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Biomedical subjects

R Hehlmann

Publications and source records attributed to R Hehlmann.

At least 55 records · Page 3Linked to original sources
PubMed2003

Treatment of a patient with advanced esophageal cancer with a combination of mitomycin C and capecitabine: activation of the thymidine phosphorylase as active principle?

BACKGROUND: Both capecitabine, an oral prodrug of 5-fluorouracil (5-FU), and mitomycin C (MMC) have demonstrated activity as single agents in patients with gastrointestinal cancer. Furthermore, a combination of MMC with infusional 5-FU can induce tumor remission even in patients pretreated with 5-FU. Capecitabine and MMC act synergistically due to an upregulation of the thymidine phosphorylase activity by MMC in a human xenograft model. PATIENT: We sought to exploit these preclinically observed effects in a patient with esophageal cancer who was progressive after a first-line radiochemotherapy with 5-FU and cisplatin. He was treated with a combination of MMC and capecitabine on a compassionate use basis. A rapid remission lasting for about 6 months was observed. CONCLUSION: This is the first report on a combination therapy with capecitabine and MMC. The remission observed in our patient suggests that the preclinically observed synergy has clinical impact. This combination should be further investigated in prospective clinical trials.

Adult↗
PubMed2003

Treatment of relapsed acute promyelocytic leukemia.

By all-trans retinoic acid (ATRA) and chemotherapy over 70% of patients with newly diagnosed acute promyelocytic leukemia (APL) may be cured; 20-30% of patients still relapse and require salvage therapy. For relapsed or refractory APL, a standard treatment has not yet been defined. However, several effective drugs and approaches have been described. Treatment options for relapsed APL include chemotherapy regimens used in the treatment of relapsed acute myeloid leukemia usually combined with ATRA or of other differentiating agents such as liposomal ATRA or synthetic retinoids. Presently, allogeneic peripheral stem cell or bone marrow transplantation is the treatment of choice for younger patients who have a histocompatible donor, as it gives the chance of cure in second or further relapse. For patients without a donor or for those who are not suitable for allogeneic transplantation, autologous stem cell or bone marrow transplantation may offer at least the possibility of a prolongation of remission, if the harvested cells are negative in the RT-PCR of PML/RAR alpha. Arsenic compounds have a high antileukemic effectiveness on APL cells. Arsenic trioxide has recently been approved for relapsed or refractory APL. With this drug, complete hematologic remission rates of 80-92% and long-lasting molecular remissions were achieved in relapsed patients. For patients who do not qualify for these treatment options, monoclonal anti-CD33 antibodies may represent further treatment options.

Antineoplastic Agents↗
PubMed2002

Auer rod-like inclusions in multiple myeloma.

We report a case of IgA multiple myeloma, in which the plasma cells showed multiple azurophilic, Auer rod-like intracytoplasmic inclusions in May-Grünwald-Giemsa-stained marrow smears. Cytochemical stainings revealed a strong alpha-N-esterase activity of these inclusions, whereas the reactions for peroxidase, Sudan black, chloroacetate esterase, and PAS were negative. Immunostaining verified IgA-kappa inside the plasma cells. The inclusions, however, were negative. Amyloid and lysozyme were also not detectable. Electron microscopy showed Auer rod-like inclusions with a smooth surface in the neighborhood of a well-developed rough endoplasmic reticulum, but with no direct relation to it. The inclusions showed a fine lamellar substructure, and the periodicity of the filamentous striations was about 10 nm, comparable with the substructure of typical Auer rods. Our findings suggest that the azurophilic inclusions in multiple myeloma are Auer rod-related structures, which likewise consist of active lysosomal enzymes. In contrast to the Auer rods in acute myeloblastic leukemia (AML), however, the inclusions in multiple myeloma consist of typical plasma cell enzymes.

Azure Stains↗
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

Comparison of chromosome banding analysis, interphase- and hypermetaphase-FISH, qualitative and quantitative PCR for diagnosis and for follow-up in chronic myeloid leukemia: a study on 350 cases.

For the diagnosis of CML and for monitoring of treatment response the detection of the t(9;22)(q34;q11) or the BCR-ABL rearrangement is necessary. Chromosome banding analysis (CA) is still the gold standard but other techniques like Southern blot, fluorescence in situ hybridization (FISH) and polymerase chain reaction (PCR) are available. We analyzed 350 CML patients at different stages of disease in parallel with CA, interphase-FISH (IP-FISH), hypermetaphase-FISH (HM-FISH) and RT-PCR. In 20 cases with no Ph(+) metaphases in CA, HM-FISH detected 0.2 to 10% BCR-ABL(+)metaphases. After IP-FISH 107 samples were judged as negative. However, in 17 of these samples HM-FISH detected BCR-ABL(+) metaphases (0.3-11%), and in eight cases CA detected Ph(+) metaphases (2.5-25%). A comparison of IP-FISH performed on uncultivated cells vs cells cultivated for 48 h in 70 cases revealed a higher proportion of BCR-ABL+ cells in the cultivated samples. If nested PCR was negative, all other methods were negative in all cases too. In addition, 94 cases were evaluated using real-time PCR (LightCycler technology). The BCR-ABL/cABL ratio measured showed a high correlation with all other methods. Interestingly, a wide range in the BCR-ABL/ABL ratio was observed especially in patients who showed 100% Ph-positive metaphases in CA. In conclusion, CA, IP-FISH, HM-FISH and real-time PCR give reliable results but differences due to measurement of different target structures have to be kept in mind when using these data for definition of remission status.

B-Lymphocytes↗
PubMed2002

Safety and efficacy of STI-571 (imatinib mesylate) in patients with bcr/abl-positive chronic myelogenous leukemia (CML) after autologous peripheral blood stem cell transplantation (PBSCT).

We examined safety and efficacy of STI-571 in 24 bcr/abl-positive patients with CML post PBSCT. At start of STI-571 therapy, nine patients presented in blast crisis (BC) or in accelerated phase (AP), and 15 in chronic phase (CP). Patients were evaluated for hematologic, cytogenetic and molecular response, survival and toxicity. In general, STI-571 was well tolerated in this heavily pretreated group of patients with a non-hematologic and hematologic toxicity profile similar to that observed in a previous phase I trial at comparable doses. Five of nine patients with CML in transformation (AP, BC) were evaluable for hematologic response. Two of five patients had transient reductions in WBC and blasts, and three patients achieved a sustained hematologic response (>4 weeks). Cytogenetic analysis in these patients revealed numerical and/or structural responses. In CML chronic phase, STI-571 induced complete hematologic responses in all patients and major cytogenetic responses in 61% of patients with a complete cytogenetic response rate of 46%. This report indicates that STI-571 is a safe and effective drug in heavily pretreated patients. No apparent additional side-effects were noted in this patient cohort. The high rate of complete hematologic and complete cytogenetic responses in CP patients is remarkable, as intensive treatment approaches plus IFN-alpha failed to be efficient in achieving long-term stabilization of CML in this patient cohort.

Adult↗
PubMed2002

Alterations of the cyclin D1/pRb/p16(INK4A) pathway in multiple myeloma.

The retinoblastoma protein (pRb), p16(INK4A), D-type cyclins, and their partners cyclin-dependent kinase (CDK) 4 and 6 constitute a G(1) regulatory pathway commonly targeted in tumorigenesis. Several malignancies show a reciprocal correlation between genetic alterations of single members of the pRb pathway. Therefore, we determined the frequency of Rb deletions and cyclin D1 alterations by fluorescence in situ hybridization as well as 5' CpG island hypermethylation of the p16(INK4A)gene using methylation-specific polymerase chain reaction in bone marrow mononuclear cells from 82 individuals with plasma cell disorders. Alterations in at least one of the components of the pathway were found in 75%. Cyclin D1 translocations or amplifications were detected in 14/82 (17.1%), Rb deletions at 13q14 in 23/82 (28%) of the cases, including three (3.6%) homozygous deletions. p16(INK4A) was hypermethylated in 33/57 (57.9%) of the samples. Further analysis revealed a highly significant correlation between cyclin D1 alterations and extramedullar or leukemic myeloma manifestations (P = 0.014; Fisher's test). Whereas Rb deletions seemed to occur alternatively to cyclin D1 alterations, no reciprocal correlation was found between p16(INK4A) hypermethylations and cyclin D1 or Rb locus aberrations. Cyclin D1 locus alterations and Rb deletions were associated with a significantly worse prognosis whereas p16(INK4A) hypermethylation had no impact on survival. We conclude that cyclin D1 and Rb aberrations seem to occur as alternative events in plasma cell malignancies and contribute to clinical course and prognosis. In contrast, although p16(INK4A) hypermethylation is frequent, inactivation of p16(INK4A) seems not to be involved in the pathogenesis of plasma cell disorders.

Chromosome Aberrations↗
PubMed2002

Early reduction of BCR-ABL mRNA transcript levels predicts cytogenetic response in chronic phase CML patients treated with imatinib after failure of interferon alpha.

The degree of tumor load reduction as measured by cytogenetic response is an important prognostic factor for chronic myelogenous leukemia (CML) patients on therapy. We sought to determine whether BCR-ABL transcript levels can predict chromosomal response. Residual disease was evaluated in 120 CML patients in chronic phase (CP) treated with the selective tyrosine kinase inhibitor imatinib after resistance or intolerance to interferon alpha (IFN). Median time of therapy was 401 days (range 111-704). BCR-ABL and total ABL transcripts were measured in 486 peripheral blood (PB) specimens with a real time RT-PCR approach using fluorescent-labeled hybridization probes (LightCycler technology) and results were expressed as the ratio BCR-ABL/ABL. Cytogenetic response was determined in 3-monthly intervals: From 101 evaluable patients, 42 achieved a complete (CR, 0% Philadelphia chromosome (Ph)- positive metaphases), 18 a partial (PR, 1-34% Ph+), 13 a minor (MR, 35-94% Ph+), and 26 no response (NR, >94% Ph+). All PB samples were RT-PCR positive. The proportion of Ph+ metaphases and simultaneous BCR-ABL/ABL ratios correlated with r = 0.74, P < 0.0001. In order to investigate whether early molecular analysis may predict cytogenetic response, quantitative RT-PCR data obtained after 1 and 2 months of therapy were compared with cytogenetic response at 6 months. BCR-ABL/ABL ratios after 1 month were not predictive, but results after 2 months correlated with the consecutive cytogenetic response (P = 0.0008). The probability for a major cytogenetic response was significantly higher in patients with a BCR-ABL/ABL ratio <20% after 2 months of imatinib therapy. We conclude that: (1) quantitative determination of residual disease with real time RT-PCR is a reliable and sensitive method to monitor CML patients on imatinib therapy; (2) BCR-ABL/ABL ratios correlate well with cytogenetic response; (3) in IFN-pretreated patients all complete responders to imatinib have evidence of residual disease with the limited follow-up available; and (4) cytogenetic response at 6 months of therapy in CP patients is predictable with real time RT-PCR at 2 months.

Adult↗
PubMed2002

Improvement of molecular monitoring of residual disease in leukemias by bedside RNA stabilization.

The sensitivity of assays designed to monitor minimal residual disease (MRD) by RT-PCR in leukemia depend on quality and quantity of RNA derived from peripheral blood (PB) and bone marrow (BM) leukocytes. Shipment of material may lead to RNA degradation resulting in a loss of sensitivity and, potentially, false negative results. Furthermore, degradation may lead to inaccurate estimates of MRD in positive specimens. We sought to determine feasibility and efficacy of a novel blood collection and processing system which is based on integrated RNA stabilization at the time of phlebotomy (PAXgene Blood RNA Kit) by comparison with standard methods of RNA extraction (cesium chloride gradient ultracentrifugation and RNeasy Mini Kit) using unstabilized EDTA anticoagulated PB. In 26 patients with chronic myelogenous leukemia (CML) on therapy, PB was processed after a storage time at room temperature of 2 and 72 h according to these protocols. BCR-ABL, total ABL and glucose-6-phosphate dehydrogenase (G6PD) mRNA transcripts of PB samples were quantified as a measure for response to therapy and RNA integrity. RNA yield expressed as the ratio of ABL transcripts after a storage time of 72 h/ABL transcripts after a storage time of 2 h at room temperature was significantly higher with the stabilizing method (median 0.40) compared to the RNeasy method using unstabilized PB (median 0.13, P = 0.01). Furthermore, ratios BCR-ABL/ABL after 72 vs 2 h still correlated well using the PAXgene method (r = 0.99, P < 0.0001) in contrast to the standard method which did not (r = 0.65, P = 0.03). Even investigation of complete cytogenetic responders with very low tumor burden showed a good correlation of ratios BCR-ABL/ABL compared to the reference method. Comparable results were achieved using G6PD transcripts as standard. We conclude that the new PAXgene stabilization method could improve RNA quality and the comparability of molecular monitoring within and between multicenter trials.

Adult↗
PubMed2002

Molecular and chromosomal mechanisms of resistance to imatinib (STI571) therapy.

Selective inhibition of the BCR-ABL tyrosine kinase by imatinib (STI571, Glivec/Gleevec) is a promising new therapeutic strategy in patients with chronic myelogenous leukemia (CML). Despite significant hematologic and cytogenetic responses, resistance occurs, particularly in patients with advanced disease. We sought to determine the underlying mechanisms. Sixty-six patients with CML in myeloid blast crisis (n = 33), lymphoid blast crisis (n = 2), accelerated phase (n = 16), chronic phase (n = 13), and BCR-ABL-positive acute lymphoblastic leukemia (n = 2) resistant to imatinib were investigated. Median duration of imatinib therapy was 148 days (range 6-882). Patients were evaluated for genomic amplification of BCR-ABL, overexpression of BCR-ABL transcripts, clonal karyotypic evolution, and mutations of the imatinib binding site in the BCR-ABL tyrosine kinase domain. Results were as follows: (1) Median levels of BCR-ABL transcripts, were not significantly changed at the time of resistance but 7/55 patients showed a >10-fold increase in BCR-ABL levels; (2) genomic amplification of BCR-ABL was found in 2/32 patients evaluated by fluorescence in situ hybridization; (3) additional chromosomal aberrations were observed in 19/36 patients; (4) point mutations of the ABL tyrosine kinase domain resulting in reactivation of the BCR-ABL tyrosine kinase were detected in 23/66 patients. In conclusion, although the heterogeneous development of imatinib resistance is challenging, the fact that BCR-ABL is active in many resistant patients suggests that the chimeric oncoprotein remains a good therapeutic target. However, patients with clonal evolution are more likely to have BCR-ABL-independent mechanisms of resistance. The observations warrant trials combining imatinib with other agents.

Antineoplastic Agents↗
PubMed2002

[Echocardiographic detection of tricuspid valve endocarditis and right atrial and ventricular masses in a patient with acute myeloid leukaemia].

In a patient with acute leukaemia, tricuspid valve vegetations and both right atrial and ventricular masses formed within a few weeks were detected by echocardiography. In addition to endocarditis which is a very rare condition in patients with acute leukaemia, the diagnostic efforts including cardiac surgery resulted in the unusual finding of right-sided cardiac thrombi which had formed autochthonously. The most likely cause was thought to be a very severe systemic infection with staphylococci characterised by repeated episodes of bacteraemia during profound and prolonged neutropenia as well as a paraneoplastic coagulopathy. Surgery performed on the grounds of the echocardiography findings and differential-diagnostic considerations resulted in the relapse-free removal of the infectious focus. The maintenance therapy for leukaemia could thus be continued and led to a distinctly improved outcome. This case report confirms the great importance of sonography in the management of fever of unknown origin in immunocompromised patients.

Acute Disease↗
PubMed2002

High-dose 5-fluorouracil / folinic acid in combination with three-weekly mitomycin C in the treatment of advanced gastric cancer. A phase II study.

BACKGROUND: The 24-hour continuous infusion of 5-fluorouracil (5-FU) and folinic acid (FA) as part of several new multidrug chemotherapy regimens in advanced gastric cancer (AGC) has shown to be effective, with low toxicity. In a previous phase II study with 3-weekly bolus 5-FU, FA and mitomycin C (MMC) we found a low toxicity rate and response rates comparable to those of regimens such as ELF, FAM or FAMTX, and a promising median overall survival. In order to improve this MMC-dependent schedule we initiated a phase II study with high-dose 5-FU/FA and 3-weekly bolus MMC. PATIENTS AND METHODS: From February, 1998 to September, 2000 we recruited 33 patients with AGC to receive weekly 24-hour 5-FU 2,600 mg/m(2) preceded by 2-hour FA 500 mg/m(2) for 6 weeks, followed by a 2-week rest period. Bolus MMC 10 mg/m(2) was added in 3-weekly intervals. Treatment given on an outpatient basis, using portable pump systems, was repeated on day 57. Patients' characteristics were: male/female ratio 20/13; median age 57 (27-75) years; median WHO status 1 (0-2). 18 patients had a primary AGC, and 15 showed a relapsed AGC. Median follow-up was 11.8 months (range of those surviving: 2.7-11.8 months). RESULTS: 32 patients were evaluable for response - complete remission 9.1% (n = 3), partial remission 45.5% (n = 15), no change 27.3% (n = 9), progressive disease 15.1% (n = 5). Median overall survival time was 10.2 months [95% confidence interval (CI): 8.7-11.6], and median progression-free survival time was 7.6 months (95% CI: 4.4-10.9). The worst toxicities (%) observed were (CTC-NCI 1/2/3): leukopenia 45.5/18.2/6.1, thrombocytopenia 33.3/9.1/6.1, vomitus 24.2/9.1/0, diarrhea 36.4/6.1/3.0, stomatitis 18.2/9.1/0, hand-foot syndrome 12.1/0/0. Two patients developed hemolytic-uremic syndrome (HUS). CONCLUSIONS: High-dose 5-FU/FA/MMC is an effective and well-tolerated outpatient regimen for AGC (objective response rate 54.6%). It may serve as an alternative to cisplatin-containing regimens; however, it has to be considered that possibly HUS may occur.

Adenocarcinoma↗
PubMed2001

Chronic myeloid leukemia and interferon-alpha: a study of complete cytogenetic responders.

Achieving a complete cytogenetic response (CCgR) is a major target in the treatment of chronic myeloid leukemia (CML) with interferon-alpha (IFN-alpha), but CCgRs are rare. The mean CCgR rate is 13%, in a range of 5% to 33%. A collaborative study of 9 European Union countries has led to the collection of data on 317 patients who were first seen between 1983 and 1997 and achieved CCgRs with IFN-alpha alone or in combination with hydroxyurea. The median time to first CCgR was 19 months (95% CI, 17-21; range, 3-84 months). At last contact, 212 patients were still alive and in continuous CCgR; 105 patients had lost CCgR, but 53% of them were still alive and in chronic phase. IFN-alpha treatment was discontinued permanently in 23 cases for response loss, in 36 cases for chronic toxicity (15 are still in unmaintained continuous CCgR), and in 8 cases because it was believed that treatment was no longer necessary (7 of these 8 patients are still in unmaintained continuous CCgR). The 10-year survival rate from first CCgR is 72% (95% CI, 62%-82%) and is related to the risk profile. High-risk patients lost CCgR more frequently and more rapidly and none survived more than 10 years. Low-risk patients survived much longer (10-year survival probability 89% for Sokal low risk and 81% for Euro low risk). These data point out that a substantial long-term survival in CCgRs is restricted mainly to low-risk and possibly intermediate-risk patients and occurs significantly less often in high-risk patients.

Adult↗