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1.
Thirteen patients (7 male, 9 female) aged 22-71 years (means = 55 years) with acute non-lymphocytic leukemia and contraindications for anthracyclin therapy were treated with combined chemotherapy using m-amsacrine primarily or in relapse. The main reasons for avoiding cardiotoxic substances were overt cardiac insufficiency and former administration of daunorubicin with more than 540 mg/m2 body surface area. Amsacrine was combined with 6-thioguanine, VP 16-213 and cytosine arabinoside in conventional or high dosage. Eight out of 13 patients (62%) achieved complete remission after one or two courses of chemotherapy. One patient showed partial remission and could be brought into complete remission with another chemotherapy using high-dose ara-C and mitoxantrone. Three patients died in aplasia after chemotherapy and 1 other patient had to be regarded as a complete non-responder. Remission duration and survival time for the 8 successfully-treated patients so far is 1-12 months; however, medians have not yet been reached, since only one of the eight patients relapsed after 6 months of complete remission. These data indicate a high efficacy of m-amsacrine in combined chemotherapy for acute non-lymphocytic leukemia in high-risk patients with contraindications for anthracyclins.  相似文献   
2.
Differential pattern of DNA-aneuploidy in human malignancies   总被引:5,自引:0,他引:5  
The differential pattern of DNA-aneuploidy, detected by flow cytometry (FCM) regarding its frequency, grade and multiclonality, was investigated and correlated to tumor type, malignancy grade, tumor stage and prognosis in a multi-institutional study at the University of Münster. High resolution measurements using admixed normal blood reference cells were undertaken in 2413 cases of 13 different malignant diseases and in 776 benign lesions or samples. The incidence of DNA-aneuploidy was highest in melanomas, carcinomas, testicular tumors, sarcomas (75%-95%) and myelomas (65%). Acute leukemias showed an intermediate DNA-aneuploidy rate of 40% with special subgroups represented by common ALL (44%), p less than 0.05) and myelomonocytic/monocytic AML (47%, p less than 0.01). The lowest DNA-aneuploidy-rate was found in basal cell skin carcinomas (19%) and congenital melanocytic nevi (9%). No case of DNA-aneuploidy was observed in the 776 benign lesions or samples.--DNA-indices giving the grade of DNA-aneuploidy with 1.0 for normal diploid G1/0 cells were found distributed predominantly between 1.0 and 2.0 in the solid tumors, except testicular tumors, clustering around a triploid maximum at 1.5. DNA-indices of myelomas and acute leukemias generally ranged below 1.25 with lower DNA-aneuploidy grades in AML than in ALL (p less than 0.01).--In melanomas the aneuploidy rate was higher (86%) in metastases than in the primary tumors (54%, p = 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
3.
What's new in malignant tumors in acquired immunodeficiency disorders?   总被引:1,自引:0,他引:1  
An increased incidence of malignant tumors has long been recognized in patients with primary immune defects such as the X-linked lympho-proliferative syndrome or the Wiskott Aldrich syndrome and has recently become a major concern also in cases with acquired immunodeficiency. The latter may be induced by cytostatic therapy for cancer, extended immunosuppression following organ transplantation or HIV infection. The spectrum of secondary cancers is, however, different within these three groups of secondary immune defects with acute myeloid leukemia being the most common malignant disease after cytostatic therapy, with skin or lip cancer followed by non-Hodgkin's lymphoma as the prevalent malignancies after organ transplantations and Kaposi sarcoma and non-Hodgkin's lymphoma as the predominant cancers associated with HIV infection. The pathogenesis of Kaposi sarcoma and non-Hodgkin's lymphoma is possibly related to viral infections by cytomegalovirus and Epstein-Barr virus inducing an increased proliferation and possibly the coactivation of transforming genes of oncogenic potential. In AIDS patients Kaposi sarcoma is diagnosed in up to 40% of homosexual men while the other risk groups are less frequently involved. 4-10% of HIV infected patients experience non Hodgkin's lymphoma predominantly of B-cell type and intermediate or high grade malignancy with frequent extranodal manifestations. Other types of tumors occur at a substantially lower frequency and are not clearly related to the HIV infection. The overall survival of patients suffering from malignant tumors in the state of immunodeficiency is poor and the possibilities for therapeutic intervention are limited by the risk of accelerating the pre-existing suppression of defense mechanisms.  相似文献   
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Since cell kinetic bone marrow studies have so far exclusively been carried out on aspiration material and have yielded inconsistent or even contradictory results, we investigated the adequacy and reliability of aspirates for cell kinetic analyses in comparison to biopsies. Paired samples of bone marrow (133) were taken simultaneously by aspiration and Jamshidi biopsy from 48 patients with acute leukemias and 67 patients with non-leukemic disorders. Cell kinetic analysis by (1) flow cytometry (FCM) of cellular DNA and RNA content, (2) autoradiography for [3H]TdR pulse labelling indices and (3) liquid scintillation counting of [3H]TdR uptake revealed significantly higher values in biopsies (p less than 0.001) exceeding the corresponding results from aspirates on average by factors of 1.65 for FCM S-phase index, 1.90 for G0/1 cells with high RNA content, 1.82 for [3H]TdR LI and 1.90 for [3H]TdR uptake. In more than 70% of all samples results from biopsies were 1.1-11.4 times higher, indicating that aspirates were equivalent to biopsies in fewer tan 30% of cases. Cell kinetic analysis in vitro blood/biopsy mixtures and measurements of DNA synthesis rate in corresponding aspirates and biopsies revealed that these discrepancies are due to the contamination of aspirates with non-proliferating nucleated blood cells. Biopsy, however, was found to provide representative and reproducible sampling of marrow for cell kinetic studies and should replace the presently used aspirate already characterized as "unreliable marrow juice" by Dameshek et al. in 1937 [18].  相似文献   
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7.
The aim of this study was to compare the pattern of karyotype abnormalities of therapy-related acute myeloid leukemia (t-AML) (n=93) with de novo AML (n=1091), and to evaluate their impact on prognosis. Favorable, intermediate, and unfavorable cytogenetics were observed in 25.8, 28.0, and 46.2% of t-AML, and in 22.2, 57.3, and 20.4% of de novo AML. The median overall survival (OS) was shorter in t-AML than in de novo AML (10 vs 15 months, P=0.0007). Favorable and unfavorable cytogenetics had a prognostic impact with respect to OS in both t-AML (P=0.001 and 0.0001) and de novo AML (P<0.0001 and <0.0001). To define the overall prognostic impact of cytogenetics and t-AML, a multivariate Cox's regression analysis was performed for OS with favorable cytogenetics, unfavorable cytogenetics, t-AML, age, and white blood cell (WBC) count as covariates. All parameters proved to be independently related to OS (P=0.001 for t-AML, P<0.0001 for all other parameters). Within patients with t-AML, there were significant correlations between OS and both unfavorable (P<0.0001) and favorable cytogenetics (P=0.001), while age and WBC count had no impact on OS. In conclusion, these data indicate that cytogenetics are an important prognostic parameter in t-AML. Furthermore, t-AML is an unfavorable factor independent of cytogenetics with respect to survival.  相似文献   
8.
PURPOSE: On the basis of cytomorphology according to the French-American-British (FAB) classification, we evaluated the prognostic impact of dysplastic features and other parameters in de novo acute myeloid leukemia (AML). We also assessed the clinical significance of the recently introduced World Health Organization (WHO) classification for AML, which proposed dysplasia as a new parameter for classification. PATIENTS AND METHODS: We analyzed prospectively 614 patients with de novo AML, all of whom were diagnosed by central morphologic analysis and treated within the German AML Cooperative Group (AMLCG)-92 or the AMLCG-acute promyalocytic leukemia study. RESULTS: Patients with AML M3, M3v, or M4eo demonstrated a better outcome compared with all other FAB subtypes (P <.001); no prognostic difference was observed among other FAB subtypes. The presence or absence of dysplasia failed to demonstrate prognostic relevance. Other prognostic markers, such as age, cytogenetics, presence of Auer rods, and lactate dehydrogenase (LDH) level at diagnosis, all showed significant impact on overall and event-free survival in univariate analyses (P <.001 for all parameters tested). However, in a multivariate analysis, only cytogenetics (unfavorable or favorable), age, and high LDH maintained their prognostic impact. Dysplasia was not found to be an independent prognostic parameter, but the detection of trilineage dysplasia correlated with unfavorable cytogenetics. CONCLUSION: Our results indicate that cytomorphology and classification according to FAB criteria are still necessary for the diagnosis of AML but have no relevance for prognosis in addition to cytogenetics. Our results suggest that the WHO classification should be further developed by using cytogenetics as the main determinant of biology. Dysplastic features, in particular, have no additional impact on predicting prognosis when cytogenetics are taken into account.  相似文献   
9.
Purpose: To evaluate the effect of biochemical modulation by PALA and methotrexate on the therapeutic activity of 5-fluorouracil (5-FU) in patients with advanced pancreatic adenocarcinoma.Patients and methods: The treatment protocol consisted of phosphonacetyl-L-aspartate (PALA) 250 mg/m2 i.v. 15-minute infusion followed by methotrexate 200 mg/m2 i.v. 30-minute infusion on day 1 and 5-FU 600 mg/m2 i.v. push on day 2. Folinic acid was given at 15 mg/m2 p.o. every six hours for eight doses, starting 24 hours after methotrexate infusion. Cycles were repeated every two weeks.Results: Thirty patients with advanced chemotherapy-naive pancreatic cancer were included; 26 had measurable disease. Median age 56 years (27–72); median PS 1 (0–2). One PR (3.9%) was achieved; nine patients had stable disease. Median time to progression was 91 days. Median survival was 177 days and one year survival was 13.3% (4 of 30 patients). Treatment was well tolerated; diarrhea WHO grade 2 or 3 occurred in six patients; stomatitis WHO grade 2 and 3 in nine patients.Conclusions: Modulation of 5-FU by PALA and MTX given in this dose and schedule appears to be ineffective in patients with advanced pancreatic adenocarcinoma.  相似文献   
10.
We performed microarray analyses in AML with trisomies 8 (n=12), 11 (n=7), 13 (n=7), monosomy 7 (n=9), and deletion 5q (n=7) as sole changes to investigate whether genomic gains and losses translate into altered expression levels of genes located in the affected chromosomal regions. Controls were 104 AML with normal karyotype. In subgroups with trisomy, the median expression of genes located on gained chromosomes was higher, while in AML with monosomy 7 and deletion 5q the median expression of genes located in deleted regions was lower. The 50 most differentially expressed genes, as compared to all other subtypes, were equally distributed over the genome in AML subgroups with trisomies. In contrast, 30 and 86% of the most differentially expressed genes characteristic for AML with 5q deletion and monosomy 7 are located on chromosomes 5 or 7. In conclusion, gain of whole chromosomes leads to overexpression of genes located on the respective chromosomes. Losses of larger regions of the genome translate into lower expression of the majority of genes represented by only one allele. The reduced expression of these genes is the most characteristic difference in gene expression profiles between AML with monosomy 7 and AML with deletion 5q, respectively, and other AML subtypes. Therefore, these data provide evidence that gene dosage effects gene expression in AML with unbalanced karyotype abnormalities. Losses of specific regions of the genome determine the gene expression profile more strongly than the gain of whole chromosomes.  相似文献   
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