgaard; Tomas Ahlgren; Inger Marie S. Dahl; Erik Holmberg; Martin Hjorth; Johan Lanng Nielsen; A. Oden; Carina Seidel; Jan Westin; Finn Wisløff

We have analysed the prognostic information for survival of presenting features in an unselected series of 394 myeloma patients. 15 variables with significant prognostic information were identified, among these were some not previously or only recently reported: serum levels of hepatocyte growth factor (HGF), interleukin‐6 (IL‐6), C‐terminal cross‐linked telopeptide of collagen I (ICTP) and soluble interleukin‐6 receptor (sIL‐6R). In a multivariate Cox analysis six variables were significantly and independently associated with poor survival: high age, low W.H.O.‐performance status (PS), high serum levels of calcium, β‐2‐microglobulin (β‐2M), IL‐6 and sIL‐6R. A risk score formed to predict survival for each percentile of the patient population allowed an efficient separation of prognostic groups. The discriminating power of the model compared favourably with three other previously published staging systems applied to the study population. Exclusion of IL‐6 and sIL‐6R from the model only marginally decreased the efficacy of the separation. The predictive value of some variables (sIL‐6R, β‐2M and W.H.O.‐PS) decreased significantly over time. We conclude that formation of a risk score based on independent variables is an efficient way to separate prognostic groups, that the contribution of new and not easily available parameters should be thoroughly evaluated before inclusion in prognostic models for clinical use and that the predictive value of parameters may decrease over time.


Leukemia | 1997

Deletion of chromosome arm 3p in hematologic malignancies.

Bertil Johansson; Rolf Billström; Ulf Kristoffersson; Måns Åkerman; Stanislaw Garwicz; Tomas Ahlgren; Claes Malm; Felix Mitelman

Cytogenetic aberrations resulting in deletion of 3p are common in solid tumors, indicating the presence of tumor suppressor genes (TSG) on this chromosome arm. The present study was undertaken to investigate 3p loss in hematologic disorders. Ten acute myeloid leukemias (AML), two myelodysplastic syndromes (MDS), one Philadelphia chromosome-positive chronic myeloid leukemia (CML), three acute lymphoblastic leukemias (ALL), one chronic lymphoproliferative disorder (CLD), and three non-Hodgkin’s lymphomas (NHL) with abnormalities leading to 3p deletions were identified, constituting 2.9% of AML, 0.7% of MDS, 1.0% of CML with changes in addition to t(9;22), 1.5% of ALL, 4.2% of CLD, and 1.1% of NHL with cytogenetic abnormalities analyzed at our Department. Among 19042 karyotypically aberrant published cases, 1.2% of 6260 AML, 1.3% of 2285 MDS, 0.8% of 840 chronic myeloproliferative disorders (CMD), 0.7% of 1894 CML with additional aberrations to t(9;22), 0.6% of 3589 ALL 2.4% of 1602 CLD, 4.5% of 178 Hodgkin disease (HD), and 3.1% of 2394 NHL displayed partial loss of 3p (0.6–4.5%; P < 0.001); the majority occurring together with other abnormalities. the frequencies of 3p loss did not differ significantly among the mds, all, and cld morphologic subgroups, between b and t cell all, cld, and nhl, among low-, intermediate-, and high-grade nhl, or between therapy-related mds and de novo MDS, whereas the incidence of 3p deletions was higher in treatment-associated AML (P < 0.001) than in de novo AML and varied among the AML FAB groups (P < 0.001). the most frequently deleted chromosome bands were 3p25 in aml, 3p26 in mds, 3p14 in cmd, 3p25, 3p23, and 3p21 in cml, 3p26 and 3p25 in all, 3p26 and 3p25 in cld, 3p26 in hd, and 3p26 in nhl. these deletion hot spots are more distal than those reported in most solid tumor types, suggesting that different tsg are involved in hematologic malignancies and solid neoplasms.


European Journal of Haematology | 2009

Results of risk-adapted therapy in acute myeloid leukaemia. A long-term population-based follow-up study

Anders Wahlin; Rolf Billström; Ove Björ; Tomas Ahlgren; Michael Hedenus; Martin Höglund; Anders Lindmark; Berit Markevärn; Bo Nilsson; Bengt Sallerfors; Mats Brune

In 1997–2003, a protocol for treatment of acute myeloid leukaemia (AML) (except promyelocytic leukaemia) was activated in four Swedish health care regions covering 50% of the national population. Based on cytogenetics and clinical findings, patients aged 18–60 yr were assigned to one of three risk groups. In this report we account for the long‐term clinical outcome of enrolled patients. Patients received idarubicin and cytarabine in standard doses as induction therapy and consolidation courses included high‐dose cytarabine. Allogeneic stem cell transplantation (allo‐SCT) from an human leucocyte antigen‐identical sibling was recommended in standard and poor‐risk patients, whereas unrelated donor transplant was reserved for poor‐risk patients. Autologous (auto‐SCT) was optional for standard or poor risk patients not eligible for allo‐SCT. Two hundred seventy‐nine patients with de novo or secondary (9%) AML, median age 51 (18–60) yr, corresponding to 77% of all patients in the population, were included. Twenty (7%) patients were assigned to the good risk group, whereas 150 (54%) and 109 patients (39%) were assigned to standard‐ and poor‐risk groups, respectively. Induction failures accounted for 55 patients; 16 early deaths eight of whom had white blood cell (WBC) >100 at diagnosis, and 39 refractory disease. Thus, complete remission (CR) rate was 80%. At study closure, the median follow‐up time of living patients was 90 months. Median survival time from diagnosis in the whole group was 27 months and 4‐yr overall survival (OS) rate was 44%. In good, standard, and poor risk groups, 4‐yr OS rates were 60, 57 and 24%, respectively. Median relapse‐free survival (RFS) time in CR1 was 25 months and RFS at 4 yr was 44%. Four‐year RFS rates were significantly (P < 0.001) different between the three risk groups; 64% in good risk, 51% in standard risk and 27% in poor risk patients. One hundred‐ten transplantations were performed in CR1; 74 allo‐SCT (50 sibling, 24 unrelated donor), and 36 auto‐SCT. Non‐relapse mortality was 16% for allo‐SCT patients. Outcome after relapse was poor with median time to death 163 d and 4‐yr survival rate 17%. Three conclusions were: (i) these data reflect treatment results in a minimally selected population‐based cohort of adult AML patients <60 yr old; (ii) a risk‐adapted therapy aiming at early allogeneic SCT in patients with a high risk of relapse is hampered by induction deaths, refractory disease, and early relapses; and (iii) high WBC count at diagnosis is confirmed as a strong risk factor for early death but not for relapse.


British Journal of Haematology | 2003

Clinical and genetic studies of ETV6/ABL1-positive chronic myeloid leukaemia in blast crisis treated with imatinib mesylate

Aikaterini Barbouti; Tomas Ahlgren; Bertil Johansson; Mattias Höglund; Carin Lassen; Ingemar Turesson; Felix Mitelman; Thoas Fioretos

Summary. Most chronic myeloid leukaemia (CML) patients are genetically characterized by the t(9;22)(q34;q11), generating the BCR/ABL1 fusion gene. However, a few CML patients with rearrangements of 9q34 and 12p13, leading to ETV6/ABL1 chimaeras, have also been reported. Here we describe the clinical and genetic response to imatinib mesylate treatment of an ETV6/ABL1‐positive CML patient diagnosed in blast crisis (BC). A chronic phase was achieved after acute myeloid leukaemia induction therapy. Then, treatment with imatinib mesylate (600 mg/d) was initiated and the effect was assessed clinically as well as genetically, including by repeated interphase fluorescence in situ hybridization studies. Until d 71 of imatinib mesylate therapy, stable improvements in the clinical and laboratory features were noted, and the frequency of ABL1‐rearranged peripheral blood cells decreased from 56% to 11%. At d 92, an additional t(12;13)(p12;q13), with the 12p breakpoint proximal to ETV6, was found. The patient relapsed into BC 126 d after the start of the imatinib mesylate treatment and succumbed to the disease shortly afterwards. No mutations in the tyrosine kinase domain of ABL1 of the ETV6/ABL1 fusion were identified in the second BC. However, whereas the ETV6/ABL1 expression was seemingly the same at diagnosis and at second BC, the expression of ETV6 was markedly lower at the second BC. This decreased expression of wild‐type ETV6 may have been a contributory factor for the relapse.


Occupational and Environmental Medicine | 2001

Are occupational, hobby, or lifestyle exposures associated with Philadelphia chromosome positive chronic myeloid leukaemia?

Jonas Björk; Maria Albin; Hans Welinder; Håkan Tinnerberg; Nils Mauritzson; T Kauppinen; Ulf Strömberg; Bertil Johansson; Rolf Billström; Zoli Mikoczy; Tomas Ahlgren; Per-Gunnar Nilsson; Felix Mitelman; L Hagmar

OBJECTIVES To investigate a broad range of occupational, hobby, and lifestyle exposures, suggested as risk factors for Philadelphia chromosome positive (Ph+) chronic myeloid leukaemia (CML). METHODS A case-control study, comprising 255 Ph+CML patients from southern Sweden and matched controls, was conducted. Individual data on work tasks, hobbies, and lifestyle exposures were obtained by telephone interviews. Occupational hygienists assessed occupational and hobby exposures for each subject individually. Also, occupational titles were obtained from national registries, and group level exposure—that is, the exposure proportion for each occupational title—was assessed with a job exposure matrix. The effects of 11 exposures using individual data and two exposures using group data (organic solvents and animal dust) were estimated. RESULTS For the individual data on organic solvents, an effect was found for moderate or high intensity of exposure (odds ratio (OR) 3.4, 95% confidence interval (95% CI) 1.1 to 11) and for long duration (15–20 years) of exposure (OR 2.1, 95% CI 1.1 to 4.0). By contrast, the group data showed no association (OR 0.69, 95% CI 0.27 to 1.8; moderate or high intensity versus no exposure). For extremely low frequency electromagnetic fields (EMFs), only individual data were available. An association with long occupational exposure to EMFs was found (OR 2.3, 95% CI 1.2 to 4.5). However, no effect of EMF intensity was indicated. No significant effects of benzene, gasoline or diesel, or tobacco smoking were found. OR estimates below unity were suggested for personal use of hair dye and for agricultural exposures. CONCLUSIONS Associations between exposure to organic solvents and EMFs, and Ph+CML were indicated but were not entirely consistent.


Genes, Chromosomes and Cancer | 2000

RT-PCR analysis of the MOZ-CBP and CBP-MOZ chimeric transcripts in acute myeloid leukemias with t(8;16)(p11;p13)

Ioannis Panagopoulos; Margareth Isaksson; Charlotta Lindvall; Magnus Björkholm; Tomas Ahlgren; Thoas Fioretos; Sverre Heim; Felix Mitelman; Bertil Johansson

The translocation t(8;16)(p11;p13) is associated with a subtype of acute monocytic leukemia (AML M5) characterized morphologically by erythrophagocytosis and clinically by a poor prognosis. The t(8;16) fuses the MOZ gene from 8p11 with the CBP (also named CREBBP) gene from 16p13. Previously published studies of MOZ and CBP rearrangements in t(8;16)‐positive AML have used fluorescence in situ hybridization and Southern blot methodologies, whereas attempts to amplify and to analyze further the chimeric MOZ‐CBP and CBP‐MOZ transcripts by means of reverse transcriptase‐polymerase chain reaction (RT‐PCR) have largely been unsuccessful. In the only t(8;16) that has been described at the sequence level using RT‐PCR, the CBP‐MOZ fusion was found to be out‐of‐frame, suggesting that the reciprocal MOZ‐CBP transcript is the essential one for leukemogenesis. We have developed an RT‐PCR strategy that enables us to detect the MOZ‐CBP as well as the CBP‐MOZ fusions in the two AML M5 with t(8;16)(p11;p13) analyzed. In both leukemias, the combination of a MOZ forward and a CBP reverse primer amplified a strongly expressed 1,128 bp fragment (type I transcript) and a weakly expressed 415 bp fragment (type II transcript). In the type I transcript, nucleotide (nt) 3,745 of MOZ was fused in‐frame with nt 284 of CBP, whereas in the type II transcript, nt 3,745 of MOZ was fused out‐of‐frame with nt 997 of CBP. Nested PCR with a combination of two forward CBP and two reverse MOZ primers amplified CBP‐MOZ chimeric transcripts in both cases. Direct sequence analysis showed that nt 283 of CBP was fused in‐frame with nt 3,746 of MOZ, that the initiation ATG codon of the CBP gene remained intact, and that there was no mutation or deletion in the part of the CBP gene included in the CBP‐MOZ transcript. Thus, the data we present are not informative with regard to the question whether it is the MOZ‐CBP or the CBP‐MOZ transcript that is leukemogenic. The present RT‐PCR method may be of value for rapid identification of the t(8;16) and also for further molecular genetic studies of the two fusion transcripts and their roles in leukemogenesis. Genes Chromosomes Cancer 28:415–424, 2000.


Genes, Chromosomes and Cancer | 1999

Cytogenetic polyclonality in hematologic malignancies

Bertil Johansson; Rolf Billström; Karin Broberg; Thoas Fioretos; Per-Gunnar Nilsson; Tomas Ahlgren; Claes Malm; Bengt O. Samuelsson; Felix Mitelman

The present study was undertaken to ascertain the frequency of cytogenetic polyclonality in various hematologic malignancies and to investigate whether morphologic subgroup, age, gender, or previous genotoxic exposure influences the incidence. Among 2,243 cytogenetically investigated hematologic malignancies, 10 acute myeloid leukemias (AML), 5 myelodysplastic syndromes (MDS), 2 acute lymphoblastic leukemias (ALL), 1 acute undifferentiated leukemia (AUL), 1 atypical Philadelphia chromosome‐negative (Ph‐) chronic myeloid leukemia (CML), 1 chronic myeloproliferative disorder (CMD), and 1 chronic lymphoproliferative disorder (CLD) with karyotypically unrelated clones were identified, constituting 2.6% of AML, 1.6% of MDS, 0.8% of ALL, 13% of AUL, 9.1% of Ph‐ CML, 1.5% of CMD, and 2.8% of CLD with chromosomal abnormalities. In contrast to the cytogenetic features, the X‐inactivation pattern was monoclonal in the two informative female patients that could be investigated. Among 17,733 karyotypically aberrant published cases surveyed, significant frequency differences (P < 0.001) were discerned: 1.7% of 6,526 AML, 3.4% of 2,391 MDS, 0.4% of 1,920 Ph+ CML, 2.9% of 856 CMD, 0.9% of 4,226 ALL, and 5.8% of 1,814 CLD displayed unrelated clones. The incidence of cytogenetic polyclonality did not differ significantly among the MDS, CMD, or ALL subgroups, between males and females, between children (<16 years) and adults, or between B‐ and T‐cell ALL, whereas the frequencies varied among the AML FAB types (P < 0.05), among the different CLD entities (P < 0.001), and between B‐ and T‐cell CLD (P < 0.001). Furthermore, the incidence was higher in therapy‐related AML and MDS than in de novo AML and MDS (P < 0.001 and P < 0.01, respectively). Genes Chromosomes Cancer 24:222–229, 1999.

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