Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 30
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
2.
Bone Marrow Transplant ; 42(7): 475-81, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18622420

RESUMO

Neutropenia following high-dose chemotherapy leads to a high incidence of infectious complications, of which central venous catheter-related infections predominate. Catheter-related infections and associated risk factors in 392 patients participating in a randomized adjuvant breast cancer trial and assigned to receive high-dose chemotherapy and peripheral stem-cell reinfusion were evaluated. Median catheter dwell time was 25 days (range 1-141). Catheter-related infections were seen in 28.3% of patients (11 infections per 1000 catheter-days). Coagulase-negative staphylococci were found in 104 of 186 positive blood cultures (56%). No systemic fungal infections occurred. Cox regression analysis showed that duration of neutropenia >10 days (P=0.04), using the catheter for both stem-cell apheresis and high-dose chemotherapy (P= <0.01), and use of total parenteral nutrition (TPN, P=0.04) were predictive for catheter-related infections. In conclusion, a high incidence of catheter-related infections after high-dose chemotherapy was seen related to duration of neutropenia, use of the catheter for both stem-cell apheresis and high-dose chemotherapy, and use of TPN. Selective use and choice of catheters could lead to a substantial reduction of catheter-related infectious complications.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Cateterismo/efeitos adversos , Cateteres de Demora/efeitos adversos , Terapia Combinada/efeitos adversos , Infecções/etiologia , Nutrição Parenteral Total/efeitos adversos , Transplante de Células-Tronco de Sangue Periférico/efeitos adversos , Antineoplásicos/administração & dosagem , Neoplasias da Mama/complicações , Neoplasias da Mama/cirurgia , Feminino , Humanos , Infecções/epidemiologia , Países Baixos , Neutropenia/etiologia , Valor Preditivo dos Testes , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Tempo
3.
Br J Cancer ; 95(10): 1334-41, 2006 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-17088909

RESUMO

Benefit from chemotherapy treatment in breast cancer patients is determined by the molecular make-up of the tumour. In a retrospective analysis, we determined the molecular subtypes of breast cancer originally defined by expression microarrays by immunohistochemistry in tumours of patients who took part in a randomised study of adjuvant high-dose chemotherapy in breast cancer. In addition, the topoisomerase II alpha (TOP2A) amplification status was determined by fluorescence in situ hybridisation and chromogenic in situ hybridisation. 411 of the 753 tumours (55%) were classified as luminal-like, 137 (18%) as basal-like and 205 (27%) as human epithelial receptor type 2 (HER2) amplified. The basal-like tumours were defined as having no expression of ER and HER2; 98 of them did express epidermal growth factor receptor and/or cytokeratin 5/6. The luminal-like tumours had a significantly better recurrence free and overall survival than the other two groups. From the 194 HER2-positive tumours, 47 (24%) were shown to harbour an amplification of TOP2A. Patients with an HER2-amplified tumour randomised to the high-dose therapy arm did worse than those in the conventional treatment arm, possibly caused by the lower cumulative anthracycline dose in the high-dose arm. The tumours with a TOP2A amplification contributed hardly to this difference, suggesting that TOP2A amplification is not the cause of the steep dose-response curve for anthracyclines in breast cancer. Possibly, the difference of the cumulative dose of only 25% between the treatment arms was insufficient to yield a survival difference.


Assuntos
Antígenos de Neoplasias/genética , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/terapia , DNA Topoisomerases Tipo II/genética , Proteínas de Ligação a DNA/genética , Amplificação de Genes , Recidiva Local de Neoplasia/enzimologia , Recidiva Local de Neoplasia/terapia , Adulto , Antraciclinas/administração & dosagem , Biomarcadores Tumorais/genética , Neoplasias da Mama/classificação , Neoplasias da Mama/enzimologia , Carboplatina/administração & dosagem , Quimioterapia Adjuvante , Ciclofosfamida/administração & dosagem , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Hibridização In Situ , Metástase Linfática , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/genética , Países Baixos , Transplante de Células-Tronco de Sangue Periférico , Proteínas de Ligação a Poli-ADP-Ribose , Prognóstico , Receptor ErbB-2/genética , Tiotepa/administração & dosagem , Resultado do Tratamento
4.
Ann Oncol ; 17(4): 588-96, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16446318

RESUMO

BACKGROUND: High-dose chemotherapy in the adjuvant treatment of breast cancer has been abandoned by many. PATIENTS AND METHODS: 885 patients with stage III primary breast cancer and four or more axillary lymph node metastases were randomised to receive either five courses of FEC (fluorouracil, epirubicin and cyclophosphamide) followed by radiation therapy and tamoxifen, or the same treatment but with high-dose alkylating chemotherapy (cyclophosphamide, thiotepa and carboplatin) replacing the fifth course of FEC. Of these patients, 621 had HER2/neu-negative disease, as determined by immunohistochemistry and chromogenic in situ hybridisation. RESULTS: At a median follow-up of 84 months, a trend for a better relapse-free survival was observed in the high-dose arm: (hazard ratio (HR) 0.84, P = 0.076, two-sided). The 621 patients with HER2/neu-negative disease benefited from high-dose therapy, while patients with HER2/neu-positive disease did not (test for interaction, P = 0.006). There was a marked relapse-free survival benefit for patients with HER2/neu-negative disease (71.5% versus 59.1%, 5 years after randomisation; HR 0.68, P = 0.002) and also a survival benefit (78.2% versus 71.0% at 5 years; HR 0.72, P = 0.02). CONCLUSIONS: The findings from this subgroup analysis provide additional evidence that HER2/neu-positive breast cancer is relatively resistant to alkylating agents. For HER2/neu-negative tumours, however, high-dose chemotherapy should remain the subject of clinical studies.


Assuntos
Antineoplásicos Alquilantes/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Genes erbB-2 , Antineoplásicos Alquilantes/efeitos adversos , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Relação Dose-Resposta a Droga , Feminino , Humanos , Imuno-Histoquímica , Segunda Neoplasia Primária/induzido quimicamente , Estudos Prospectivos , Análise de Sobrevida
5.
Eur J Cancer ; 38(4): 556-9, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11872349

RESUMO

Gemcitabine (2'-deoxy-2'-difluorocytidine monohydrochloride) at a dose of 1250 mg/m(2) was given as a 30-min intravenous (i.v.) infusion on days 1 and 8 in a 3-weekly schedule to 32 patients with advanced soft-tissue sarcoma (STS) failing first-line chemotherapy. One patient was ineligible due to a delay between the previous chemotherapy and the start of treatment. Of the eligible patients, median age was 53 years (range 23-73 years). The predominant histological subtype was leiomyosarcoma in 12 patients (38%). The median number of cycles was three (range 1-8 cycles) with a median total dose of gemcitabine of 6.25 g/m(2) (range 1.25-19.97 g/m(2)). The relative dose intensity of gemcitabine was 96% (range 50-103%). Treatment was tolerated very well with non-complicated haematological toxicity as the most frequently observed side-effect. Only one partial tumour response was documented, giving a response rate of 3.23% (95% Confidence Interval (CI): 0.08-16.2%). The median overall survival was 268 days (95% CI: 129-377) and the median time to progression was 45 days (95% CI: 41-79). These results indicate that gemcitabine given at this dose and schedule is not active as second-line therapy in advanced STS.


Assuntos
Antimetabólitos Antineoplásicos/administração & dosagem , Desoxicitidina/análogos & derivados , Desoxicitidina/administração & dosagem , Sarcoma/tratamento farmacológico , Adulto , Idoso , Antimetabólitos Antineoplásicos/efeitos adversos , Desoxicitidina/efeitos adversos , Feminino , Seguimentos , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Sarcoma/patologia , Análise de Sobrevida , Gencitabina
6.
J Surg Oncol ; 72(3): 124-9, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10562357

RESUMO

BACKGROUND AND OBJECTIVES: The oncologic and functional results in patients treated because of osteosarcoma (OS) were evaluated. METHODS: Fifty-one patients with high-grade OS were treated between 1974 and 1996 at our hospital. All patient records were studied, and the surviving patients were evaluated according to the American Musculoskeletal Tumor Society functional rating system. The majority of patients received adjuvant chemotherapy (prior to 1983) or neoadjuvant chemotherapy (from 1983). Until 1987, all patients with extremity OS had ablative surgery; from 1987, the majority had limb-saving surgery. Lung metastases were resected in most cases. RESULTS: Overall 2-year and 5-year disease-free survival (DFS) rates were 27 of 51 and 16 of 42, respectively. Patients with vertebral or pelvic OS or contaminated margins after resection had a very bad outcome. In all other subgroups, including patients with various types of chemotherapy, response to chemotherapy, diameter of tumor, presence or absence of metastatic spread, and location of tumor, a 5-year DFS of about 50% was found. Recurrent disease in patients who had achieved a 2-year disease-free interval was relatively low (4/23 patients). CONCLUSIONS: Survival in our series was worse than in most other studies. A very bad outcome was found in patients with vertebral or pelvic OS or with contaminated margins after resection.


Assuntos
Neoplasias Ósseas/mortalidade , Osteossarcoma/mortalidade , Adolescente , Adulto , Idoso , Neoplasias Ósseas/fisiopatologia , Neoplasias Ósseas/terapia , Criança , Pré-Escolar , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Osteossarcoma/fisiopatologia , Osteossarcoma/terapia
8.
Eur J Surg Oncol ; 24(2): 114-9, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9591026

RESUMO

AIM: To evaluate the oncological and functional result of the treatment of patients with a synovial sarcoma. This paper gives a retrospective review of 20 patients (15 male and five female) treated for synovial sarcoma at the Nijmegen University Hospital, The Netherlands. METHODS: The median age of the patients was 30 years (range: 14-71, mean 37 years). RESULTS: The tumour locations were: lower extremity in 12 patients; upper extremity in three; pelvic and groin region in four; and the retroperitoneal space in one. Surgical stages according to Enneking (Clin Orthop 1986; 204: 9-24) were IIA in five cases; IIB in seven; and IIIB in eight. The surgical margin was intralesional in three cases; marginal in three; wide in six; and radical in six. In one case the surgical margin could not be assessed and one patient was not operated. One patient developed a recurrent tumour and one developed nodal metastases. Eight patients who did not have metastases at the time of diagnosis developed metastase during follow-up. Fourteen patients died of metastatic disease; one patient died of diabetes; one is alive with disease; and four presently do not have evidence of disease. CONCLUSIONS: The outcome was poor, especially due to the occurrence of pulmonary metastases. The functional result according to the MSTS was 100% in four patients; in one the result was 93% because of the scar and venous insufficiency.


Assuntos
Sarcoma Sinovial/patologia , Sarcoma Sinovial/fisiopatologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Sarcoma Sinovial/cirurgia , Análise de Sobrevida , Resultado do Tratamento
9.
Br J Cancer ; 74(7): 1023-9, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8855969

RESUMO

This paper deals with the utility of immunoliposomes for the delivery of doxorubicin (DXR) to human ovarian carcinoma cells in vitro and in vivo. We aimed to investigate whether immunoliposome-mediated targeting of DXR to ovarian cancer cells translates in an enhanced anti-tumour effect compared with that of non-targeted DXR liposomes (lacking the specific antibody). Target cell binding and anti-tumour activity of DXR immunoliposomes were studied in vitro and in vivo (xenograft model of ovarian carcinoma). In vitro we observed that target cell binding and cell growth inhibition of DXR immunoliposomes is superior to that of non-targeted DXR-liposomes. However, in vivo, despite the efficient target cell binding and good anti-tumour response of DXR-immunoliposomes, no difference in anti-tumour effect, compared with non-targeted DXR-liposomes, could be determined. The results indicate that premature DXR leakage from immunoliposomes occurring before the actual target cell binding and subsequent DXR association with the tumour cells, explains why no significant differences in anti-tumour activity between DXR-immunoliposomes and non-targeted DXR-liposomes were observed in vivo.


Assuntos
Antibióticos Antineoplásicos/uso terapêutico , Doxorrubicina/uso terapêutico , Neoplasias Ovarianas/tratamento farmacológico , Animais , Antibióticos Antineoplásicos/administração & dosagem , Antibióticos Antineoplásicos/metabolismo , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/uso terapêutico , Divisão Celular/efeitos dos fármacos , Doxorrubicina/administração & dosagem , Doxorrubicina/metabolismo , Portadores de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Lipossomos/metabolismo , Camundongos , Camundongos Nus , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Células Tumorais Cultivadas
14.
Ann Oncol ; 5(6): 539-42, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7918126

RESUMO

BACKGROUND: Current regimens for treatment of distant metastases of soft tissues sarcomas result in response rates of about 25%. Therefore the search for active drugs remains a task for investigational groups. Taxoids offer a new class of cytostatic drugs. Docetaxel has been studied as a second line chemotherapy in advanced soft tissue sarcomas of the adult. PATIENTS AND METHODS: In a multi-center non-randomized phase II study docetaxel was administered at a dose of 100 mg/m2 in a 1-hour i.v. infusion q 3 weeks. RESULTS: Twenty-nine patients (pts), median age 52 yr, performance status WHO 0: 16 pts, WHO 1: 11 pts, WHO 2: 2 pts, were eligible. One patient had early death due to malignant disease, 1 patient died due to toxicity and progression, 1 pt refused after 1 course. Five partial responses (5/29 = 17%, C.I. 6%-36%) have been observed. Grade > or = 3 leucopenia occurred in 76% of patients and grade > or = 3 thrombopenia did not occur. Median nadir of neutrophils was 0.23 x 10(9)/l. Episodes of fever and documented infection have been observed in 10 and 5 pts respectively. Anaphylactoid type reactions occurred in 5 patients: ranging from flushing in 5 pts to cardiovascular symptoms in 1 pt. Sensory neurotoxicity was observed in 14 pts grade 1: 10 pts, grade 2: 3 pts, grade 3: 1 pt). Grade 1 motor neurotoxicity was experienced by 3 pts. Skin reactions (pruritus, erythema, urticaria, exfoliation grade 1: 11 pts, grade 2: 7 pts, grade 3: 1 pt, grade 4: 1 pt) in 20 pts, among them 9 patients with nail changes. Peripheral edema and fluid retention has been observed in 12 pts. CONCLUSION: Taxotere has activity in adult soft tissue sarcoma in second line, warranting studies on first line efficacy.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Paclitaxel/análogos & derivados , Sarcoma/tratamento farmacológico , Neoplasias de Tecidos Moles/tratamento farmacológico , Taxoides , Adulto , Idoso , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/efeitos adversos , Docetaxel , Esquema de Medicação , Europa (Continente) , Feminino , Humanos , Leucopenia/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/induzido quimicamente , Paclitaxel/administração & dosagem , Paclitaxel/efeitos adversos , Paclitaxel/uso terapêutico , Indução de Remissão , Trombocitopenia/induzido quimicamente
15.
Eur J Cancer ; 28(2-3): 686-90, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1591094

RESUMO

Toxicity and results of two different dose levels of chemotherapy with cyclophosphamide, methotrexate and 5-fluorouracil (CMF) in older (greater than 70 years) patients with advanced breast cancer were evaluated in a prospective (non-randomised) study. During the first three courses of chemotherapy dose reduction for haematological toxicity was necessary in all of 10 and 8 of 13 patients treated with an intended dose of 100% and 75% of standard dose CMF, respectively. The median percentages of CMF, administered during the first three courses were about 75% in both groups of patients corresponding with a median dose intensity of 72% (range 49-87%) and 64% (range 36-78%) for patients of the 100% and 75% dose group, respectively. In 34 younger postmenopausal women (mean age 57 years) treated in our institution for advanced breast cancer the median percentages of CMF in the second and third course were 86% and 84%, respectively with a median dose intensity during the three courses of 82%. Dose reductions of CMF and bone marrow toxicity, though interdependent, were statistically significantly correlated with the endogenous creatinine clearance, but not with age. 1 patient died during severe leukopenia and thrombocytopenia. Non-haematological side effects were most pronounced in the 100% group. Results of therapy in both groups of patients were about equal and compared well with those of CMF therapy in general. It is advised that the dose of CMF in patients above 70 years should not exceed 75% of standard dose. Further dose reduction of methotrexate in case of severe renal failure is required.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/metabolismo , Creatinina/metabolismo , Ciclofosfamida/administração & dosagem , Ciclofosfamida/efeitos adversos , Esquema de Medicação , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Doenças Hematológicas/induzido quimicamente , Humanos , Metotrexato/administração & dosagem , Metotrexato/efeitos adversos
17.
NMR Biomed ; 4(1): 16-24, 1991 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2029456

RESUMO

Adriamycin induced cardiotoxicity is, among other factors, characterized by an impairment of mitochondrial function and altered energy metabolism. The possible merits of 31P NMR in timely detection of this cardiotoxicity were studied in perfused hearts of chronically treated rats after cumulative doses of 6, 8, 10, 12 and 13 mg adriamycin/kg body wt and compared to histological evaluation. After high cumulative doses the Phosphocreatine (PCr)/ATP ratio was significantly decreased in the hearts of treated animals, compared to the control animals (1.65 +/- 0.13 vs. 2.47 +/- 0.36 (p less than 0.001) at 12 mg/kg and 1.92 +/- 0.22 vs. 2.37 +/- 0.15 (p less than 0.01) at 13 mg/kg adriamycin, respectively). This decrease coincides with a sudden increase in the histological score from 2.0 at 10 mg/kg to 8.0 at 12 mg/kg adriamycin on a scale of 10.0. The Pi/PCr ratio, coronary flow and rate pressure product (RPP) of the isolated hearts of treated animals were not significantly different from controls. When heart rates were increased, parallel changes in PCr/ATP ratio, Pi/PCr ratio, RPP and coronary flow were observed in both control and treated groups, except for the 12 mg/kg adriamycin group in which pacing failed to increase RPP. In addition, in this group the Pi/PCr ratio at higher heart rates was significantly increased (p less than 0.001) compared to controls. At 13 mg/kg similar effects were observed but less pronounced. The decreased PCr/ATP ratio may indicate an increased ADP concentration and altered regulation of energy metabolism. Differences between control and treated groups in RPP and Pi/PCr ratio during pacing may also be related to cardiotoxicity.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Trifosfato de Adenosina/análise , Doxorrubicina/toxicidade , Coração/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Fosfocreatina/análise , Animais , Masculino , Miocárdio/química , Miocárdio/patologia , Tamanho do Órgão/efeitos dos fármacos , Ratos
18.
Lung ; 168 Suppl: 1069-74, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2117107

RESUMO

The concept of immunotherapy is evolving from nonspecific, haphazard stimulation of the immune apparatus to more specific and controlled manipulation of the immune system. IL-2 gives the opportunity to exert influence on the cellular immune system. Why LAK cells are able to lyse tumor cells and leave normal cells intact is not known. How LAK cells behave after reinfusion is not known; are they able to migrate to tumor sites? Can improvements be made in scheduling in order to decrease toxicity and to enhance efficacy? But first of all, the question arises whether the tremendous efforts required by adoptive transfer, in terms of toxicity, logistics, and money, are outweighed by the therapeutic results. For clinical practice inside the frontier of oncology, continuous infusion of IL-2 at an intermediate dose is a quite attractive option in finding a balance between efforts and results.


Assuntos
Interleucina-2/uso terapêutico , Neoplasias/terapia , Animais , Citotoxicidade Imunológica/efeitos dos fármacos , Humanos , Imunização Passiva/métodos , Células Matadoras Ativadas por Linfocina/imunologia , Células Matadoras Ativadas por Linfocina/transplante , Neoplasias/imunologia
19.
Cancer Chemother Pharmacol ; 25(2): 131-4, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2598399

RESUMO

A total of 19 patients (7 men, 12 women) with locally advanced pancreatic adenocarcinoma were treated with six cycles of FAP (5-fluorouracil, 300 mg/m2 i.v. on days 1-5; Adriamycin, 50 mg/m2 i.v. on day 1; cisplatin, 20 mg/m2 i.v. on days 1-5). Each course was repeated every 28 days. After six cycles, the treatment was followed by irradiation amounting to 4,000 cGy (split course) in combination with 5-FU (500 mg/m2) on days 1-3 of the two irradiation periods. The median age of our patients was 55 years (range, 40-64 years). The median WHO performance status was 1, with a range of 0-2. Three (16%) complete (CR) and six (31%) partial responses (PR) were observed, as were six cases of stable disease (SD) and four of progressive disease (PD). The median duration of response was 11 months, with a range of 4-24 months, and the median survival was 14 months (range, 5-27 + months). FAP toxicity was tolerated fairly poorly. The dose-limiting toxic effect was myelosuppression, with a mean WBC nadir of WHO grade 1.6 (range, 0-3) and a mean platelet count of WHO grade 1.1 (range, 0-4). Nausea and vomiting were not dose-limiting. Complete alopecia was seen in 14/19 patients. Neuropathy was mild (WHO grade 1) in seven and moderate (grade 2) in four. Irradiation in combination with 5-FU was generally well tolerated. Due to several reasons, only ten patients could be treated with all six cycles of FAP. We conclude that in future combined modality studies, irradiation should be given after three cycles of chemotherapy, and that combined modality treatment for locally advanced pancreatic cancer is feasible and warrants further testing.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/radioterapia , Adulto , Cisplatino/administração & dosagem , Terapia Combinada , Doxorrubicina/administração & dosagem , Avaliação de Medicamentos , Feminino , Fluoruracila/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/mortalidade , Dosagem Radioterapêutica , Indução de Remissão , Fatores de Tempo
20.
Cancer Chemother Pharmacol ; 24(6): 341-8, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2791187

RESUMO

Liposome encapsulation of doxorubicin (DXR) has been shown to increase the therapeutic index of the drug in several animal systems. The prevention of peak plasma concentrations of free drug might be a major factor contributing to the beneficial effects resulting from liposome encapsulation. If so, the administration of DXR as a continuous infusion should also lead to an improved therapeutic index. In the present paper, the administration of liposome-encapsulated DXR is compared with the infusion of DXR with regard to their potential to preserve antitumor activity, enhance survival and reduce cardiomyo- and nephropathy in IgM immunocytoma-bearing Lou/M Wsl rats. Plasma concentrations of DXR were determined to correlate the biological results with pharmacokinetic parameters. Liposomes containing phosphatidylcholine, phosphatidylserine and cholesterol (extrusion-multilamellar vesicles) were used. Bolus injections of free DXR (free DXR) and DXR liposomes (lip-DXR) in a multiple-dose regimen were compared with 24-h infusions of the same cumulative doses of DXR (inf-DXR). The antitumor activity of inf-DXR equalled that of free DXR as well as that of lip-DXR at doses of greater than 0.25 mg/kg. The overall survival of tumor-bearing animals treated with 2.0 mg/kg lip-DXR was significantly prolonged (P less than 0.01) in comparison with that of animals treated with 2.0 mg/kg free DXR; however, treatment with 2.0 mg/kg inf-DXR did not induce a significant prolongation of survival. At a cumulative dose of 12 mg/kg, inf-DXR appeared to be as effective as lip-DXR in reducing the severity of cardiomyopathy induced by free DXR. However, for the reduction of nephropathy, only therapy with lip-DXR was effective. Inf-DXR induced high nephropathy scores comparable with those obtained with free DXR. For the first 24 h after an injection of 2.0 mg/kg or after the start of a continuous infusion of 2.0 mg/kg given over 24 h, similar areas under the plasma concentration-time curves (AUC) were calculated for free DXR and inf-DXR. However, for lip-DXR a much higher value was calculated. The higher plasma levels of lip-DXR did not result in higher cardiac levels. After five daily doses of 2.0 mg/kg, a much lower DXR concentration was found in cardiac tissue after the administration of lip-DXR than after the administration of free DXR or inf-DXR. This suggests that an important parameter to be determined and correlated with biological results is the free (i.e. not bound to liposomes) circulating fraction of DXR in lip-DXR-injected animals.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Doxorrubicina/administração & dosagem , Cardiopatias/induzido quimicamente , Nefropatias/induzido quimicamente , Animais , Peso Corporal/efeitos dos fármacos , Relação Dose-Resposta a Droga , Doxorrubicina/sangue , Doxorrubicina/toxicidade , Portadores de Fármacos , Infusões Intravenosas , Injeções Intravenosas , Lipossomos , Masculino , Neoplasias Experimentais/tratamento farmacológico , Ratos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...