Search PubMed⌕ Search

Biomedical subjects

C Koller

Publications and source records attributed to C Koller.

At least 73 records · Page 4Linked to original sources
PubMed1993

Nucleoside analogs in treatment of chronic lymphocytic leukemia.

The nucleoside analogs fludarabine monophosphate, 2-chlorodeoxyadenosine, and 2-deoxycoformycin (pentostatin) all have activity in chronic lymphocytic leukemia. The most widely studied drug is fludarabine which is able to obtain complete or partial responses in more than 50% of previously treated patients. The response rate is 44% for 2-CDA and approximately 25% for pentostatin. Fludarabine has also been used to treat patients as initial therapy, and has resulted in overall response rate of 79% with 75% of the patients achieving complete remission. The NCI and International Working Group for CLL criteria for complete remission allow for persistent nodules or lymphoid infiltrates in the bone marrow biopsy. Studies have now demonstrated persistent lymphoid aggregates are associated with a shorter time to progression for responders but no survival disadvantage. There is a strong association of documented refractoriness to alkylating agents with probability of response to fludarabine and also survival. The major morbidity associated with the use of these drugs are infections, which, in some circumstances, are associated with neutropenia but in other circumstances are probably related to the hypogammaglobulinemia and T-cell immunodeficiency which are part of the disease. The T-cell immunodeficiency is aggravated by the nucleoside analogs. Even after discontinuation of therapy the immunodeficiency as measured by CD4 cell number is sustained for 12 to 24 months. Opportunistic organisms such as herpes simplex, herpes zoster, Listeria monocytogenes, and pneumocystis carinii are being noted in patients treated with these agents. The potency of these drugs and low incidence of toxicities to other organs suggests that they will be effectively combined with other agents.(ABSTRACT TRUNCATED AT 250 WORDS)

Antineoplastic Agents↗
PubMed1992

Treatment of hairy cell leukemia with 2-chlorodeoxyadenosine (2-CdA).

We administered one course of 2-chlorodeoxyadenosine (2CdA) at 4 mg/m2 daily for 7 days by continuous intravenous infusion to 46 patients with hairy cell leukemia. Complete remissions occurred in 36 patients (78%; 95% confidence limits, 63% to 89%), partial remissions in five (11%), and a minor response in one. One patient died of candida sepsis 3 weeks after beginning treatment and three patients were clearly resistant to therapy. These three either had morphologically atypical hairy cells, less than 20% of which expressed Ig light chain on the cell surface, or had failed prior treatment with deoxycoformycin and interferon-alpha. At a median of 37 weeks since discontinuation of therapy, recurrent thrombocytopenia has developed in one patient, whose marrow remains normal, while a bone marrow relapse has occurred in another patient, whose blood counts remain normal. Treatment produced a greater than 50% decrease in neutrophil count in 26 patients, which lasted 3 to 4 weeks and was associated with an increased incidence of febrile episodes. These episodes occurred in 21 patients but were associated with documented infection in only four patients. Decreases in the number of CD4+ lymphocytes appeared to occur regularly after treatment and have persisted for a median of 18 weeks without obvious clinical significance. Although years of follow-up will be needed, our results confirm Piro et al's observation (N Engl J Med 322: 1117, 1990) that 2CdA appears to be highly effective in the treatment of hairy cell leukemia.

2-Chloroadenosine↗
PubMed1992

Treatment of advanced stages of Philadelphia chromosome-positive chronic myelogenous leukemia with interferon-alpha and low-dose cytarabine.

PURPOSE: To evaluate the efficacy of interferon-alpha (IFN-A) and low-dose cytarabine (ara-C) combination chemotherapy in patients with chronic myelogenous leukemia (CML). PATIENTS AND METHODS: Sixty patients with advanced phases of Philadelphia chromosome (Ph)-positive CML received combination therapy with IFN-A 5 x 10(6) U/m2 daily, and low-dose ara-C 15 mg/m2 daily for 2 weeks every 4 weeks until remission, then for 1 week every month as maintenance. Forty patients were in late chronic-phase CML, and 20 were in accelerated-phase CML (16 with clonal evolution only, four with other criteria). Their outcome was compared with 58 patients (39 late chronic-phase CML and 19 accelerated-phase CML) who had been previously treated with IFN-A alone in the same dose schedule. RESULTS: In late chronic-phase CML, patients receiving IFN-A plus ara-C had a better complete hematologic response (CHR) rate compared with those treated with IFN-A alone (55% v 28%; P = .02), a trend for better Ph suppression (15% v 5%; P = .13), and a longer survival (3-year survival rate 75% v 48%; P less than .01). These differences do not seem to be caused by imbalances in prognostic factors between the two treatment groups. In accelerated-phase CML, the addition of ara-C to IFN-A did not improve the response rate of treated patients, and the difference in survival was accounted for by different patient characteristics. Suppression of clonal evolution was observed in five patients (25%). Patients with clonal evolution as the only criterion for disease acceleration had a longer survival than those with other or additional accelerated-phase criteria (3-year survival rate 67% v 22%; P less than .01). CONCLUSION: The results with the combination of IFN-A plus ara-C in late chronic-phase CML are encouraging, and suggest the need for its evaluation in early chronic-phase CML.

Adult↗
PubMed1991

Mitoxantrone and high-dose etoposide for patients with relapsed or refractory acute leukemia.

Among 35 patients with relapsed or refractory acute myelogenous leukemia (AML) who received salvage chemotherapy, 28 were treated with mitoxantrone (7.5 mg/m2/d intravenously [IV] over 1 hour for 5 days) and etoposide (VP-16) (2 g/m2 over 4 days either as a daily infusion or as two daily doses). Seven patients received mitoxantrone (6 mg/m2/d for 5 days) and VP-16 (1500 mg/m2 over 3 days). The median duration of the initial complete remission (CR) was 6 months and 83% of the patients had initial CR that lasted 12 months or less. Forty-six percent of the patients were undergoing a second or subsequent salvage attempt. Eight patients (23%) achieved CR; seven of these CR were obtained after one course of therapy. Twelve patients (33%) died and 15 patients (42%) had disease that was resistant to treatment. Patients undergoing a first salvage attempt had a higher incidence rate of CR than those undergoing a second or subsequent salvage attempt (37% versus 6%; P = 0.03). CR rates were also higher in patients with a favorable (translocation 8;21 or 15;17) or diploid karyotype compared with other patients (32% versus 8%; P = 0.10). The median survival time was 2 months for all patients and 8 months for patients achieving CR. Mucositis occurred in 74% of the patients and was severe in 32%. Diarrhea and rash occurred in less than 33% of the patients. Fever was noticed in all but 1 of the patients and documented infections occurred in 65% of the patients. Six patients had pancytopenia or thrombocytopenia that lasted more than 42 days from the initiation of treatment. Although mitoxantrone and high-dose VP-16 is an effective antileukemic regimen, it is associated with a high incidence of mucositis. Strategies that are used to limit mucosal damage may improve the tolerance of this combination.

Adult↗
PubMed1991

Comparison of two schedules of cefoperazone plus aztreonam in the treatment of neutropenic patients with fever.

Cancer patients were randomized to receive an every 4 hour or every 8 hour schedule of cefoperazone plus aztreonam during 617 febrile episodes. The overall response rate for the 478 evaluable episodes was 76% and there was no difference in response rate between the two schedules. The response rate was 79% for cases of pneumonia and 63% for cases of bacteremia. Only 50% of the microbiologically documented infections caused by gram-positive organisms responded whereas 95% of gram-negative infections, including all of those caused by Pseudomonas aeruginosa, responded. Response rates were lower among patients whose neutrophil counts decreased during therapy than among those whose neutrophil counts increased (64% vs. 85%, p = 0.008). Side-effects that were possibly or probably related to antibiotic therapy were observed during 11% of the episodes. The most common side-effects were diarrhea and rashes including one case of Stevens-Johnson syndrome. Three patients developed a coagulopathy during therapy. Cefoperazone plus aztreonam proved to be an effective combination for treatment of gram-negative infections and fever of unknown origin in cancer patients and an every 8-hour schedule of administration was as effective as an every 4-hour schedule. Approximately half of the patients with gram-positive infections required additional antibiotics for successful therapy.

Aztreonam↗
PubMed1991

Differential dose-related haematological effects of GM-CSF in pancytopenia: evidence supporting the advantage of low- over high-dose administration in selected patients.

Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a multifunctional haematopoietin which can promote production of several blood cell lineages, though the predominant target cells are neutrophils, monocytes, and their precursors. Occasional undesirable clinical effects include eosinophilia, an increase in blasts, or thrombocytopenia. Here, we describe four patients who were treated with GM-CSF, at subcutaneous doses significantly lower than are conventional, and experienced an unusual response pattern. Three patients had severe pancytopenia associated with chronic lymphocytic leukaemia (CLL) or myelodysplastic syndrome (MDS) and exhibited an unexpected switch in the responsive lineage on high- versus very low-dose therapy. The two CLL patients developed marked eosinophilia (up to 10.0 x 10(9) cells/l) without an increase in neutrophils on 125-300 micrograms/m2/d of GM-CSF. In contrast, when the dose was lowered to 10 micrograms/m2/d, the neutrophils rose to physiological levels, without significant eosinophilia. The MDS patient showed a rapid rise in peripheral blasts (baseline level = 0; post-therapy level = 5.0 x 10(9)/l), without a change in other cell types, when receiving 60 micrograms/m2/d of GM-CSF. After GM-CSF was held, blasts returned to baseline levels; reinstituting therapy at the very low dose of 6 micrograms/m2/d was followed by an increase in platelet counts from 50 to 185 x 10(9)/l with only a minor increase in blasts. The fourth patient, who suffered from severe aplastic anaemia complicated by recurrent gastrointestinal haemorrhage, was only treated with the low-dose regimen. He showed a predominant platelet effect with counts rising from 9 to 169 x 10(9)/l. Very low-dose GM-CSF therapy was devoid of constitutional side effects. The biological implications of these GM-CSF responses are discussed. Our results indicate that, in some patients, GM-CSF may stimulate different target cells depending on the dose. Therefore, in contrast to the results of administration of many classical drugs, there may not always be a direct relationship between the amount of GM-CSF given and the optimal effect.

Adult↗
PubMed1991

Fludarabine: a new agent with marked cytoreductive activity in untreated chronic lymphocytic leukemia.

Thirty-three patients with chronic lymphocytic leukemia (CLL) with advanced Rai stage (III-IV) or progressive Rai stage (0-II) disease were treated with fludarabine as a single agent. Eleven patients (33%) obtained a complete remission (CR), 13 (39%) a clinical CR with residual nodules as the only evidence of disease (nodular partial remission [PR]), and two patients (6%) achieved a PR for a total response rate of 79%. Response was rapid, usually occurring after three to six courses of treatment. The major morbidity was infection. Febrile episodes occurred in 13% of the courses (pneumonia 6%, minor infection 4%, and transient fever of undocumented cause 3%). Fludarabine appears to be the most cytoreductive single agent so far studied in CLL.

Adult↗
PubMed1991

Efficacy of fludarabine, a new adenine nucleoside analogue, in patients with prolymphocytic leukemia and the prolymphocytoid variant of chronic lymphocytic leukemia.

PURPOSE: To describe the results of fludarabine therapy in patients with prolymphocytic leukemia (PLL) and the prolymphocytoid variant of chronic lymphocytic leukemia (CLL-Pro). PATIENTS AND METHODS: Seventeen patients with a diagnosis of PLL or CLL-Pro received fludarabine 30 mg/m2 over 30 minutes daily for 5 days every 4 weeks alone (12 patients), or with prednisone (five patients). Previously defined criteria for response were used. Differences in response rates according to various characteristics were evaluated by chi-square test. RESULTS: Three patients (18%) achieved complete remission, and three (18%) had a partial remission, for an overall response rate of 35%. Responses were durable and occurred in all involved organ sites. Lower response rates were observed in patients with anemia, thrombocytopenia, advanced Rai stages, and primary resistance to prior therapy. Toxicities were minimal except for febrile episodes associated with therapy. CONCLUSION: Fludarabine has shown encouraging results in these patients and deserves further investigation in combination with other active agents, and in the setting of front-line therapy.

Aged↗
PubMed1989

Fludarabine: a new agent with major activity against chronic lymphocytic leukemia.

Fludarabine was used to treat 68 patients with previously treated chronic lymphocytic leukemia (CLL). Nine (13%) patients achieved a complete remission and 30 (44%) a partial remission. The response rates for Rai stages 0 to 2, 3, and 4 were 64%, 58%, and 50% respectively. Seventeen (43%) of the 40 Rai stage 1 to 3 patients and four (19%) of the Rai stage 4 patients returned to Rai stage 0. Survival was strongly correlated with the final Rai stage achieved. The survival of the 11 partial responders with residual disease consisting only of residual bone-marrow nodules was similar to the complete responders (36+ months) and superior to the other partial response patients (16 months). The response to fludarabine was rapid, with 36 (92%) of the 39 responders having achieved at least a partial response following the first three courses. Complete responses occurred in the blood, liver, spleen, and lymph nodes in 48% to 69% of the patients. Eradication of all disease in the bone marrow occurred in only 13% of the cases. Neutropenia and thrombocytopenia occurred in 56% and 25% of evaluable courses. Major infections occurred in 9% of evaluable courses and fevers of unknown origin or minor infections in 12% of courses respectively. Myelosuppression and infection were more common in patients with initial Rai stages 3 and 4 and in nonresponding patients. Other toxicity was mild. No CNS toxicity was noted.

Antimetabolites, Antineoplastic↗
PubMed1988

Detection of leukemic clone maturation in vivo by premature chromosome condensation.

The purpose of this study was to determine the feasibility of using the technique of premature chromosome condensation to detect the in vivo maturation of abnormal elements in patients with chronic myelogenous leukemia (CML), myelodysplastic syndrome, and acute leukemia. Patients were chosen for study if there were a clinical suggestion of in vivo maturation and a leukemic clone exhibiting a distinguishable karyotypic abnormality. Mature peripheral blood granulocytes were enriched by two-step Ficoll-Hypaque gradient sedimentation and fused with mitotic Chinese hamster ovary cells to induce the formation of prematurely condensed chromosomes (PCC). These PCC were then analyzed for chromosome number per cell (in the case of patients with a numerical abnormality) or by G-banding (in the case of specific translocations). Of 13 patients chosen for study, 12 showed karyotypic evidence for maturation of the abnormal elements in vivo. Maturation was observed in a number of clinical situations including before treatment in benign CML and myelodysplasia, after low-dose and high-dose chemotherapy in myelodysplasia and acute myelogenous leukemia (AML), and in remission. These results suggest that the technique of premature chromosome condensation can be a powerful tool in better understanding the biology of disease and mode of response to therapy in vivo in patients with leukemia and preleukemic syndromes, especially during treatment with agents thought to induce maturation of the leukemic elements.

Aneuploidy↗
PubMed1987

Granulocytic sarcoma presenting as pulmonary nodules and lymphadenopathy.

A patient presented with anterior and posterior cervical lymphadenopathy as well as widespread intrapulmonary nodules. Histologic sections of both lymph node and lung revealed dense infiltration by sheets of cells which were cytochemically positive for chloroacetate esterase and myeloperoxidase, thus suggesting a diagnosis of granulocytic sarcoma. The patient was initially treated with daily hydroxyurea. After 6 weeks, when progression of the disease was apparent, hydroxyurea was discontinued and the patient was placed on mithramycin, an agent reported to induce differentiation of myeloid precursor cells both in vitro and in vivo. On this latter agent, a dramatic response has been noted with a decrease in the pulmonary symptoms, and a marked reduction in the size of the lymph nodes and lung nodules. The authors report this case because it represents a rare presentation of an uncommon disease and because of the striking improvement that followed the initiation of a novel therapeutic modality.

Aged↗
PubMed1987

Thyrotropin (TSH) stimulates cell growth and DNA synthesis in monolayer cultures of human thyrocytes independent of the adenylate-cyclase system.

Monolayer cultures of human thyrocytes from normal thyroids (n = 13), thyroid adenomas (n = 8), differentiated (n = 7), poorly and undifferentiated (n = 5) thyroid cancers as well as thyroid cancer metastases (n = 2) were established to assess the significance of TSH and cAMP on cell growth and DNA synthesis. Cell growth was stimulated by 0.1 IU bTSH/ml and inhibited by 1.0 IU bTSH/ml (P less than 0.01), while dibutyryl-cAMP (dbcAMP) failed to show any effect on cell growth at the concentrations (10-5; 10-3 mol/l), tested. Neither did the adenylate-cyclase inhibitor dideoxy-adenosine (ddA) (2 X 10-5 mol/l) stimulate thyrocyte growth. DNA synthesis, however, measured indirectly by [3H]thymidine incorporation, was stimulated not only by TSH 2-12-fold, but also by ddA 1.3-7-fold (P less than 0.01), and was not affected by dbcAMP. TSH had no effect on [3H]thymidine incorporation in fibroblasts and c-cells from c-cell carcinomas. The stimulatory effect of TSH on thyrocyte growth and DNA synthesis was unpredictable in thyrocytes from cancerous tissues (n = 14) with no obvious correlation to tumour differentiation or stage. Thus, we showed that TSH is a promotor for cell growth and DNA synthesis in monolayer cultures of human thyrocytes from normal and adenomatous human thyroid tissues with no obvious correlation to the AC system. This TSH effect is unpredictable, however, in thyrocytes from human thyroid cancer.

Adenoma↗
PubMed1987

Adenylate cyclase stimulation and [3H]thymidine incorporation in human thyroid tissues and thyrocyte cultures: the effect of IgG preparation from patients with different thyroid disorders.

Primary cell cultures of normal and adenomatous human thyroid tissues were incubated with TSH or ammonium sulphate precipited IGG fractions (1 mg/ml) of sera from patients with different thyroid diseases (Graves' disease: active n = 7 in remission n = 12; thyroid autonomy n = 39; simple euthyroid goitre n = 15) and were compared to controls (n = 26). [3H]thymidine incorporation in primary thyrocyte cultures demonstrated a typical bell shape curve after incubation with EGF and TSH with a maximal effect at 10-100 microIU/ml. This effect, however, was inconsistent and positive only in 2 of 7 primary cultures. Only TSH positive cultures were used for IgG studies. 16-28% of IGG fractions from sera of thyroid patients caused high (more than X + 5 SD of controls) stimulation of [3H]thymidine incorporation. Dose response curves of IgG fractions of 19 additional patients (Graves' disease in remission n = 15; thyroid autonomy n = 4) showed an increase in [3H]thymidine incorporation at 0.1 mg protein/ml for 10 patients and at low concentrations of 10-5 mg/ml for 5 patients. There was a good correlation (r = 0.72) (P less than 0.0001) between positive findings in TSH-binding inhibition (TBII) and AC-stimulation (TSI) IGG fractions but none between stimulation of [3H]thymidine incorporation and any other thyroid specific immunoglobulin nor thyroid function nor any other available data. Immunoglobulins stimulating [3H]thymidine incorporation differ therefore from TBII and TSI. The growth effect of these immunoglobulins, however, has yet to be determined.

Adenoma↗
PubMed1987

Nerve growth factor (NGF) sensitizes human medullary thyroid carcinoma (hMTC) cells for cytostatic therapy in vitro.

Medullary thyroid carcinoma (hMTC) cells were established from nine patients with MTC disease to initiate a new approach of adjuvant medical therapy in these patients. We measured calcitonin (CT) secretion, DNA synthesis, and cell proliferation in vitro and their response to various substances. Nerve growth factor (NGF) (0.01 to 10 micrograms/ml), glucagon (0.01 to 100 micrograms/ml), and isoproterenol (4 to 500 micrograms/ml) stimulated CT secretion and DNA synthesis in hMTC cells. Other substances, calcium (1.0 to 15 mmol), pentagastrin (1.0 to 50 mumol), dibutyryl-cyclic-adenosine-monophosphate (1.0 to 100 mumol), and phorbol ester TPA (1.0 to 100 nmol), stimulated CT secretion but not DNA synthesis. In addition, NGF enhanced cell proliferation of hMTC cells 2- to 3- fold and caused an increased sensitivity of these cells for chemotherapy in vitro. Thus 0.5 microgram/ml doxorubicin (half-maximal effective dose) induced a cell death rate of up to 32.8%, which was enhanced by preincubation with NGF to 68.1% (1.0 microgram/ml, NGF) and to 100% (10.0 micrograms/ml, NGF), respectively. Pulsative stimulation of APUD cell carcinomas with NGF may therefore improve the response rate of these tumors to chemotherapy, which would be of significant clinical importance for patients with residual postoperative MTC tissue.

Antineoplastic Agents↗