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V Diehl

Publications and source records attributed to V Diehl.

At least 55 records · Page 3Linked to original sources
PubMed2002

Preclinical evaluation of the antiproliferative potential of STI571 in Hodgkin's disease.

STI571 is a selective tyrosine kinase inhibitor with proven therapeutic potential in malignancies expressing c-kit. A strong c-kit and stem cell factor expression was detected in the Hodgkin and Reed Sternberg cell line L1236, but not in 20 primary cases of classical Hodgkin's disease. Proliferation of L1236 cells was neither affected by addition of stem cell factor nor by neutralising anti-stem cell factor antibodies or STI571. Results suggest that patients with Hodgkin's disease may not benefit from therapy with STI571.

Benzamides↗
PubMed2002

Quantitative molecular monitoring of residual tumor cells in chronic lymphocytic leukemia.

New therapeutic approaches for the treatment of B-cell chronic lymphocytic leukemia (B-CLL) can induce remarkable responses. Molecular remissions have been observed occasionally after high-dose chemotherapy. Thus, new improved techniques to monitor residual tumor cells on a molecular basis in CLL are warranted. For this purpose, a real-time quantitative allele-specific oligonucleotide polymerase chain reaction (ASO-PCR) for patients with B-CLL was designed. In the present study, the PCR assay was standardized with identical cycling parameters as well as primer, probe, and MgCl(2) concentration for each patient. Ten patients were monitored with DNA samples obtained at 52 time points (median: 5.2 per patient). The median follow-up per patient was 11.4 months. Nine of ten patients had PCR-detectable residual tumor cells in the peripheral blood after therapy. One patient became PCR negative with a combination of fludarabine and rituximab after the end of treatment. The MRD levels in patients with detectable disease ranged from 0.002% to 10.1% after therapy. We conclude that real-time quantitative ASO-PCR can be utilized for quantitative molecular monitoring of minimal residual disease (MRD) in B-CLL patients in complete remission (CR), that new effective treatment approaches such as combined chemo/immunotherapy can render CLL patients PCR negative, and that different MRD levels in PCR-positive patients were observed warranting further investigation into possible correlation with clinical outcome.

Aged↗
PubMed2002

The in vitro anti-inflammatory effects of recombinant anti-CD25 immunotoxin on lamina propria T cells of patients with inflammatory bowel disease are not sufficient to cure experimental colitis in mice.

BACKGROUND AND AIMS: In chronic inflammatory bowel disease (IBD) such as Crohn's disease and ulcerative colitis an aberrant mucosal immune regulation is observed accompanied by upregulation of proinflammatory cytokines. Lamina propria T cells of inflamed mucosa have an activated phenotype characterized by increased expression of surface markers such as CD25. We therefore determined the anti-inflammatory effect of a recombinant immunotoxin consisting of an anti-CD25 single chain variable fragment (scFv) fused to a deletion mutant of Pseudomonas exotoxin A [RFT5(scFv)ETA'] on isolated lamina propria lymphocytes of patients with IBD and in the murine model of trinitrobenzene sulfonic acid (TNBS) induced colitis. PATIENTS AND/METHODS: Lamina propria lymphocytes of 25 patients with IBD and 19 control patients were stimulated in absence or presence of RFT5(scFv)ETA'. Interferon-gamma production was determined in the supernatant by ELISA and the induction of apoptosis by flow cytometry after propidium iodide staining. BALB/c mice received TNBS intrarectally and were treated with RFT5(scFv)ETA'. RESULTS: In vitro the administration of RFT5(scFv)ETA' significantly reduced interferon-gamma production and increased apoptosis in lamina propria lymphocytes isolated of inflamed mucosa. However, this contrainflammatory regulation did not result in gain of weight or increased life span in experimental colitis in vivo. CONCLUSION: In addition to the downregulation of the proinflammatory cytokine in vitro, RFT5(scFv)ETA' induced neither a direct nor a bystander effect in an in vivo model of colitis. Therefore our data do not support potential therapeutic implications of targeting CD25 by RFT5(scFv)ETA' in chronic IBD.

Adult↗
PubMed2002

Current treatment of follicular non-Hodgkin's lymphoma.

56200 new cases of NHL are expected to be diagnosed in the United States (US) per year. For reasons that are not fully understood, the number of new cases per year has nearly doubled in the past three decades. Most patients with follicular lymphoma are over 50 years of age and present with widespread disease at diagnosis. Nodal involvement is very common, often accompanied by splenic and bone marrow disease. Despite the advanced stage, the median survival ranges from 8 to 12 years. The vast majority of patients with advanced stage follicular lymphoma are not cured using the current therapeutic options. The rate of relapse is fairly consistent over time, even in patients who have achieved complete responses (CRs) to treatment. Therapeutic options in follicular NHL include watchful waiting, oral alkylating agents, purine nucleoside analogues, combination chemotherapy, interferon and monoclonal antibodies. Radiolabelled monoclonal antibodies, autologous or allogeneic bone marrow or peripheral stem cell transplantation are under current clinical evaluation. The approval of rituximab, an unconjugated chimeric antibody against the CD20 antigen for the treatment of relapsed follicular B-cell NHL marked a milestone in the development of antibody treatment. In addition, newer approaches like radioimmunoconjugates with myeloablative activity induced response rates of 80-100% in heavily pretreated patients. Various clinical trials combining monoclonal antibodies with conventional therapies are currently ongoing to determine whether these new biological agents will alter the natural history of follicular lymphoma.

Aged↗
PubMed2002

T-cell non-Hodgkin's lymphoma in adults: clinicopathological characteristics, response to treatment and prognostic factors.

T-cell NHL represent 10-15% of all malignant lymphomas making systematic prospective clinical trials difficult. Therefore, the prognostic significance of the T-cell phenotype has been a matter of controversy in recent years. In a retrospective analysis of 681 patients (pts) with NHL accrued from 1992 to 1997 at a single institution, 66 patients with T-cell NHL were identified. According to the REAL classification, histologies were as follows: 28 peripheral T-cell lymphomas (PTCL), 19 large cell anaplastic lymphoma (LCAL), 12 precursor lymphoblastic lymphoma (Lb), and seven AILD. Multiagent anthracycline containing regimens were used as initial therapy in 91% of cases. T-cell NHL represent 9.8% of all NHL patients at our institution accrued over a 6-year period. Overall response rate was 76%, 21% had progressive disease and 3% died during first line treatment. Mean overall survival (OS) was 8.22 +/- 0.94 years. There was a significant difference in OS between the four different histological subgroups (log rank P=0.0288). LCAL: mean OS 11.05 +/- 1.55 years (95% CI 8.00-14.09); LB: mean OS 7.09 +/- 1.40 years (95% CI 4.33-9.84); PTCL: mean 6.62 +/- 1.17 years (95% CI 4.33-8.90); AILD: 1.54 +/- 0.44 years (95% CI 0.67-2.40). OS was also significantly different for patients classified according to the International Prognostic Index (IPI)-score (log rank P = 0.002). Mean OS for patients with low risk, intermediate low risk, intermediate high risk and high risk was 10.46 +/- 1.02, 6.46 +/- 1.79, 4.50 +/- 1.20 and 1.15 +/- 0.46 years, respectively. Univariate analysis (log-rank test) for prognostic factors also revealed elevated LDH, B-symptoms and extranodal involvement as significant factors for OS. The presence of bulky disease (>7.5 cm), advanced stage III/IV and bone marrow involvement did not influence OS. In conclusion, it is evident that histological subtype and IPI-score have a strong prognostic impact on OS in pts with T-cell NHL. Thus, the distribution of risk factors in patients with T-cell NHL may be more important for OS than T-cell histology per se.

Aged↗
PubMed2002

Early-stage idiopathic (primary) myelofibrosis--current issues of diagnostic features.

Idiopathic myelofibrosis (IMF) is generally characterized by bone marrow (BM) fibrosis, anemia, splenomegaly and a leuko-erythroblastic blood picture. Although, histopathology is in keeping with the assumption of a stepwise evolution of the disease, little hematological data are available for patients with prefibrotic and early stages of disease. Therefore a clinicopathological study was performed that included firstly an exploratory sample of 68 patients with minor supportive therapy in whom BM biopsies during follow-up (41 +/- 32 months) revealed an evolution of a prefibrotic or very early fibrotic lesion into overt IMF. The validation sample consisted of 556 patients with pretreatment marrow specimens on admission. Diagnostic features and BM lesions were identical compared with the patients of the exploratory sample at their first examination. BM biopsies were processed by routine stainings including silver impregnation (reticulin fibers) and frequently also by immunohistochemistry to identify megakaryocytes and erythroid precursor cells more properly. Apart from minor hemorrhage and peripheral thrombosis patients with early stage IMF presented with non-specific symptoms including varying degrees of leukocytosis (51%), anemia (38%), a platelet count exceeding 600 x 10(9)/l (86%), splenomegaly (15%) and increase in leukocyte alkaline phosphatase (LAP) (24%) and serum lactate dehydrogenase (LDH) (20%). BM histology confirmed a moderate increase in hematopoiesis with a mixed granulocytic and megakaryocytic myeloproliferation, a reduction of erythroid precursors and significant megakaryocytic abnormalities. In keeping with the first BM examination of the exploratory sample no or only a borderline to slight increase in reticulin fibers was detectable, however, in 68 of 134 patients follow-up biopsies revealed a transition into overt IMF (intervals about three years). Median survival of this cohort with early-stage IMF was 129 months thus contrasting manifest IMF with an usually more unfavorable prognosis. Recognition of early stage IMF certainly alters the generally applied diagnostic criteria of this disorder. Regarding patients with associated thrombocytosis, differentiation from essential thrombocythemia is recommended. Moreover, characterization of early stage IMF probably exerts an impact on survival and may influence the decision to perform a BM transplantation.

Adult↗
PubMed2002

Genetic instability in Hodgkin's lymphoma.

Genetic instability is a characteristic feature of the malignant Hodgkin and Reed-Sternberg (HRS) cells in classical Hodgkin's lymphoma and the lymphocytic and histiocytic (L&H) cells in lymphocyte predominant Hodgkin's lymphoma. Genetic instability can be classified into four major categories: distinct DNA mutations (microsatellite instability); numerical aberrations (chromosomal instability); structural aberrations (translocation instability); and gains and losses of chromosomal regions. In Hodgkin's lymphoma (HL), HRS cells and L&H cells show somatically mutated clonally rearranged immunoglobulin genes, thus characterizing these cells genetically as germinal center B cells. These cells furthermore show mutations of oncogenes and tumor suppressor genes in some cases (p53, IkappaBalpha, CD95/Fas). They do not, however, display microsatellite instability, as they have a proficient mismatch repair machinery. In contrast, HRS and L&H cells frequently harbor recurrent but not specific numerical and structural aberrations as detected by classical cytogenetics and fluorescence in situ hybridization analysis. Results from molecular genetic studies using comparative genomic hybridization and allelotyping (LOH) indicate typical genetic patterns in HL with gains and losses of distinct chromosomal regions. In some instances, candidate genes possibly involved in the malignant transformation of HRS cells and L&H cells have been characterized (JAK2, c-REL, MDM2). In summary, using molecular genetics it might be possible in the near future to elucidate some of the complex genetic instabilities observed in HL.

Chromosome Aberrations↗
PubMed2002

Early response to chemotherapy: a surrogate for final outcome of Hodgkin's disease patients that should influence initial treatment length and intensity?

BACKGROUND: Early adjustment of treatment may benefit the patient. In order to guide treatment adjustment, use of early response (ER) or early complete response (ECR), judged after the few initial cycles of chemotherapy, is common in pediatric and also adult Hodgkin's and non-Hodgkin's studies. Paradoxically, almost no data support this strategy. PATIENTS AND METHODS: The influence of ECR on outcome was evaluated in three series of advanced Hodgkin's disease (HD), leading to a series of questions. RESULTS: The 1982 EORTC study assessed prospectively the time frame needed to reach an apparent complete response (CR) through repeated tumor measurements. In patients assessed at mid-treatment before the fifth cycle, both 15 year freedom from progression (FFP) and overall survival (OS) were superior in ECR patients compared with other patients continued on the same treatment (61% versus 37%; P < 0.001). A series of questions arise from these observations. Question 1: is the shortening of treatment detrimental? In a randomized Swedish trial, in one arm treatment was shortened in patients evaluated from the fifth cycle as ECR as compared with the standard eight cycles arm, 10 year cause-specific-survival (CSS) was 53 versus 69% [not significant (ns)]; 10 year OS 49% versus 58% (ns). Conversely, in the EORTC 20884 study, ECR patients given only six cycles did as well as patients entering CR later and, for this reason, given eight cycles (identical 6 year event-free survival 75%). Question 2: is early treatment adaptation in patients who failed to reach ER beneficial? In the French MDH 90 trial, 15% of children failed to reach ECR after four cycles; in these children only, anthracyclines plus alkylating agents were given and the dose of radiotherapy increased, improving the results observed in the previous trial. In the EORTC 20884 study, patients who failed to reach an ECR were switched earlier to involved field RT: their results matched those of ECR patients, at the difference of the previous trial. Question 3: is ER a predicting factor that can be used with any type of treatment? Probably not, based on the German Hodgkin's Lymphoma Study Group trial HD 9: ECR is highly dependent on specific interval from treatment start and on treatment intensity. DISCUSSION: More general questions stem from these results. Question 4: is the definition of ER secured? With conventional imaging, the different methods for response assessment at end treatment also lead to different response rates; the assessment in the middle of treatment itself and the use of newer imaging techniques may further increase the variation. Indeed, question 5 is: is ER a concept based on any biology? Correlation to markers, 99mTc uptake, PET and hematological tolerance might help to pinpoint how and why ER represents a surrogate for final outcome. CONCLUSION: ER is a surrogate for final outcome, reflecting both tumor burden and activity. This predictability may, and possibly should, impact on treatment.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2002

Current clinical trials for the treatment of advanced-stage Hodgkin's disease: BEACOPP.

BACKGROUND: The bleomycin-etoposide-doxorubicin-cyclophosphamide-vincristine-procarbazine-prednisone (BEACOPP) regimen was developed to investigate the potential of moderate dose escalation of conventional polychemotherapy to improve the unsatisfactory treatment results in advanced-stage Hodgkin's lymphoma (HL). Following pilot studies, the randomised trial HD 9 demonstrated that BEACOPP (baseline dose) attained superior failure-free survival to COPP/ABVD, and that dose escalation made a further marked improvement. Toxicity was severe but manageable. PATIENTS AND METHODS: The current GHSG multicentre randomised trial HD 12 has a 2 x 2 factorial design in order to make two comparisons: (i) eight cycles of escalated BEACOPP (as in HD9) are compared with four escalated cycles followed by four at baseline dose; (ii) the use of additional local radiotherapy to initial bulky disease and residual disease after chemotherapy is compared with chemotherapy alone, except where radiotherapy was prescribed by a central diagnostic panel. Eligible are patients aged 16-65 years with newly diagnosed HL of stage IIB with risk factors or stage III/IV. The EORTC multicentre trial 20012 randomises patients with HL stage III/IV to either eight cycles of ABVD or eight cycles of BEACOPP (four escalated + four baseline). RESULTS: The first interim analysis (January 2001) of HD 12 with 221 evaluable patients indicated continuation of recruitment. Recruitment will end in 2002 and the final data analysis will appear in 2006. CONCLUSIONS: The BEACOPP regimen is highly effective, and moderate dose escalation makes a further worthwhile improvement in tumour control. Current trials will measure BEACOPP against the international standard and show whether the amount of chemotherapy and/or radiotherapy can be reduced.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2002

Time-intensified dexamethasone/cisplatin/cytarabine: an effective salvage therapy with low toxicity in patients with relapsed and refractory Hodgkin's disease.

BACKGROUND: An important variable affecting outcome in relapsed and refractory Hodgkin's disease (HD) is the potential of conventional salvage chemotherapy to reduce tumor volume before high-dose chemotherapy (HDCT) and autologous stem cell transplantation. Currently, the optimal salvage chemotherapy regimen for these patients is unclear. Since dexamethasone/cisplatin/cytarabine (DHAP) given at 3-4 week intervals has been shown to be very effective in patients with relapsed aggressive non-Hodgkin's lymphoma, we evaluated this regimen given at a median of 16-day intervals in patients with relapsed and refractory HD. PATIENTS AND METHODS: Patients with relapsed or refractory HD were treated with two cycles of DHAP [dexamethasone 40 mg intravenously (i.v.) day 1-4, cisplatin 100 mg/m(2) i.v. as 24-h continuous infusion day 1, and cytarabine 2 g/m(2) i.v. 12q day 2]. Granulocyte colony-stimulating factor (G-CSF) was given at a dose of 5 micro g/kg from day 4 until day 13. Patients with partial remission (PR) or complete remission (CR) after two cycles of DHAP received sequential HDCT. RESULTS: The median age of the 102 patients included was 34 years (range 21-64 years). Forty-two percent of the patients had late relapse, 29% early relapse, 12% multiple relapse and 16% primary progressive/refractory disease. The response rate (RR) after two cycles of DHAP was 89% (21% CR, 68% PR). The RRs for patients with late, early, multiple and progressive HD were 91%, 93%, 92% and 65%, respectively. Using the chi-square test for independence, remission status (relapsed HD versus progressive HD) and stage at relapse (stage I/II versus stage III/IV) were significant factors for response to DHAP. WHO grade 4 leukocytopenia and thrombocytopenia were the main toxic- ities occurring in 43% (mean duration 1.1 days, range 0-6) and 48% (mean duration 1.4 days, range 0-11) of all courses, respectively. Neither severe infections nor treatment-related deaths occurred. Peripheral blood stem cells (PBSCs) were collected after the first cycle DHAP in eight patients. The hematopoietic progenitors showed a very rapid increase from day 10 with a synchronous and impressive peak on day 12. A mean of 6.1 x 10(6)/kg CD34(+) cells were collected per apheresis. As originally recommended in the protocol, PBSCs were routinely collected during sequential HDCT in the remaining patients. CONCLUSIONS: A brief tumor-reducing program with two cycles of DHAP given in short intervals supported by G-CSF is effective and well-tolerated in patients with relapsed and refractory HD. This regimen can be used to mobilize stem cells and select those patients with chemosensitive relapse who should subsequently be treated with HDCT.

Adolescent↗