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W Hiddemann

Publications and source records attributed to W Hiddemann.

At least 163 records · Page 9Linked to original sources

Hypercoagulability in a patient with hypodysfibrinogenemia: implications for clinical management.

Dysfibrinogenemia accounts for approximately 0.7% of thrombophilia in patients with venous thromboembolic disease. In 20% of these patients, plasma thrombophilic dysfibrinogen is below 1.0 mg/ml, defining hypodysfibrinogenemia. We describe a young female patient, in whom hypodysfibrinogenemia was the cause of several severe thromboembolic events which occurred even under oral anticoagulation monitored by a standard prothrombin time (PT) test. In this patient, the standard PT test according to Quick underestimated the plasma coagulability in vivo, presumably due to the low levels of dysfunctional fibrinogen as the substrate of the thromboplastin reagent. A PT test supplemented with bovine plasma fibrinogen (Thrombotest) revealed lower fibrinogen-independent international normalized ratio (INR) values in the proposita on oral anticoagulation compared to a control group with eufibrinogenemia. Monitoring therapy with the fibrinogen-independent Thrombotest secured safe anticoagulation in this patient. We suggest to consider PT tests with exogenous fibrinogen (e.g. Thrombotest) to monitor oral anticoagulation in the rare thrombophilic patients with hypodysfibrinogenemia.

Adult↗

Management of acute myeloid leukemia in elderly patients.

Acute myeloid leukemia (AML) at older age is associated with several biologic and clinical characteristics. Hence, it may arise from an early level of hematopoietic stem cells and has a high frequency of blast cells with multidrug resistance glycoprotein MDR1 expression and particularly a high incidence of poor prognostic karyotypes. These factors, rather than age per se, underlie the poorer outcome as compared with younger cases. Prospective randomized studies clearly demonstrate, however, that elderly patients benefit from more intensive induction therapy and particularly from full-dose application of anthracyclines and possibly also cytarabine. Hematopoietic growth factors accelerate the recovery from treatment-induced neutropenia and may improve the remission rate, remission duration, and even overall survival. New treatment strategies need to be developed, however, for poor-prognosis AML subtypes in order to further improve the therapeutic perspectives for elderly patients with AML.

Aged↗

Gemcitabine as a single agent in the treatment of relapsed or refractory aggressive non-Hodgkin's lymphoma.

PURPOSE: A multicenter phase II trial was conducted to evaluate the efficacy and toxicity of gemcitabine in patients with relapsed or refractory aggressive non-Hodgkin's lymphomas (NHL). PATIENTS AND METHODS: Thirty-one patients with B-cell intermediate or high-grade NHL (Working Formulation) were enrolled onto the study. The median age was 61 years, with a Karnofsky performance status of </= 80% in 65% of patients. Forty-eight percent had stage III or IV (Ann Arbor Classification) at study entry. Pretreatment consisted of one, two, or three chemotherapeutic regimens in nine, 11, and 11 patients, respectively. Gemcitabine 1,250 mg/m(2) was administered intravenously over 30 minutes on days 1, 8, and 15 of a 28-day schedule. RESULTS: Thirty patients were assessable for efficacy, and 31 were assessable for toxicity. No complete responses were observed, but six patients showed a partial response, 11 stable disease, and 13 progressive disease. The overall response rate was 20% (95% confidence interval, 8% to 39%) for assessable patients and 19% (95% confidence interval, 8% to 34%) for the intent-to-treat analysis. The median duration of partial response was 6 months (range, 3.7 to 15+ months). Nonhematologic World Health Organization grade 3 toxicity included hepatic toxicity in four patients and infection in two. Hematologic toxicity was observed as grade 3 anemia in three patients, grade 3 leukopenia in two patients, grade 3/4 neutropenia in two patients, and grade 3/4 thrombocytopenia in six patients. CONCLUSION: The present schedule of gemcitabine displays modest efficacy and mild toxicity in pretreated aggressive NHL.

Adult↗

Multicenter phase II study of fludarabine phosphate for patients with newly diagnosed lymphoplasmacytoid lymphoma, Waldenström's macroglobulinemia, and mantle-cell lymphoma.

PURPOSE: Fludarabine phosphate (F-AMP) has significant activity in follicular lymphoma and in B-cell chronic lymphatic leukemia, where it has demonstrated high complete response (CR) rates. Lymphoplasmacytoid (LPC) lymphoma, Waldenstrom's macroglobulinemia (WM), and mantle-cell lymphoma (MCL) also present with advanced-stage disease and are incurable with standard alkylator-based chemotherapy. A phase II trial was undertaken to determine the activity of F-AMP in patients newly diagnosed with these diseases. PATIENTS AND METHODS: Between 1992 and 1996, 78 patients (aged 18 to 75 years) received intravenous F-AMP (25 mg/m2/d for 5 days, every 4 weeks) until maximum response, plus two further cycles as consolidation. The primary end point was response rate; secondary end points included time to progression (TTP), duration of response, and overall survival (OS). RESULTS: Forty-four (62%) of 71 assessable patients had a response to F-AMP (LPC lymphoma, 63%; WM, 79%; MCL, 41%); the CR rate was 15%. At a median follow-up of 1.5 years, 19 of 44 responding patients have had progression of lymphoma; the median duration of response was 2.5 years. The median survival has not yet been reached. There was no significant difference in the duration of response or OS between patients with different histologies; TTP was shorter in patients with MCL (P = .015). Myelosuppression was relatively common, and the treatment-related mortality (TRM) was 5%, mostly associated with pancytopenia and infection. CONCLUSION: Single-agent fludarabine phosphate is active in previously untreated LPC lymphoma and WM, with only moderate activity in MCL. However, the CR rate is low, and the TRM is relatively high. Its role in combination chemotherapy remains to be demonstrated.

Adult↗

Report of an international workshop to standardize response criteria for non-Hodgkin's lymphomas. NCI Sponsored International Working Group.

Standardized guidelines for response assessment are needed to ensure comparability among clinical trials in non-Hodgkin's lymphomas (NHL). To achieve this, two meetings were convened among United States and international lymphoma experts representing medical hematology/oncology, radiology, radiation oncology, and pathology to review currently used response definitions and to develop a uniform set of criteria for assessing response in clinical trials. The criteria that were developed include anatomic definitions of response, with normal lymph node size after treatment of 1.5 cm in the longest transverse diameter by computer-assisted tomography scan. A designation of complete response/unconfirmed was adopted to include patients with a greater than 75% reduction in tumor size after therapy but with a residual mass, to include patients-especially those with large-cell NHL-who may not have residual disease. Single-photon emission computed tomography gallium scans are encouraged as a valuable adjunct to assessment of patients with large-cell NHL, but such scans require appropriate expertise. Flow cytometric, cytogenetic, and molecular studies are not currently included in response definitions. Response rates may be the most important objective in phase II trials where the activity of a new agent is important and may provide support for approval by regulatory agencies. However, the goals of most phase III trials are to identify therapies that will prolong the progression-free survival, if not the overall survival, of the treated patients. We hope that these guidelines will serve to improve communication among investigators and comparability among clinical trials until clinically relevant laboratory and imaging studies are identified and become more widely available.

Clinical Trials as Topic↗

Oxaliplatin pharmacokinetics during a four-hour infusion.

A new platin compound, oxaliplatin, has significant activity in advanced colorectal carcinomas. However, its pharmacokinetics have not been characterized adequately yet. This study extensively analyzes the pharmacokinetics of both ultrafiltrable (free) and protein-bound platin in 13 patients receiving 130 mg/m2 oxaliplatin as a 4-h infusion in combination with 375 mg/m2 5-fluorouracil as a 24-h infusion for advanced colorectal carcinomas. The interpatient variability was very low for all parameters analyzed. The levels of free platin decreased triphasically, with a mean terminal half-life of 27.3+/-10.6 h. The area under the time-concentration curve was 20.17+/-6.97 microg.h/ml and the total and renal clearances amounted to 222+/-65 and 121+/-56 ml/min, respectively. The values for the volume of distribution and for the maximum concentration at the end of infusion were 349+/-132 liters and 1612+/-553 ng/ml, respectively. On the basis of the simulation of the plasma levels and the urinary excretion of platin following the long-term administration of oxaliplatin as a constant-rate and a chronomodulated infusion, additional analyses are warranted to fully characterize the pharmacokinetics of the drug in these settings.

Adult↗

Leukaemia-associated immunophenotypes (LAIP) are observed in 90% of adult and childhood acute lymphoblastic leukaemia: detection in remission marrow predicts outcome.

Analysis of differentiation antigens on leukaemic blasts is routinely done for diagnostic purposes, i.e. determination of stage of differentiation and lineage assignment. Acute lymphoblastic leukaemias are also frequently characterized by a leukaemia-associated immunophenotype (LAIP), either the coexpression of differentiation antigens physiologically restricted to other stages of differentiation (asynchronous LAIP) or cell lineages (aberrant LAIP). We defined LAIP in 241 consecutive unselected B-lineage (n = 193) and T-lineage (n = 48) ALL by three-colour flow cytometry using directly conjugated monoclonal antibodies. The incidence of LAIP was found to be 91.7%. In 63% of patients two to six leukaemia-associated expression patterns were detected. In order to study the specificity of LAIP in a therapy-relevant setting, remission bone marrow samples from patients with B-lineage ALL were analysed for the expression of T-lineage-associated phenotypes on the normal bone marrow cells and vice versa. The frequency of all T-lineage LAIP+ cells and all aberrant B-lineage LAIP+ cells was <1% in regenerating bone marrow samples at different timepoints. The incidence and clinical significance of LAIP+ cells was studied in 196 remission marrows of 70 ALL patients (55 remaining in CCR, 14 with bone marrow relapse, one with isolated CNS relapse). The presence of >1% LAIP+ at two consecutive timepoints predicted 5/8 bone marrow relapses in B-lineage ALL. The occurrence of LAIP+ cells >1% in T-lineage ALL after induction therapy predicted relapse in 7/7 cases. In conclusion, flow cytometric detection of LAIP+ cells appears to be a powerful tool for the prediction of outcome in ALL.

Adolescent↗

Leukaemic blasts differ from normal bone marrow mononuclear cells and CD34+ haemopoietic stem cells in their metabolism of cytosine arabinoside.

Different metabolites of cytosine arabinoside (AraC) contribute to its cytotoxicity including incorporation of AraCTP into DNA, the incorporation of AraUMP into RNA, inhibition of polymerase alpha and beta (AraCMP/CTP), an impairment of repair mechanisms (AraCTP), alterations of phospholipid metabolism (AraCDP-choline), a direct membrane interaction (AraC), the alteration of signal transduction pathways (AraCDP-choline, AraCTP) and the induction of apoptosis. Since little is known about the potential differences in AraC metabolism between leukaemic blasts and normal haemopoietic progenitor cells, the formation of all known AraC metabolites was determined in bone marrow samples from patients with acute myeloid leukaemia (AML), healthy volunteers and specimens of cellsorted CD34+ haemopoietic stem cells. Highly significant differences were found for phosphorylated AraC metabolites (AraCMP, -CDP, -CTP, AraUMP) between AML and normal mononuclear bone marrow (ng/107 cells respectively 1.30 v 2.66; 2.65 v 7.50; 33.68 v 99.0; 1.18 v 5.70). The highest differences were found for formation of AraCDP-choline (3.75 v 12.86) which might be relevant for the high efficacy of high-dose AraC regimens. In contrast, no differences were found in the deamination product AraU (2.01 v 2.91). Only minute amounts of phosphorylated AraU derivatives were detected, providing an explanation for the lacking contribution of AraU to cytosine arabinoside cytotoxicity. Results in normal CD34+ haemopoietic stem cells did not differ significantly from normal bone marrow mononuclear cells and therefore justify their use as a surrogate in determining AraC-induced haematotoxicity. These data suggest a metabolic basis for the relative selectivity of AraC cytotoxicity for AML blasts and provide a means to determine the role of different metabolites and their related mechanism of action for overall AraC cytotoxicity.

Acute Disease↗

Radioimmunotherapy of small volume disease of colorectal cancer metastatic to the liver: preclinical evaluation in comparison to standard chemotherapy and initial results of a phase I clinical study.

At the time of surgery, occult metastases (micrometastases) are present in more than 50% of colorectal cancer patients, and the liver is the most frequent site of apparent metastatic disease. Frequently, adjuvant chemotherapy is unable to prevent tumor recurrence. Thus, novel therapeutic strategies are warranted. The aim of this study was to establish a model of human colon cancer metastatic to the liver of nude mice, to assess, in this setting, the therapeutic efficacy of radioimmunotherapy (RAIT) compared to standard chemotherapy and to evaluate, in a Phase I/II trial, the toxicity and therapeutic efficacy of RAIT in colorectal cancer patients with small volume disease metastatic to the liver. Multiple liver metastases of the human colon cancer cell line GW-39 were induced by intrasplenic injection of a 10% tumor cell suspension. Whereas controls were left untreated, therapy was initiated on day 10 or 20 after tumor inoculation with the 131I-labeled, low affinity anticarcinoembryonic antigen (anti-CEA) monoclonal antibody (MAb), F023C5 (Ka = 10(7) liters/mol), or the high-affinity anti-CEA MAb, MN-14 (Ka = 10(9) liters/mol), or chemotherapy (5-fluorouracil/leucovorin (folinic acid) versus irinotecan) at their respective maximum tolerated doses (MTDs). Twelve colorectal cancer patients with small volume disease metastatic to the liver (all lesions < or = 2.5 cm) were entered into a mCi/m2-based Phase I dose escalation study with 131I-labeled humanized version of MN-14, hMN-14. The patients were given single injections, starting at 50 mCi/m2 and escalating in 10-mCi/m2 increments. The MTD was defined as the dose level at which < or = 1 of 6 patients develop grade 4 myelotoxicity. In the mice, untreated controls died from rapidly progressing hepatic metastases at 6-8 weeks after tumor inoculation. The life span of mice treated with 5-fluorouracil/leucovorin was prolonged for only 1-3 weeks, whereas irinotecan led to a 5-8-week prolongation. In contrast, at their respective MTDs, the 131I-labeled low-affinity anti-CEA MAb, F023C5, led to a 20% permanent cure rate, and the high affinity MAb, MN-14, led to an 80% permanent cure rate, when therapy was initiated at 10 days after tumor inoculation. In the 20-day-old tumor stage, although it prolonged life, 131I-F023C5 was unable to achieve cures, whereas 131I-MN-14 was still successful in 20%. Histologically, no remaining viable tumor cells could be demonstrated in these animals surviving > 6 months. In patients, the MTD was reached at 60 mCi/m2 of hMN-14 (at 70 mCi/m2, two of three grade 4 myelotoxicities). Of 11 assessable patients, 2 had partial remissions (corresponding to an objective response rate of 18%), and 5 (45%) had minor/mixed responses or experienced stabilization of previously rapidly progressing disease. These data suggest that in small volume disease, RAIT may be superior to conventional chemotherapy. Antibodies of higher affinity seem to be clearly superior. The clinical response rates in patients with small volume disease are encouraging, being comparable to the response rates of conventional chemotherapeutic regimens but with fewer side effects. Ongoing studies will show whether treatment at the MTD will further improve therapeutic results.

Adult↗

Low- versus high-dose radioimmunotherapy with humanized anti-CD22 or chimeric anti-CD20 antibodies in a broad spectrum of B cell-associated malignancies.

Both CD22 and CD20 have been used successfully as target molecules for radioimmunotherapy (RAIT) of low-grade B cell non-Hodgkin's lymphoma. Because both CD20 and CD22 are highly expressed relatively early in the course of B cell maturation, and because its expression is maintained up to relatively mature stages, we studied the potential of the humanized anti-CD22 antibody, hLL2, as well as of the chimeric anti-CD20 (chCD20) antibody, rituximab (IDEC-C2B8), for low- or high-dose (myeloablative) RAIT of a broad range of B cell-associated hematological malignancies. A total of 10 patients with chemorefractory malignant neoplasms of B cell origin were studied with diagnostic (n = 5) and/or potentially therapeutic doses (n = 9) of hLL2 (n = 4; 0.5 mg/kg, 8-315 mCi of 131I) or chCD20 (n = 5; 2.5 mg/kg, 15-495 mCi of 131I). The diagnostic doses were given to establish the patients' eligibility for RAIT and to estimate the individual radiation dosimetry. One patient suffered of Waldenström's macroglobulinemia, eight patients had low- (n = 4), intermediate- (n = 2) or high- (n = 2) grade non-Hodgkin's lymphoma, and one patient had a chemorefractory acute lymphatic leukemia, after having failed five heterologous bone marrow or stem cell transplantations. Three of these 10 patients were scheduled for treatment with conventional (30-63 mCi, cumulated doses of up to 90 mCi of 131I) and 7 with potentially myeloablative (225-495 mCi of 131I) activities of 131I-labeled hLL2 or chCD20 (0.5 and 2.5 mg/kg, respectively); homologous (n = 6) or heterologous (n = 1) stem cell support was provided in these cases. Good tumor targeting was observed in all diagnostic as well as posttherapeutic scans of all patients. In myeloablative therapies, the therapeutic activities were calculated based on the diagnostic radiation dosimetry, aiming at lung and kidney doses < or = 20 Gy. Stem cells were reinfused when the whole-body activity retention fell below 20 mCi. In eight assessable patients, five had complete remissions, two experienced partial remissions (corresponding to an overall response rate of 87%), and one (low-dose) patient had progressive disease despite therapy. In the five assessable, actually stem-cell grafted patients, the complete response rate was 100%. Both CD20 and CD22 seem to be suitable target molecules for high-dose RAIT in a broad spectrum of hematological malignancies of B cell origin with a broad range of maturation stages (from acute lymphatic leukemia to Waldenström's macroglobulinemia). The better therapeutic outcome of patients undergoing high-dose, myeloablative RAIT favors this treatment concept over conventional, low-dose regimens.

Adolescent↗

Induction of inducible nitric oxide synthase is an essential part of tumor necrosis factor-alpha-induced apoptosis in MCF-7 and other epithelial tumor cells.

TNF-alpha-induced cytotoxicity is mediated by the intracellular "death domain" of the 55-kDa TNF-alpha receptor and has been demonstrated to be coupled with induction of inducible nitric oxide synthase (iNOS), leading to generation of nitric oxide radicals (NO*). Because it is still widely unknown, to what extent NO* participates in the execution of TNF-alpha-induced apoptosis, NO* production, iNOS expression, and enzyme activity in relation to TNF-alpha-induced apoptotic cell death were investigated in the human breast cancer cell line MCF-7 and various other malignant cell lines. Incubation with TNF-alpha led to induction of iNOS mRNA and protein as well as enhancement of NOS activity. Augmented synthesis of NO2, the stable end product of NO* generation, was significantly correlated with augmented rates of cell death. Measurement of TNF-alpha-triggered production of reactive oxygen species (ROS) suggested a major role for NO* within the generated oxygen radicals. Dying cells showed characteristic features of apoptosis. Addition of cycloheximide (CX) enhanced apoptotic cell death by increasing iNOS activity. L-Nitro-arginine-methylester (L-NAME), a competitive NOS-inhibitor, and iNOS antisense oligonucleotides effectively prevented NO2 generation and apoptosis. Evaluation of iNOS expression during TNF-alpha-induced cell death in various malignant cell lines demonstrated iNOS positivity for all TNF-alpha-sensitive cells. The only primarily resistant line was iNOS negative. In a resistant variant of MCF-7, iNOS mRNA was still detectable; however, treatment with TNF-alpha did not enhance NOS activity. TNF-alpha sensitivity and NO2 production were completely restored by the addition of CX. Taken together, iNOS induction plays an essential role in TNF-alpha-induced apoptosis of the investigated cell lines. Further studies are necessary to define the impact of NO* in relation to other specific effectors of apoptosis such as the caspases.

Apoptosis↗

Partial tandem duplications of the MLL gene are detectable in peripheral blood and bone marrow of nearly all healthy donors.

Partial tandem duplication within the MLL gene has recently been described as a novel genetic alteration in acute myeloid leukemia (AML). It has been associated with trisomy of chromosome 11, but was also identified in AML patients with normal karyotypes. The current study was performed to investigate whether MLL duplications are restricted to AML, and hence whether they may also occur in normal hematopoietic cells. MLL-duplication transcripts were analyzed by nested reverse-transcriptase polymerase chain reaction (RT-PCR) in peripheral blood in two groups of 45 and 20 patients, respectively, as well as in two bone marrow samples from healthy volunteers. Duplications were detected in two independent nested RT-PCR experiments in the peripheral blood samples of 38 of 45 (84%) and 20 of 20 (100%) of the two groups and in both bone marrow samples. On this basis, MLL duplications seem to occur frequently in a subset of cells in normal hematopoiesis. The type of partially duplicated MLL transcripts varied substantially. Three transcripts were identical to those known from AML. In addition, four new transcripts were characterized. Three of these four were in frame and potentially translatable. MLL duplications were also detected by seminested genomic PCR with intron 9- and intron 1-specific primers in 20 of 20 peripheral blood samples studied, indicating that the duplications are genomically fixed at the DNA level and are not an RT-PCR artifact. In summary, MLL duplications are regularly generated by homologous ALU recombination in a small number of hematopoietic cells of most or even all healthy donors. These data suggest that MLL duplications are not implicated in the malignant transformation in AML, or alternatively, that only a few cells will acquire additional oncogenic mutations necessary to establish the malignant phenotype of AML.

Adolescent↗

Elevated serum level of soluble CD23 precedes development of B-non-Hodgkin's lymphoma in SIV-infected Rhesus monkeys.

Patients with HIV infection are at high risk for the development of high-grade B-non-Hodgkin's lymphoma (B-NHL). The aim of this study was identification of a predictive diagnostic marker for HIV-associated B-cell lymphomas, using simian-immunodeficiency-virus (SIV)-infected Rhesus monkeys as a well-established in vivo model of HIV-associated lymphomagenesis. We infected 26 monkeys (Macaca mulatta) with SIVmax and measured serum levels of sCD23 longitudinally until necropsy. Of the 26 monkeys, 9 developed high-grade B-NHL, which was preceded by lymphadenopathy (NHL+/LA+) (group 1). Among the 17 animals that remained without clinical evidence of lymphoma during the observation period, 8 developed LA (group 2) and 9 were NHL- and LA-negative (NHL-/LA-) (group 3). Elevation of sCD23 serum levels preceded B-cell lymphoma development, with a median of 44 U/ml in group 1 vs. 7 U/ml and 8 U/ml in groups 2 and 3 respectively, 32 weeks after infection. Differences in the serum level of sCD23 between group 1 vs. groups 2 and 3 became statistically significant 32 to 56 weeks after infection. At necropsy, serum levels of sCD23 were significantly higher in group 1 than in group 2 or group 3; 6/6 samples of SIV-associated B-NHL were positive for gene transcription of CD23 and its receptor CD21 as assessed by RT-PCR. The data point to a potential role of sCD23 as a predictive marker for the development of HIV-associated B-NHL. Moreover, the in vivo model of SIV-infected monkeys suggests the possibility of exactly analyzing the pathobiological role of sCD23 in the lymphomagenesis of SIV-associated B-NHL.

Animals↗

Failure of fluconazole prophylaxis to reduce mortality or the requirement of systemic amphotericin B therapy during treatment for refractory acute myeloid leukemia: results of a prospective randomized phase III study. German AML Cooperative Group.

BACKGROUND: Invasive fungal infections have increasingly become a matter of concern with regard to patients receiving intensive myelosuppressive therapy for hematologic malignancies. Such infections, especially prolonged neutropenia systemic fungal infections, may contribute substantially to infectious complications and early death. Measures for early detection and effective prophylactic strategies using active and nontoxic antifungal agents are therefore urgently needed. METHODS: The current randomized study was initiated to assess the efficacy of oral fluconazole as systemic antifungal prophylaxis for high risk patients with recurrent acute myeloid leukemia undergoing intensive salvage therapy. RESULTS: Of 68 fully evaluable patients, 36 were randomized to fluconazole in addition to standard prophylaxis with oral co-trimoxazol, colistin sulphate, and amphotericin B suspension, and 32 were randomized to standard prophylaxis only. No major differences between the two groups were observed in the number of episodes of fever of unknown origin (61% vs. 50%) or clinically defined infections (56% vs. 50%). Microbiologically defined infections were more frequent in the fluconazole group (50% vs. 31%), mainly due to a higher incidence of bacteremias (42% vs. 22%). There were two cases of proven invasive fungal infections in each group. Systemic amphotericin B was administered more frequently to patients receiving fluconazole prophylaxis (56% vs. 28%). Fluconazole prophylaxis had no impact on the rate of early death or overall survival. CONCLUSIONS: For patients with high risk recurrent acute myeloid leukemia undergoing intensive salvage therapy, antifungal prophylaxis with fluconazole was not superior to standard prophylaxis only.

Acute Disease↗

MLL and CALM are fused to AF10 in morphologically distinct subsets of acute leukemia with translocation t(10;11): both rearrangements are associated with a poor prognosis.

The translocation t(10;11)(p13;q14) has been observed in acute lymphoblastic leukemia (ALL) as well as acute myeloid leukemia (AML). A recent study showed a MLL/AF10 fusion in all cases of AML with t(10;11) and various breakpoints on chromosome 11 ranging from q13 to q23. We recently cloned CALM (Clathrin Assembly Lymphoid Myeloid leukemia gene), the fusion partner of AF10 at 11q14 in the monocytic cell line U937. To further define the role of these genes in acute leukemias, 10 cases (9 AML and 1 ALL) with cytogenetically proven t(10;11)(p12-14;q13-21) and well-characterized morphology, immunophenotype, and clinical course were analyzed. Interphase fluorescence in situ hybridization (FISH) was performed with 2 YACs flanking the CALM region, a YAC contig of the MLL region, and a YAC spanning the AF10 breakpoint. Rearrangement of at least one of these genes was detected in all cases with balanced t(10;11). In 4 cases, including 3 AML with immature morphology (1 AML-M0 and 2 AML-M1) and 1 ALL, the signals of the CALM YACS were separated in interphase cells, indicating a translocation breakpoint within the CALM region. MLL was rearranged in 3 AML with myelomonocytic differentiation (2 AML-M2 and 1 AML-M5), including 1 secondary AML. In all 3 cases, a characteristic immunophenotype was identified (CD4+, CD13-, CD33+, CD65s+). AF-10 was involved in 5 of 6 evaluable cases, including 1 case without detectable CALM or MLL rearrangement. In 2 complex translocations, none of the three genes was rearranged. All cases had a remarkably poor prognosis, with a mean survival of 9.6 +/- 6.6 months. For the 7 AML cases that were uniformly treated according to the AMLCG86/92 protocols, disease-free and overall survival was significantly worse than for the overall study group (P = .03 and P = .01, respectively). We conclude that the t(10;11)(p13;q14) indicates CALM and MLL rearrangements in morphologically distinct subsets of acute leukemia and may be associated with a poor prognosis.

Acute Disease↗

[Systemic therapy of low malignancy non-Hodgkin lymphomas].

Substantial progress has been achieved in eludicating the molecular mechanisms of malignant transformation, in establishing therapeutic standards and in evaluating innovative treatment strategies in patients with low grade Non-Hodgkin's Lymphoma. Correlation of genetic aberrations and immunologic marker profiles to histopathological entities and the clinical course has lead to a new transatlantic lymphoma classification. Today, application of 6-8 courses of moderately intensive induction polychemotherapy induces partial or complete remissions in 80% of patients in stage III or IV. Longterm maintenance therapy with interferon alpha significantly prolongs progression free survival. Current multicenter trials evaluate the curative potential of high-dose chemotherapy with autologous stem cell transplantation. Recently, several new approaches including new cytostatic drugs, immunotherapy with monoclonal antibodies and gene therapy with antisense oligonucleotides have been developed and have achieved remissions in pretreated patients. In the future, intensification of chemotherapy and the new treatment options may offer the potential for cure in patients with low malignant Non-Hodgkins Lymphoma.

Antineoplastic Combined Chemotherapy Protocols↗

[Clinical studies in oncology. Relevance, design, ethical considerations].

BACKGROUND: Clinical research in oncology includes the evaluation of diagnostic, prognostic and therapeutic parameters in order to establish standards for the different tumor entities. Prerequisite is the retrospective and prospective analysis of large patient groups with established statistical methods. New potentially better strategies have to be compared in randomised studies with the respective "gold standard". The central role of clinical studies for evaluation and optimisation of therapy can be considered as moral obligation to included the maximal possible number of patients in clinical studies. However, only a small number of tumor patients in Germany is treated in controlled clinical studies. Reasons are lack of organisational structures, but also ethical considerations. STUDY DESIGNS: In this article several models for clinical studies are discussed with respect to their statistical significance, indication, and potential ethical objections. CONCLUSION: Aim of the discussion is to increase the acceptance of the necessity of clinical studies for evaluation and optimisation of therapeutic options in oncology.

Clinical Trials as Topic↗