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Biomedical subjects

A D Ho

Publications and source records attributed to A D Ho.

At least 37 records · Page 2Linked to original sources
PubMed2004

Micrometastatic bone marrow cells at diagnosis have no impact on survival of primary breast cancer patients with extensive axillary lymph node involvement treated with stem cell-supported high-dose chemotherapy.

BACKGROUND: To determine the impact of micrometastatic bone marrow cells (MMC) on survival in high-risk primary breast cancer (HRPBC) patients treated with high-dose chemotherapy (HDCT) and autologous stem cell transplantation (ASCT). PATIENTS AND METHODS: Ninety-one HRPBC patients (73 patients with > or =10 involved axillary lymph nodes (ALN), 18 premenopausal women with > or =4 involved ALN) received one cycle (eight patients) or two cycles of HDCT and ASCT. Bone marrow aspiration was performed before systemic treatment to search for MMC using a cocktail of four monoclonal epithelial-specific antibodies (5D3, HEA125, BM7 and BM8). The influence of MMC and other prognostic factors on disease-free survival (DFS), distant DFS (DDFS), and overall survival (OS) was analysed. RESULTS: In 23 of 91 patients (25%) we detected a median of three MMC (range, 1-43) among 10(6) mononuclear cells. With a median follow-up of 62 months (range, 10-117), the detection of MMC was not associated with DFS (P=0.929), DDFS (P=0.664) or OS (P=0.642). In multivariate analysis the strongest predictor was nodal ratio for DFS (P=0.012) and expression of p53 for OS (P <0.001). CONCLUSION: The detection of MMC at diagnosis has no impact on survival in HRPBC patients treated with HDCT and ASCT.

Adult↗
PubMed2004

Antiangiogenic therapy in hematologic malignancies.

Angiogenesis is defined as the formation of new capillaries from prexisting blood vessels and plays an important role in the progression of solid tumors and hematologic malignancies. Markers of angiogenesis correlate with clinical characteristics in leukemia and non-Hodgkin's-lymphoma, serving as predictors of poor prognosis. Antiangiogenic effects of chemotherapeutics as well as of novel drugs such as farnesyltransferase inhibitors and tyrosine kinase inhibitors such as Gleevec might contribute to their therapeutic potential. Thalidomide which has antiangiogenic effects and direct cytotoxic effects was found to be effective in multiple myeloma and is considered as an established treatment modality for patients with refractory or relapsed multiple myeloma. Thalidomide has a significant therapeutic effect in myelodysplastic syndrome (MDS) by improving cytopenia and achieving independence of transfusion therapy in a subset of patients. Preliminary data indicate activity of specific VEGF receptor tyrosine kinase (RTK) inhibitors in multiple myeloma (MM) and acute myeloid leukemia (AML). The positive correlation between increased levels of angiogenic cytokines and clinical response to VEGF-RTK inhibitors and thalidomide indicates the relevance of detecting angiogenesis markers to identify best candidate patients for specific approaches. Including antiangiogenic drugs into treatment protocols for hematologic malignancies is an important task for future clinical studies.

Angiogenesis Inhibitors↗
PubMed2003

Remarkable response to rituximab in a patient with atypical CD20(++) mantle cell lymphoma of the bone marrow leading to severe pancytopenia.

Rituximab, a chimeric monoclonal antibody which binds to the CD20 antigen, has been reported in several studies to induce remissions in low- and high-grade non-Hodgkin's lymphoma without causing myelosuppression. We report here a case of a 68-year-old female patient with an atypical mantle cell lymphoma infiltrating only the bone marrow without leukemic involvement or any other nodal or extranodal manifestations. Progressive severe pancytopenia due to the diffuse bone marrow infiltration led to life-threatening infections following oral chlorambucil treatment. No response to chlorambucil was noted. The patient attained a complete remission after salvage therapy with four weekly infusions of single-agent rituximab at a standard dose of 375 mg/m(2). Thus, anti-CD20 antibody may be the treatment of choice for patients with CD20(+) B-non-Hodgkin's lymphoma who cannot tolerate chemotherapy due to high risk of infectious complications as a result of severe pancytopenia.

Aged↗
PubMed2003

Peripherally inserted central venous catheters for autologous blood progenitor cell transplantation in patients with haematological malignancies.

BACKGROUND: In contrast to the high risk of haemorrhage associated with the implantation of a central venous catheter (CVC) via the internal jugular or subclavian access, the use of a peripherally inserted catheter (PICC) offers the advantage of a lower risk of bleeding complications. However, the rate of phlebitis is higher with the PICC and its use has been declining. We have studied the benefits and adverse events of a new type of PICC and a common type. METHODS: From October 1999 to October 2001, 70 PICCs (Olimpicc, Vygon, Germany, n=40; and LIFECATH-PICC(PUR)5FR Vygon, Germany, n=30) were inserted into 66 patients with haematological malignancies and used for high-dose chemotherapy, total parenteral nutrition and autologous blood stem cell transplantation. While removing the catheter, central and peripheral blood cultures were taken. The catheter tip was investigated by the semi-quantitative roll-out method of Maki. RESULTS: Sixty-five PICCs were removed after a median of 8.9 days. In five cases a catheter-associated significant colonisation with coagulase-negative staphylococci occurred. In two instances catheter-related bacteraemia was found. CONCLUSION: In our study this catheter system was inserted in 94% of patients without problems and showed a low incidence of phlebitis (5/65). Because of the high rate of catheter malfunction reported during and after our study, the Olimpicc catheter is no longer available. The PICC system, and the LIFECATH-PICC(PUR)5FR in particular, offers a safe and effective alternative for central venous access to the internal jugular vein.

Adult↗
PubMed2003

Evidence of a graft-versus-leukemia effect in chronic lymphocytic leukemia after reduced-intensity conditioning and allogeneic stem-cell transplantation: the Cooperative German Transplant Study Group.

PURPOSE: To study whether hematopoietic stem-cell transplantation (HSCT) after reduced-intensity conditioning is effective and tolerable in patients with advanced chronic lymphocytic leukemia (CLL). PATIENTS AND METHODS: Thirty patients with advanced B-cell CLL were included into the study. After reduced-intensity conditioning with fludarabine, busulfan, and antithymocyte globulin, patients received a transplant from related (n = 15) or unrelated donors (n = 15). Minimal residual disease (MRD) was monitored with a clone-specific polymerase chain reaction. RESULTS: After a median follow-up of 2 years, 23 patients are alive (to date). Neutrophil and platelet engraftment occurred after a median of 17.5 and 15 days, respectively. Acute graft-versus-host disease (GVHD) grade 2 to 4 was observed in 17 patients (56%), and chronic GVHD was observed in 21 patients (75%). Twelve patients (40%) achieved a complete remission (CR), and 16 patients (53%) achieved a partial remission. Late CR occurred up to 2 years after transplantation. MRD was monitored in eight patients with CR. All patients achieved a molecular CR. At last follow-up, six patients were in ongoing molecular CR. Causes of death were treatment-related complications in four patients and progressive disease in three patients. The probability of overall survival, progression-free survival, and nonrelapse mortality at 2 years was 72% (95% confidence interval [CI], 54% to 90%), 67% (95% CI, 49% to 85%), and 15% (95% CI, 1% to 29%), respectively. CONCLUSION: Treatment-related mortality after reduced-intensity conditioning followed by allogeneic HSCT was low. The procedure induced molecular remissions in patients with advanced CLL. The observation of late remissions provided evidence of a graft-versus-leukemia effect.

Adult↗
PubMed2003

[Multiple myeloma. Diagnosis and therapy].

Multiple myeloma is one of the 20 most frequent malignancies in Germany. Initial symptoms are usually non-specific. Assessment of bone marrow and laboratory data as well as imaging techniques are essential for diagnosis and prognostic evaluation. Data from molecular cytogenetics have led to a better understanding of the pathogenesis of multiple myeloma. Cytostatic therapy with alcylating agents and glucocorticoids prolongs the survival. High-dose therapy followed by transplantation of autologous hematopoietic stem cells improves prognosis for patients up to the age of 70. Currently, modifications of allogeneic hematopoietic stem cell transplantation, anti-angiogeneic and immunomodulatory drugs as well as proteasome inhibitors are evaluated in clinical trials. Supportive care has derived benefit from the introduction of new bisphosphonates.

Antineoplastic Agents↗
PubMed2003

Angiogenesis in hematologic malignancies.

Angiogenesis is defined as the formation of new capillaries from preexisting blood vessels and plays an important role in the progression of solid tumors. Recently a similar relationship has been described in several hematologic malignancies. Expression of the angiogenic peptides vascular endothelial growth factor (VEGF) and basic fibroblast growth factor correlates with clinical characteristics in leukemia and non-Hodgkin's-lymphoma and the serum/plasma concentrations serve as predictors of poor prognosis. Increased bone marrow microvessels in multiple myeloma (MM) are correlated with decreased overall survival. Thalidomide which has antiangiogenic effects and direct cytotoxic effects was found to be effective in MM, myelodysplastic syndrome and acute myeloid leukemia (AML). Preliminary data indicate activity of VEGF-tyrosine kinase inhibitors in AML. Clinical research is now aimed at testing antiangiogenic treatment strategies in several hematologic neoplasms as well as identifying the best candidate patients for specific approaches.

Cell Communication↗
PubMed2003

Centrosome aberrations as a possible mechanism for chromosomal instability in non-Hodgkin's lymphoma.

Recently, centrosome aberrations have been described as a possible cause of aneuploidy in many solid tumors. To investigate whether centrosome aberrations occur in non-Hodgkin's lymphoma (NHL) and correlate with histologic subtype, karyotype, and other biological disease features, we examined 24 follicular lymphomas (FL), 18 diffuse large-B-cell lymphomas (DLCL), 33 mantle cell lymphomas (MCL), and 17 extranodal marginal zone B-cell lymphomas (MZBCL), using antibodies to centrosomal proteins. All 92 NHL displayed numerical and structural centrosome aberrations as compared to nonmalignant lymphoid tissue. Centrosome abnormalities were detectable in 32.3% of the cells in NHL, but in only 5.5% of lymphoid cells from 30 control individuals (P<0.0001). Indolent FL and MZBCL contained only 25.8 and 28.8% cells with abnormal centrosomes. In contrast, aggressive DLCL and MCL harbored centrosome aberrations in 41.8 and 35.0% of the cells, respectively (P<0.0001). Centrosomal aberrations correlated to lymphoma grade, mitotic, and proliferation indices, but not to the p53 labeling index. Importantly, diploid MCL contained 31.2% cells with abnormal centrosomes, while tetraploid samples harbored centrosome aberrations in 55.6% of the cells (P<0.0001). These results indicate that centrosome defects are common in NHL and suggest that they may contribute to the acquisition of chromosomal instability typically seen in NHL.

Cell Division↗
PubMed2003

Addition of a low fixed number of CD3+ cells to CD34-enriched allografts: effects on engraftment, graft-versus-host disease, and survival after related and unrelated peripheral stem cell transplantation.

Despite prophylaxis with immunosuppressive drugs, severe graft-versus-host disease (GVHD) remains a major cause of morbidity and mortality following allogeneic stem cell transplantation. T cell depletion of the graft has decreased incidence and severity of GVHD but has resulted in a higher incidence of graft failure and relapse. To reduce the risk of severe GVHD, but at the same time to maintain the graft-versus-tumor effect, we administered a fixed low number of 1 x 10(5) donor T cells per kilogram of body weight to recipients of CD34(+) cell-enriched allogeneic peripheral blood stem cells (PBSCs). Donor lymphocyte infusions (DLI) were then given in incremental doses when mixed chimerism persisted or signs of relapse occurred. A total of 23 patients receiving allografts from related and unrelated donors were treated according to this protocol after myeloablative or reduced intensity conditioning. One patient did not engraft and 3/20 evaluable patients developed acute (a) GVHD > or = grade II, with a corresponding estimated cumulative incidence of 15.6% (95% CI 0-30.5%). DLI (n = 13) induced aGVHD > or = II in 6 patients, but the severity of the syndrome was reduced. Overall GVHD-related mortality was low (13%). The probability of disease-free survival and overall survival at 2 years was 0.40 (95% CI 0.21-0.75) and 0.36 (95% CI 0.21-0.63). Progression-free survival and overall survival was significantly better in patients with acute or chronic myelogenous leukemia compared to patients with lymphoproliferative disorders (p = 0.002; p = 0.02). We conclude that the combination of allografts with a T cell content of about 1 x 10(5)/kg and escalating doses of DLI is a viable transplant strategy in patients with myeloid leukemias, which results in stable engraftment and a reduction of mortality from aGVHD.

Adult↗
PubMed2003

Improved clinical outcome of lupus nephritis during the past decade: importance of early diagnosis and treatment.

OBJECTIVE: To evaluate the differences in the outcome of lupus nephritis diagnosed either in the 1980s or the 1990s in Heidelberg, Germany. METHODS: Fifteen patients with biopsy confirmed lupus nephritis (LN) were followed up between 1980 and 1989 and 41 patients were followed up between 1990 and 2000. Their status at diagnosis and their treatment schedules and outcome were analysed. 68% had WHO IV nephritis. RESULTS: In the decade from 1990 to 2000 there was significantly less proteinuria (46 v 17 g/l, p=0.008), significantly lower rates of renal failure (40% v 17%, p=0.02), and fewer histological signs of chronicity (33% v 10%, p=0.01) at the time of diagnosis of LN than in the decade from 1980 to 1989. The mean (SD) time from the first appearance of proteinuria until kidney biopsy was significantly shorter in the later decade (15.4 (15.6) v 3.9 (4.7) months). Although treatment schedules were not significantly different, the outcome of the disease was significantly better in the patients who were diagnosed with LN between 1990 and 2000 (p=0.045). Whereas 6/15 (40%) patients between 1980 and 1989 had terminal renal failure after a mean time of 94 months, in the group of 1990-2000 no patient developed terminal renal failure (median observation time 24 months). In both groups one patient died from infection. A high chronicity index in histology and the presence of arterial hypertension or renal failure, or both, at the time of diagnosis were significant risk factors for the development of terminal renal failure in the course of the disease. CONCLUSIONS: The outcome of patients with newly diagnosed LN was significantly better between 1990 and 2000 than between 1980 and 1989. Kidney damage and chronic histological changes at time of diagnosis were significantly less common between 1990 and 2000, which is attributable to earlier diagnosis and treatment in the later decade.

Adolescent↗
PubMed2003

Use of erythropoietin in patients with multiple myeloma.

The prevalence of tumour anaemia in patients with multiple myeloma is greater than 80%. At the time of diagnosis 20% of these patients are already anaemic. In about 70% of patients with multiple myeloma, recombinant human erythropoietin (r-HuEPO) leads to a reduction in transfusion frequency, resulting in a drop in transfusion- related side-effects like infections and immune reactions, iron overload and hyperviscosity which often negatively influence the course of disease. A further reason for the use of erythropoietin is to achieve and maintain high haemoglobin levels (11-12 g/dl), which are of considerable prognostic significance in patients with multiple myeloma. Increasing Hb levels with r-HuEPO also improve the quality of life of patients, thus leading to better therapy compliance. The trade-off between high costs of an erythropoietin treatment and lower indirect costs (infusion material, personal equipment, patient transport costs, etc.) should be evaluated. Nevertheless, an exact definition of patients for whom the use of erythropoietin is beneficial is warranted. The pathogenesis of anaemia and the clinical experiences of erythropoietin in patients with multiple myeloma are discussed.

Anemia↗
PubMed2003

Imatinib restores expression of CD62L in BCR-ABL-positive cells.

Chronic myelogenous leukemia (CML) is characterized by aberrant trafficking of malignant hematopoietic progenitor cells in the peripheral blood. Expression of the cell adhesion molecule CD62L was reported to be significantly lower in CML patients than in normal controls. We studied whether the transcription of CD62L in CML cells is dependent on the activity of the BCR-ABL tyrosine kinase. Following addition of the Abelson (ABL) tyrosine kinase inhibitor imatinib (formerly STI571) to two BCR-ABL-positive cell lines (BV173, SD-1), we observed a dose-dependent increase in CD62L RNA levels of up to 45-fold by a quantitative, real-time polymerase chain reaction and an increase in the amount of cell surface-bound CD62L of up to 18-fold by quantitative flow cytometry, respectively. These data are validated by an increased CD62L expression in the bone marrow of patients (n=6) with advanced CML who received imatinib. Restoration of defective cell adhesion mediated via the CD62L pathway may be one mechanism of action of imatinib in BCR-ABL-positive leukemias.

Antineoplastic Agents↗
PubMed2002

Gangrene of the toes in a patient with chronic myelogenous leukemia after long-term hydroxyurea therapy.

Gangrene of the toes and digits appears to be a rare but very severe complication of long-term hydroxyurea therapy. Nothing is known regarding the pathophysiology and the type of vascular damage leading to this syndrome. Here we report a case of a 49-year-old male presenting with gangrene of the toes of both feet 4.5 years after initiation of hydroxyurea therapy for chronic myelogenous leukemia. Blisters on the toes occurred for the first time 9 months prior to hospitalization. Successively, all ten toes showed signs of beginning gangrene with one toe removed surgically 8 months before admission. Presence of diabetes mellitus or peripheral angiopathy was ruled out and platelet counts were within the physiologic range during the last years, excluding thrombocythemia as another rare cause for gangrene in patients with myeloproliferative diseases. Whereas perimalleolar ulcerations of the legs are a more common complication of hydroxyurea, gangrene of the toes as a consequence of hydroxyurea treatment has been described previously only once in the literature. At this point in time cessation of hydroxyurea treatment appears to be the only therapeutic option, thereby avoiding further progress of gangrene in patients with chronic myelogenous leukemia treated with hydroxyurea.

Antineoplastic Agents↗
PubMed2002

Rationale for combination therapy of chronic myelogenous leukaemia with imatinib and irradiation or alkylating agents: implications for pretransplant conditioning.

The tyrosine kinase activity of the BCR-ABL oncoprotein results in reduced apoptosis and thus prolongs survival of chronic myelogenous leukaemia cells. The tyrosine kinase inhibitor imatinib (formerly STI571) was reported to selectively suppress the proliferation of BCR-ABL-positive cells. Assuming that imatinib could be included in pretransplantation conditioning therapies, we tested whether combinations of imatinib and gamma-irradiation or alkylating agents such as busulfan or treosulfan would display synergistic activity in BCR-ABL-positive chronic myelogenous leukaemia BV173 and EM-3 cell lines. Further, primary cells of untreated chronic myelogenous leukaemia patients were assayed for colony forming ability under combination therapy with imatinib. Additionally, the cytotoxic effect of these combinations on BCR-ABL-negative cells was investigated. In the cell lines a tetrazolium based MTT assay was used to quantify growth inhibition after exposure to cytotoxic drugs alone or to combinations with imatinib. Irradiation was applied prior to exposure to imatinib. Interaction of drugs was analysed using the median-effect method of Chou and Talalay. The combination index was calculated according to the classic isobologram equation. The combination imatinib + gamma-irradiation proved to be significantly synergistic over a broad range of cell growth inhibition levels in both BCR-ABL-positive cell lines and produced the strongest reduction in primary chronic myelogenous leukaemia colony-forming progenitor cells. Combinations of imatinib + busulfan and imatinib + treosulfan showed merely additive to antagonistic effects. Imatinib did not potentiate the effects of irradiation or cytotoxic agents in BCR-ABL-negative cells. Our data provide the basis to further develop imatinib-containing conditioning therapies for stem cell transplantation in chronic myelogenous leukaemia.

Antineoplastic Agents↗
PubMed2002

Occurrence of sarcoidosis subsequent to chemotherapy for non-Hodgkin's lymphoma: report of two cases.

Sarcoidosis-lymphoma syndrome is a well-established syndrome where sarcoidosis is followed by the development of a lymphoproliferative disease such as non-Hodgkin's lymphoma (NHL). Here we report two patients with NHL who developed sarcoidosis subsequent to the diagnosis of lymphoproliferative disease. In both cases, chemotherapeutic treatment had already been initiated or was completed when sarcoidosis occurred. In these patients, sarcoidosis may have been triggered by immunologic aberrations induced by antineoplastic therapy or as a consequence of an underlying immunologic disturbance associated with the lymphoma. When a suspected relapse of lymphoma presents with signs and symptoms compatible with sarcoidosis, this rare immunologic disorder has to be ruled out by careful clinical and histopathologic analysis to prevent mistreatment.

Adult↗