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T Büchner

Publications and source records attributed to T Büchner.

At least 163 records · Page 9Linked to original sources
PubMed1987

High-dose cytosine arabinoside and mitoxantrone: a highly effective regimen in refractory acute myeloid leukemia.

In a clinical phase I/II study, high-dose cytosine arabinoside and mitoxantrone (HAM) were given in combination to 40 patients with refractory acute myeloid leukemia. All patients had received a 9-day combination of thioguanine, Ara-C, and daunorubicin (TAD-9) as standardized first-line treatment. Refractoriness was defined as (a) nonresponse against two TAD-9 induction cycles, (b) early relapse within the first 6 months on monthly maintenance or after TAD-9 consolidation, (c) relapse after 6 months with nonresponse against one additional TAD-9 cycle, and (d) second and subsequent relapses after successful TAD-9 therapy at the preceding relapse. Therapy consisted of HD-Ara-C 3 g/m2 every 12 hours on days 1 through 4; mitoxantrone was started at 12 mg/m2/day on days 3, 4, and 5 and was escalated to 4 and 5 doses of 10 mg/m2/day on days 2 through 5 and 2 through 6. Of the 40 patients, 21 achieved a complete remission (53%), 1 patient had a partial remission, and 5 patients were nonresponders. Thirteen patients died in aplasia due to infections (n = 11), pericardiac effusion, or acute cardiomyopathy. Nonhematologic side effects consisted predominantly of nausea and vomiting, mucositis, and diarrhea. Central nervous system (CNS) symptoms were observed during six treatment courses. Recovery of blood counts occurred at a median of 27 days from the onset of treatment; the median time to complete remission was 36 days. Two of the 21 responders underwent successful bone marrow transplantations. The median remission duration for the remaining 19 patients is 4.5 months, and the median survival time is 9 months. These data emphasize that HAM has high antileukemic activity in refractory AML and strongly suggest starting the combination at earlier stages in AML therapy.

Adolescent↗
PubMed1987

High-dose cytosine arabinoside in combination with mitoxantrone for the treatment of refractory acute myeloid and lymphoblastic leukemia.

In the present study 55 patients with refractory acute myeloid leukemia (AML) (n = 44) and acute lymphoblastic leukemia (ALL) (n = 11) were treated with high-dose cytosine arabinoside (HD-ara-C) and mitoxantrone (HAM) to assess the toxicity and antileukemic activity of the two-drug combination. All patients had received a standardized first-line therapy according to the corresponding multicenter trials of the German AML and ALL cooperative groups and were considered refractory to conventional treatment. Therapy consisted of HD-ara-C 3 g/m2 every 12 hours on days 1 to 4; mitoxantrone was started at 12 mg/m2/d on days 3, 4, and 5 and was escalated to four and five doses of 10 mg/m2/d on days 2 to 5 and 2 to 6. From the 44 patients with AML, 24 (54%) achieved a complete remission, two a partial remission, and five were nonresponders. Thirteen patients died of infections (n = 11), pericardiac effusion, or acute cardiomyopathy. In refractory ALL, seven of 11 patients (64%) went into a complete remission, one patient was resistant, and three patients were early deaths. Nonhematologic side effects consisted predominantly of nausea and vomiting, mucositis, and diarrhea. More severe CNS symptoms were encountered during five treatment courses. The median time to complete remission was 36 days. Excluding five patients who underwent bone marrow transplantations, the median remission duration was 4.5 months in AML and 2.3 months in ALL. The median survival time was three months for all patients and nine months for responders only. These data emphasize a high antileukemic activity of HAM in refractory AML and ALL and support the incorporation of the HAM regimen into first-line treatment.

Adolescent↗
PubMed1986

DNA stemline heterogeneity in colorectal cancer.

The current study was carried out on 88 colorectal carcinomas to assess the degree of intratumor heterogeneity as reflected by multiple aneuploid DNA stemlines and their relation to tumor stage and morphologic differentiation. Each tumor was segregated into an average of nine specimens (3-15), which were analyzed separately. DNA aneuploidies were identified in 72 cases (82%), 29 revealing multiple aneuploid DNA stemlines with up to four aneuploid subpopulations. In 10 of the 29 carcinomas with DNA stemline heterogeneity, a ratio of 2:1 was calculated from the different DNA indices, possibly indicating that the additional DNA stemline emerged from the first one by doubling its DNA content. No correlation was found between the overall frequency of DNA aneuploidies or heterogeneous DNA stemlines and the tumor stage according to Dukes' staging. Well-differentiated carcinomas tended to express aneuploid DNA stemlines more frequently than moderately or poorly differentiated tumors, although the morphologic intratumor heterogeneity did not correspond to the appearance of multiple aneuploid DNA stemlines. These data indicate a high degree of intraneoplastic diversity in colorectal cancer and emphasize the usefulness of DNA analyses for the quantitative assessment of tumor heterogeneity.

Aneuploidy↗
PubMed1986

DNA aneuploidies in adult patients with acute myeloid leukemia. Incidence and relation to patient characteristics and morphologic subtypes.

Analyses of the cellular DNA content were carried out by flow cytometry (FCM) in 148 adult patients with acute myeloid leukemia (AML) to assess the incidence of DNA aneuploidies and its relation to patient characteristics and morphologic subtypes. DNA aneuploidies were found in 54 of 131 patients with de novo AML (41.2%) and in 4 of 17 patients with AML after preleukemic syndromes. Subclassification according to morphology revealed the lowest rate of DNA aneuploidies in M1 leukemias (25%) and a significantly lower degree of DNA aneuploidy in M1 and M2 cases as compared to M4 and M5 subtypes (P less than 0.05). Within the group of M4 and M5 leukemias, patients less than or equal to 40 years of age had a higher frequency of aneuploid DNA stemlines (71.4%) than older patients (33.3%) (P less than 0.025). No differences between patients with and without DNA aneuploidy were identified for the initial leukocyte count, serum LDH, bone marrow S-phase index, bone marrow cell count/mm3 bone marrow nor the initial response to the induction regimen of 6-thioguanine, cytosine arabinoside, and daunorubicin (TAD). For remission duration a tendency towards a higher proportion of lung remissions was observed in patients with DNA aneuploidy.

Adolescent↗
PubMed1986

Frequency and clinical significance of DNA aneuploidy in acute leukemia.

Analyses of the cellular DNA content were carried out in 446 patients with newly diagnosed acute myeloid (AML) and lymphoblastic (ALL) leukemias in order to assess the frequency of DNA aneuploidies and its relation to immunologic and morphologic subtypes as well as its prognostic relevance. Based on high resolution FCM analyses and standardized reference measurements, DNA aneuploidies were identified at a similar frequency in children and adults with AML (38.0% and 40.0%) and ALL (40.0% and 37.4%). In AML aneuploid DNA stemlines were significantly less frequent in FAB-M 1 cases as compared to the other morphologic subtypes (p less than 0.05), whereas the degree of DNA aneuploidy was significantly lower in M 1 and M 2 leukemias as compared to the M 4 and M 5 subgroups (p less than 0.05). In ALL non-T/non-B and C-ALL revealed a higher frequency of DNA aneuploidies than T- and Null-ALL cases (p less than 0.05). No differences in the response to induction therapy were found between patients with and without DNA aneuploidy in children or adults with AML or ALL. In the childhood ALL trial BFM 79/81, however, a significantly higher frequency of long term remissions was observed in children with DNA aneuploidy (0.91 versus 0.66 at five years, p = 0.053). A similar though not significant tendency was also revealed from the AML studies BFM 78 in children and 78/81 in adults. In the subsequent studies these differences could not be confirmed at present, possibly because of the considerably shorter observation time.

Adult↗
PubMed1986

[Acute myeloid leukemia (AML) in adults. Further development of therapy based on clinical phase II and phase III studies].

By a review of relevant clinical studies on adult AML no substantial progress can be seen in the eighties so far. After the development of successful chemotherapy regimens during the seventies, further improvement can only be expected in small steps. Clinical studies, therefore, should concentrate on the analysis of the different components and new elements of treatment in order to utilize and combine them more effectively. For this purpose, a standardization of treatment and, for many aspects, a randomized comparison is inevitable. Thus, the role of monthly maintenance as well as of a special type of immunotherapy could be elucidated for the first time by our multicenter trial.

Adult↗
PubMed1986

High-dose cytosine-arabinoside and mitoxantrone in refractory acute myeloid leukemia: a clinical phase I/II-study.

In a multi-institutional study 26 patients with refractory acute myeloid leukemia were entered into a phase I/II study of HD-ara-C and mitox. HD-ara-C 3 g/m2 q 12h was given by 3h infusion on days 1-4. Mitox was started at 12 mg/m2/d on days 3, 4 and 5, and escalated to 4 and 5 doses of 10 mg/m2/d on days 2-5 and 2-6, respectively. From 24 patients presently evaluable for response, 12 achieved a CR and 2 a PR. 7 patients died of infectious complications within the first 4 weeks of treatment while persistent AML was found in 3 cases. Except for one death, possibly related to acute cardiomyopathy, toxicity was mild to moderate consisting of nausea and vomiting, mucositis and diarrhea. These data indicate a high anti-leukemic activity of HD-ara-C/mitox in AML refractory against conventional chemotherapy.

Anthraquinones↗
PubMed1985

Differential pattern of DNA-aneuploidy in human malignancies.

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)

Adult↗
PubMed1985

Immunotherapy with allogeneic neuraminidase-treated blasts for maintenance in acute myelogenous leukemia (AML). Significant prolongation of remission duration in patients receiving at least 3 cycles of therapy.

102 patients with AML (leukemia after preleukemia, 2nd neoplasia included) were treated for remission induction by a modified TAD regimen in Munster; 55 patients (54%) achieved a complete remission (CR). For CR maintenance 40 patients were eligible for randomization according to the study protocol: cyclic chemotherapy (CT) alone vs. chemoimmunotherapy (CIT: plus allogeneic Neuraminidase-treated blasts in high dosage). 5 CR patients, induced identically in Essen, were randomized additionally. Evaluating all patients randomized there is only a marginally beneficial effect of CIT (21 patients) compared to CT (24 patients) concerning median survival (1020+ vs. 612 days) and relapse-free survival (494 vs. 380 days) until now. For patients receiving more than 2 cycles of maintenance therapy, however, CIT prolongs relapse-free survival significantly (930+ vs. 409 days; p = 0,02); that is also true for remission duration. This suggests that only repeated application of blasts may induce an immune response leading to a biologically relevant antileukemic effect.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1985

[AMSA/etoposide (VP 16-213). A phase I/II study in refractory acute myeloid leukemia].

In a phase I/II study the tolerable doses and antileukemic efficacy of the combination AMSA and etoposide (VP 16-213) was assessed in 20 patients with refractory acute myeloid leukemia. The following 5 day treatment course was found tolerable and effective: AMSA 210 mg/m2/die on days 2, 3 and 4, and etoposide on days 1 and 5 as a 1 h infusion of 100 mg/m2 followed by a 23-h continuous infusion of 230 mg/m2. In 5 of 20 patients partial remissions were achieved; 4 of these patients were primarily resistant against two TAD induction cycles. Bone marrow aplasia without a residual blast population was achieved in 7 of the 8 patients with primary TAD resistance. AMSA/etoposide thus seems to express an antileukemic efficacy without cross-resistance against TAD.

Aminoacridines↗
PubMed1985

Intensified induction and consolidation with or without maintenance chemotherapy for acute myeloid leukemia (AML): two multicenter studies of the German AML Cooperative Group.

In two multicenter trials, a total of 576 patients with acute myeloid leukemia (AML) were treated and found to be evaluable. Two hundred forty-two patients were in a 1978 pilot study and 334 patients were in a 1982 randomized study. Ages were between 15 and 78 years (median, 48). The uniform remission induction therapy in both studies consisted of one to two courses of a 9-day combination of 6-thioguanine (TG) with cytosine arabinoside (ARA-C) and daunorubicin (DNR) [TAD9]. The timing and sequencing of TAD9 was designed according to cell kinetic effects of ARA-C. A complete remission (CR) was achieved in 65% (70% and 61%, respectively) of patients within a median of 33 days, and in 68% of responders after only one course. The CR rate in patients 60 to 78 years of age was 51% (66% and 39%, respectively). In the 1978 pilot study, different protocols of post-remission treatment were applied at the different centers: monthly 5-day maintenance, TAD9 consolidation, both consolidation and maintenance, or no further therapy. The group receiving treatment during CR showed 24% probability of remissions at 4 years v 0% probability of remissions in the untreated group. Between the different post-remission protocols, no significant differences were observed. Remission duration was not influenced by age, WBC, or morphologic cell type, but was longer in patients achieving CR within 30 days (P = .017). In the subsequent 1982 study, 145 patients in CR were randomized for TAD9 consolidation with or without monthly maintenance. The updated life-table analysis revealed a predicted rate of continuous remission at 2 1/2 years of 30% for the maintenance and 17% for the nonmaintenance arm (P = .003). These results of response and remission duration in adult patients of all ages support the validity of intensified induction therapy and of consequent myelosuppressive treatment in remission.

Actuarial Analysis↗