[Clinical research at the European LeukemiaNet].
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Publications and source records attributed to C Fonatsch.
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We investigated the pattern of lipoprotein lipase (LPL) expression in B-cell chronic lymphocytic leukemia (B-CLL) and assessed its prognostic relevance. Expression of LPL mRNA as well as protein was highly restricted to leukemic B cells. The intensity of intracellular immunoreactivity of LPL was higher in samples of patients with unmutated immunoglobulin heavy-chain variable region genes (IGV(H)) compared to those with mutated IGV(H) genes. LPL mRNA levels in peripheral blood mononuclear cells (PBMNC) from 104 CLL patients differed by 1.5 orders of magnitude between cases with mutated (N=51) or unmutated (N=53) IGV(H) (median: 1.33 vs 45.22 compared to normal PBMNC). LPL expression correlated strongly with IGV(H) mutational status (R=0.614; P<0.0001). High LPL expression predicted unmutated IGV(H) status with an odds ratio of 25.90 (P<0.0001) and discriminated between mutated and unmutated cases in 87 of 104 patients (84%). LPL expression was higher in patients with poor risk cytogenetics. High LPL expression was associated with a shorter treatment-free survival (median 40 vs 96 months, P=0.001) and a trend for a shorter median overall survival (105 months vs not reached). Our data establish LPL as a prognostic marker and suggest functional consequences of LPL overexpression in patients with B-CLL.
The international prognostic scoring system (IPSS) is considered the gold standard for risk assessment in primary myelodysplastic syndromes (MDS). This score includes several prognostic factors except serum lactate dehydrogenase (LDH). We evaluated the prognostic power of LDH as an additional variable in IPSS-based risk assessment. For this purpose, a total of 892 patients with primary MDS registered by the Austrian-German cooperative MDS study group was analyzed retrospectively. Multivariate analysis confirmed the value of established parameters such as medullary blasts, karyotype and peripheral cell counts and showed that elevated LDH was associated with decreased overall survival (P<0.00005) and increased risk of AML development (P<0.00005), independent of the system used to classify MDS (FAB or WHO). Moreover, elevated LDH was found to be a significant predictor of poor survival within each IPSS risk group and within each FAB group except RAEB-T. To exploit these results for refined prognostication, each IPSS risk group was split into two separate categories (A=normal LDH vs B=elevated LDH). Using this LDH-assisted approach, it was possible to identify MDS patients with unfavorable prognosis within the low and intermediate IPSS risk groups. We propose that the IPSS+LDH score should improve clinical decision-making and facilitate proper risk stratification in clinical trials.
According to the new WHO classification a group of chronic myeloproliferative diseases (CMPDs) were defined: chronic myeloid leukemia (CML), chronic neutrophilic leukemia (CNL), chronic eosinophilic leukemia and hypereosinophilic syndrome (CEL/HES), polycythemia vera (PV), chronic idiopathic myelofibrosis (with extramedullary hematopoiesis, CIMF), essential thrombocythemia (ET), and so called CMPD/unclassifiable. As clinical features and laboratory findings differ widely between these diseases several diagnostic approaches are mandatory at diagnosis for classification and are needed also for follow up studies, especially for the measurement of minimal residual disease (MRD). We here outline the laboratory set up at diagnosis and during follow up in CMPDs with specific focus on the respective therapeutical consequences. Only by using a comprehensive diagnostic panel including cytomorphology, cytogenetics, and molecular genetic methods establishing the correct diagnosis, optimizing treatment as well as evaluating treatment response is possible in CMPDs today.
Karyotype is an important prognostic factor in patients with newly diagnosed acute myeloblastic leukaemia (AML). The prognostic value of cytogenetics on the outcome of patients with AML in relapse has not yet been well defined. We analysed the clinical outcome of 152 patients with de novo, chemotherapy-treated AML in first relapse according to the cytogenetic classification of the United Kingdom Medical Research Council. The rate of second complete remission (CR) (88, 64 and 36%) and the probability of survival at 3 years (43, 18 and 0%) were significantly different between the favourable, intermediate and adverse cytogenetic risk groups, respectively. Compared to the favourable group, the relative risk (RR) of death (multivariate analyses) was 2.6 (confidence interval (CI): 1.5-4.4, P<0.001) for the intermediate and 3.7 (CI: 1.7-7.9, P=0.001) for the adverse group. The prognostic value of the duration of first CR was confirmed (RR of death: 2.0 (CI: 1.0-4.0) for each additional year in first CR), whereas the FLT3 mutation obtained at diagnosis did not markedly influence the outcome of patients with AML in relapse. In conclusion, our results indicate that both karyotype and the duration of first CR are independent prognostic factors for patients with de novo AML in first relapse.
Activation-induced cytidine deaminase (AID) is essential for somatic hypermutation of B-cells. We investigated the expression of AID mRNA by real-time polymerase chain reaction (PCR) in peripheral blood mononuclear cells of 80 patients with B-CLL. AID expression was detected in 45 of 80 patients (56%) at various levels, but was undetectable in 35 patients (44%). AID PCR positivity was associated with unmutated IGV(H) gene status (22 of 25 patients; P=0.002) and unfavourable cytogenetics (18 of 23 patients with deletion in 11q or loss of p53; P=0.040). Using a threshold level of 0.01-fold expression compared to Ramos control cells, even more significant associations were observed (P=0.001 for IGVH; P=0.002 for cytogenetics). A correlation was observed between individual AID levels and the percentage of V(H) homology (R=0.41; P=0.001). AID positivity predicted unmutated IGV(H) status with an odds ratio of 8.31 (P=0.003) and poor risk cytogenetics with an odds ratio of 3.46 (P=0.032). Significance was retained after adjustment for Binet or Rai stages. AID mRNA levels were stable over time. These data suggest a potential role of AID as a prognostic marker in B-CLL.
Bone marrow fibrosis (MF) has been shown to indicate therapy failure in Ph(+) chronic myeloid leukemia (CML). However, the results on the development of MF during interferon-alpha therapy of CML are controversial. The significance of the interferon dose has not been considered as yet. In total, 627 bone marrow biopsies taken prospectively from 200 patients with CML recruited in two studies using different doses of interferon-alpha +/- low-dose cytosine arabinoside were examined for MF before and during therapy. The results showed that the risk of MF depended significantly on the interferon-alpha dose applied (P<0.000005). MF progressed during low-dose therapy (3 x 5 x 10(6) IU/week), but was prevented from progression when applying high dose (5 x 10(6) IU/m(2)/per day). MF disappeared when high-dose interferon-alpha was combined with low-dose cytosine arabinoside (P<0.000005). The risk of death markedly increased when MF occurred or progressed (P<0.0009), independent of all other prognostic factors evaluated including the cytogenetic response. In conclusion, the effectiveness of interferon-alpha on MF depends on the treatment intensity. MF reverses when combining high-dose interferon-alpha with low-dose cytosine arabinoside, but progresses when applying low-dose interferon-alpha. MF appears to be a significant early indicator of ineffective therapy in CML.
We studied the incidence of leukemia cutis (LC) in 381 consecutive patients with acute myeloid leukemia (AML) in a single institution and compared the demographic, hematological, and cytogenetic findings in AML patients with and without LC. We also examined the response to intensive chemotherapy, overall survival, and duration of remission in this patient population with regard to the presence of LC. The prevalence of LC was 3.7% in clinically diagnosed patients and 2.9% in biopsy-proven cases, respectively. Patients with and without LC did not differ with regard to age, sex, white blood cell counts, hemoglobin, fibrinogen, and platelet counts at diagnosis, but lactate dehydrogenase (LDH) was significantly higher in patients with LC. Various karyotype abnormalities were found, but in patients with LC numerical abnormalities of chromosome 8 were significantly more common ( P<0.0001). Patients with LC did not differ from patients without LC with regard to remission rate, but there was a trend towards shorter remission duration in patients with LC. We conclude that patients with LC have some features different from patients without this symptom. The increased frequency of numerical aberrations of chromosome 8 in patients with LC was the most interesting observation of our study. The pathophysiological significance of this finding remains to be determined.
Hodgkin-Reed Sternberg cells are derived from germinal centre B-cells in most cases. Somatic mutations affecting their rearranged immunoglobulin genes were detected, rendering potential functional rearrangements non-functional. Under physiological conditions such cells would be designated to undergo apoptosis within the germinal centre. In search for the specific transforming event that prevents Hodgkin-Reed Sternberg cells from programmed cell death, cytogenetic analyses were broadly performed but did not reveal specific chromosomal aberrations. Analysis of these cells on the molecular level is difficult to perform due to the scarcity of the cells in the lymphoma tissue and the given limitations of in situ studies. To overcome these limitations, the cell line L1236, known to be derived from Hodgkin-Reed Sternberg cells in situ, was chosen for allelotype analysis. Using a panel of microsatellite loci assigned to nearly all chromosomal arms, regions of loss of heterozygosity were detected on chromosomal arms 6p, 9q and 17p. The size of lost segments was estimated by amplification of additional microsatellite loci mapped to the respective regions. Further analyses of single Hodgkin-Reed Sternberg cells will reveal whether LOH affecting these regions is a recurrent event in HD and to which extent the smallest commonly affected region can be estimated.
In the genesis of hematologic neoplasms gene amplification is a mechanism for illegitimate activation of proto-oncogenes. We report a phenotypically normal patient with a constitutional ring chromosome 21 who developed acute myeloid leukemia (AML). The leukemic cells revealed size-variable ring chromosomes 21 with amplification of the proto-oncogene AML1, located in the chromosomal band 21q22, within the rings. Hitherto, amplification of the proto-oncogene AML1-also in form of a ring chromosome-has been described recently only in one patient with myelodysplastic syndrome (MDS). In AML, gene amplification by ring formation has been demonstrated only in another three patients (amplification of the MLL gene in two cases and of the ETV6 gene in one case). Here we present the new evidence that the internal rearrangement of a constitutional ring chromosome 21 resulted in multiplication of a proto-oncogene in bone marrow cells and provided obviously a selective growth advantage. Moreover the amplification of ribosomal DNA was observed in the ring chromosomes of the tumor cells.
Gene amplification is a relatively rare event in acute myeloid leukemia (AML). Double minutes (dmin) and homogeneously staining regions are well established phenomena as cytogenetic correlates of gene amplification. Recently, however, two additional mechanisms leading to gene amplification, i.e., segmental jumping translocations and formation of ring chromosomes, have been described. We report four patients with AML, in whom bone marrow cells exhibited amplifications of ribosomal RNA (rRNA) genes in the form of ring chromosomes or a hsr. In two patients, the MLL gene, and in one patient the CBFA2 gene were shown to be co-amplified with rRNA genes. In two of the four patients, multiple copies of alpha-satellite sequences of the centromeres 13 and 21, respectively, were also demonstrated. In three of the four patients, the clinical course was very aggressive, leading to death within 2-8 months. In these three patients, complex karyotype abnormalities were found, whereas the karyotype of Patient 4 was characterized only by supernumerary ring 21 chromosomes of different sizes and a trisomy 8 in half of the metaphases. Modes of origin and clinical significance of the amplification of rRNA genes are discussed.
In myeloid malignancies, chromosome rearrangements involving band 3q21 are associated with a particularly poor prognosis of the disease. Their sensitive and unequivocal detection is therefore of great clinical importance. In this report, we describe the establishment of an interphase fluorescence in situ hybridization (FISH) assay that complements classical cytogenetic analysis in the diagnosis of such aberrations. PACs that map centromeric and telomeric of known 3q21 breakpoints were labeled with different fluorescent dyes, and the separation of the normally colocalizing signals was used as an indicator of the presence of a 3q21 rearrangement. Two cell lines and 10 primary samples from myeloid leukemia and myelodysplastic syndrome (MDS) patients with 3q21 rearrangements were investigated using the newly established method. The rate of false positivity was determined in 27 control samples from patients with various types of myeloid malignancies. In addition to providing a sensitive and rapid test for the detection of 3q21 aberrations, the interphase FISH assay yields preliminary information about the localization of individual breakpoints. Six of the 10 breakpoints in the patient samples map to an only recently described breakpoint cluster region (BCR) 60 kb centromeric of the originally reported 3q21 BCR. These findings may contribute to the understanding of the molecular basis of the clinical features associated with 3q21 rearrangements.
A number of prognostic scoring systems for patients with myelodysplastic syndromes (MDS) have been introduced in the past. In the present study, survival and AML evolution were analyzed retrospectively in a total of 180 patients with de novo MDS (observation period: 1989-1999; median age: 71; range 27-93; f/m ratio: 1/1.2). Diagnoses were established according to FAB criteria (RARS, n=37; RA, n=53; RAEB, n=50; RAEB-t, n=19; CMML, n=21). Six different multiparameter scoring systems (the Mufti, Aul, Sanz, Morel, and Toyama scores, and the international prognostic scoring system [IPSS]) were applied. The Aul, Sanz, and Mufti scores were applied to all 180 patients, Morel and Toyama scores to 109 patients, and the IPSS to 102. As assessed by multivariate analysis, the percentage of bm-blasts, hemoglobin, platelet count, neutrophil count, LDH, and karyotype were found to be independent single variables for survival, and bm-blasts, neutrophil count, platelet count, and karyotype for AML evolution. All prognostic scoring systems applied appeared to be highly predictive for survival and AML development (P<0.001). The highest predictive values were found for the Aul, Sanz, and Toyama scores for overall survival, and the IPSS, Toyama, and Morel scores for AML-free survival. In summary, our data show that scoring systems are useful for predicting overall and AML-free survival in patients with MDS. Karyotype-based multiparameter systems appear to be particularly effective in defining MDS patients who are at high risk of transforming to leukemia.
Several prognostic factors for patients with myelodysplastic syndromes (MDS) have been defined in the past. One of these factors appears to be the serum lactate dehydrogenase (LDH) activity. However, the precise predictive value of an elevated LDH level with regard to AML transformation remains uncertain. In this study, the prognostic value of the LDH activity was examined in a cohort of 180 patients with de novo MDS (median age 71 years [27-93]; f/m-ratio 1:1.2; RA: n=53; RARS: n=37; RAEB: n=50; RAEBT: n=19; CMML: n=21). Significant differences in LDH activities were found among FAB groups (P<0.05), and especially among IPSS groups (HIGH: 411+/-574; INT-2: 221+/-90; INT-1: 254+/-145; LOW: 192+/-47 U/l; P<0.05). An LDH level of >/=300 U/l was found to be associated with a significantly shorter median survival (10.3 months) when compared to <300 U/l (33.7 months; P<0.01). Moreover, an LDH activity of >/=300 U/l indicated a reduced AML-free survival in our MDS patients (P<0.01). As assessed by Cox regression, the inclusion of LDH as additional variable into the IPSS system resulted in an improved prediction concerning survival, but not with regard to AML evolution. Together, our data show that a serum LDH activity of >/=300 U/l in MDS is associated with a significantly shorter survival and higher risk to transform to AML. The LDH activity should be considered as an important prognostic factor in MDS.
The current study was undertaken to search for differences in the biology of cytogenetic subgroups in patients with de novo acute myeloid leukemia (AML). In addition, factors influencing the metabolism of cytosine arabinoside (araC) as the key agent of antileukemic activity were assessed. Bone marrow aspirates from 91 patients with newly diagnosed AML in whom karyotypes were successfully obtained were analyzed: (1) for spontaneous proliferative activity by 3H-thymidine (3H-TdR) incorporation; (2) proliferative response to GM-CSF by in vitro incubation of blasts for 48 h with or without GM-CSF (100 U/ml) followed by an additional 4-h exposure to 3H-TdR (0.5 microCi/ml); and (3) parameters of araC metabolism comprising 3H-araC uptake in vitro and the activities of polymerase alpha (poly alpha), deoxycytidine kinase (DCK) and deoxycytidine deaminase (DCD). According to the results of chromosome analyses four cytogenetic subgroups were discriminated: (I) normal karyotypes (n = 38); (II) favorable karyotypes [t8;21), t(15;17), inv(16)] (n = 16); (III) unfavorable karyotypes [inv (3), -5, 5q-, t(6;9), +8, t (9;11), complex abnormalities] (n = 20); (IV) karyotypes of unknown prognostic significance (n = 17). Proliferative activity of leukemic blasts was significantly higher in favorable karyotypes (group II) as compared to cases with unfavorable cytogenetics (group III) with median values and range for 3H-TdR uptake in group II of 2.48 pmol/10(5) cells (0.28-25.8) and in group III of 0.51 pmol/10(5) cells (0.04-7.6) (P = 0.0096). The respective values in group I and group IV were 0.7pmol/10(5) cells (0.0-6.7) and 0.98 pmol/10(5) cells (0.0-4.0), respectively. Inversely, response to GM-CSF, as defined by an increase in 3H-TdR incorporation >1.5- fold over control values after 48h of GM-CSF exposure, was significantly lower for patients with a favorable karyotype (group II) as compared to group I (P = 0.04) and group III (P = 0.013). No significant differences between karyotype groups I, II, III and IV were found for 3H-araC incorporation, nor for the activities of poly alpha, DCK and DCD. These data demonstrate differences in the biology of cytogenetic subgroups in AML which may partly explain the well established differences in clinical outcome.
We analyzed toxicity and efficacy of chemotherapy (CT) or second stem cell transplantation (SCT) and/or immunotherapy defined as stop of immunosuppression (IS) or donor leukocyte infusion (DLI) in 47 patients relapsing with acute leukemia. Ten patients received no treatment and 14 patients were treated with CT only. In 12 patients IS was stopped and three of them received additional CT. Five patients received DLI after CT as consolidation and one patient as frontline therapy. Five patients received a second SCT. Median overall survival after relapse was 2 months for the untreated patients, 2 months for patients receiving CT only, 2 months in patients after cessation of IS, 17 months in DLI treated patients and three months in patients receiving a second SCT. Fourteen patients achieved remission after relapse. Two with CT (2, 2 months), three with SI (3, 19, 19+ months), six with DLI (3, 8, 9, 14, 20, 36 months) and three with second SCT (2, 4, 6 months). Conventional CT was able do re-establish donor hematopoiesis and patients achieving remission showed a significantly better survival than patients with refractory disease. Patients who were brought into remission by DLI or cessation of IS had a significantly better survival than patients who achieved remission with CT alone or a second SCT. We conclude that a selected group of patients achieving remission with regeneration of donor hematopoiesis following CT might benefit from immunotherapy as consolidation.
The reliability of routine BCR-ABL RT-nested-PCR was evaluated in 1453 B-lineage ALL or hybrid leukemia at initial diagnosis by RT-nested-PCR. All BCR-ABL-positive (n = 642) and 176 BCR-ABL-negative samples underwent a second RT-PCR. In 518 patients, karyotyping and/or FISH was compared to the BCR-ABL status. The second RT-PCR revealed in 155/642 initially positive samples a divergent result (153 BCR-ABL-negative, two other transcripts) that in most cases turned out to be caused by contaminations in the first RT-nested-PCR. Confirmatory RT-PCR detected 2/176 false negative first RT-nested-PCR results. Thirty-nine specimens remained ambiguous despite different RT-PCR approaches. As far as cytogenetic evaluation and FISH is available (n = 23), the majority but not all patients with an ambiguous RT-PCR result were Ph-negative (n = 18). RT-nested-PCR and cytogenetics yielded in 346 of 383 evaluable samples a concordant result. Differing results are given and account in part to the lower sensitivity of karyotyping. Taken together, confirmed RT-PCR detected BCR-ABL fusion transcripts consistently in 487 out of 1453 ALL samples (c-ALL: 43%, pre-B ALL: 34%, pro-B ALL: 5%, B-ALL: 0%, hybrid leukemia: 5/11). Since false positive initial RT-nested-PCR data were frequent, either confirmatory second RT-PCR or FISH analysis is warranted to guarantee sensitive and reliable results of utmost clinical relevance.
The clinical significance of complex chromosome aberrations for adults with acute myeloid leukaemia (AML) was assessed in 920 patients with de novo AML who were karyotyped and treated within the German AML Cooperative Group (AMLCG) trials. Complex chromosome aberrations were defined as three or more numerical and/or structural chromosome aberrations excluding translocations t(8;21)(q22;q22), t(15;17)(q22;q11-q12) and inv(16)(p13q22). Complex chromosome anomalies were detected in 10% of all cases with a significantly higher incidence in patients > or = 60 years of age (17.8% vs. 7.8%, P < 0.0001). Clinical follow-up data were available for 90 patients. Forty-five patients were < 60 years of age and were randomly assigned to double induction therapy with either TAD-TAD [thioguanine, daunorubicin, cytosine arabinoside (AraC)] or TAD-HAM (high-dose AraC, mitoxantrone). Twenty-one patients achieved complete remission (CR) (47%), 20 patients (44%) were non-responders and 9% of patients died during aplasia (early death). The median overall survival (OS) was 7 months and the OS rate at 3 years was 12%. Patients receiving TAD-HAM showed a significantly higher CR rate than patients receiving TAD-TAD (56% vs. 23%, P = 0.04). Median event-free survival was less than 1 month in the TAD-TAD group and 2 months in the TAD-HAM group, respectively (P = 0.04), with a median OS of 4.5 months vs. 7.6 months (P = 0.13) and an OS after 3 years of 7.6% vs. 19.6%. Forty-five patients were > or = 60 years of age: 28 of these patient were treated for induction using one or two TAD courses and 17 cases received TAD-HAM with an age-adjusted reduction of the AraC dose. The CR rate was 44%, 38% were non-responders and 18% experienced early death. The median OS was 8 months and the OS rate at 3 years was 6%. In conclusion, complex chromosome aberrations in de novo AML predicted a dismal outcome, even when patients were treated with intensive chemotherapy. Patients under the age of 60 years with complex aberrant karyotypes may benefit from HAM treatment during induction. However, long-term survival rates are low and alternative treatment strategies for remission induction and consolidation are urgently needed.