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1.
Eur Spine J ; 15(4): 472-8, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15937675

RESUMO

This study was conducted to study the functional outcome after non-operative treatment of type A thoracolumbar spinal fractures without neurological deficit. Functional outcome was determined following the International Classification of Functioning, Disability and Health, measuring restrictions in body function and structure, restrictions in activities, and restrictions in participation/quality of life. All patients were treated non-operatively for a type A thoracolumbar (Th11-L4) spinal fracture at the University Hospital Groningen, The Netherlands. Thirty-three of the eighty-one selected patients agreed to participate in the study (response-rate 41%). Respondents were older than non-respondents (mean 50.5 years vs. 39.2 years), but did not differ from each other concerning injury-related variables. Patients with a neurological deficit were excluded. Treatment consisted either of mobilisation without brace, or of bedrest followed by wearing a brace. Restrictions in body function and structure were measured by physical tests (dynamic lifting test and bicycle ergometry test); restrictions in activities were measured by means of questionnaires, the Roland Morris Disability Questionnaire (RMDQ) and Visual Analogue Scale Spine Score (VAS). Restrictions in participation/quality of life were assessed with the Short Form 36 (SF-36) and by means of return to work status. Thirty-seven per cent of the patients were not able to perform the dynamic lifting test within normal range. In the ergometry test, 40.9% of the patients performed below the lowest normal value, 36.4% of the patients achieved a high VO(2)-max. Mean RMDQ-score was 5.2, the mean VAS-score was 79. No significant differences between patients and healthy subjects were found in SF-36 scores, neither were differences found between braced and unbraced patients in any of the outcome measures. Concerning the return to work status, 10% of the subjects had stopped working and received social security benefits, 24% had arranged changes in their work and 14% had changed their job. We conclude that patients do reasonably well 5 years after non-operative treatment of a thoracolumbar fracture, although outcome is diverse in the different categories and physical functioning seems restricted in a considerable number of patients.


Assuntos
Vértebras Lombares/lesões , Fraturas da Coluna Vertebral/terapia , Vértebras Torácicas/lesões , Adulto , Idoso , Repouso em Cama , Braquetes , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Recuperação de Função Fisiológica , Resultado do Tratamento
2.
Neth J Med ; 61(7): 249-56, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-14567522

RESUMO

BACKGROUND: Irinotecan is an effective treatment for metastatic colorectal cancer. However, its use may be associated with troublesome adverse effects such as delayed diarrhoea, acute cholinergic syndrome and neutropenic infection. The manufacturer decided to release irinotecan for compassionate use in The Netherlands prior to its regulatory approval (June 1998) and first introduction for second-line treatment of metastatic colorectal cancer. In view of the drug's adverse effect profile this was done in a carefully controlled manner. METHODS: Irinotecan was made available to patients with colorectal cancer with elaborate precautions. Treating physicians requesting irinotecan for compassionate use received a protocol, providing recommendations for the proper use and the prevention/management of potentially troublesome adverse events. Limited demographic, toxicity and efficacy data were collected. RESULTS: Between June 1997 and September 1998, 112 patients were registered for this programme, 103 of whom actually received irinotecan. The percentage of patients experiencing grade 3-4 adverse effects was relatively low: delayed diarrhoea in 17%, nausea and vomiting 17%, acute cholinergic syndrome 6%, febrile neutropenia 4% and neutropenic infection 2%. Five partial tumour responses and a high proportion of patients with 'no change' were noted. CONCLUSIONS: The carefully controlled release of irinotecan for compassionate use with a very detailed protocol for guidance and advice on safety precautions seems to have contributed to the relatively safe use of the drug outside the setting of a formal clinical trial.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Camptotecina/análogos & derivados , Camptotecina/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Adulto , Idoso , Antineoplásicos Fitogênicos/efeitos adversos , Camptotecina/efeitos adversos , Aprovação de Drogas , Feminino , Seguimentos , Humanos , Irinotecano , Masculino , Pessoa de Meia-Idade , Países Baixos , Avaliação de Programas e Projetos de Saúde , Resultado do Tratamento
3.
Eur Spine J ; 12(3): 261-7, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12800001

RESUMO

The aim of the study was to develop an insight into the impairments in spinal fracture patients, operatively treated with an internal fixator, and also into their ability to participate in daily living, return to work and quality of life as defined by the World Health Organization. Nineteen patients operated for a type A fracture of the thoracolumbar spine (T9-L4) between 1993 and 1998 in the University Hospital Groningen, the Netherlands, aged between 18 and 60 years, without neurological deficit were included in the study. Operative treatment consisted of fracture reduction and internal fixation using the Universal Spine System, combined with transpedicular cancellous bone grafting and dorsal spondylodesis. No ventral fusion operations, laminectomies or discectomies were done. Restrictions in body function and structure were measured on radiographs and in functional capacity tests, such as lifting tests and ergometry. Restrictions in activities were studied with the Visual Analogue Scale (VAS) Spine Score and the Roland Morris Disability Questionnaire (RMDQ). Restrictions in participation/quality of life were analysed with the Short Form 36 (SF36) and described in the return to work status. The radiological results are comparable to the literature. The reduction of the anterior wedge angle was followed by a gradual partial loss of intervertebral angle and regional angle. The maximum oxygen uptake (VO2-max) was reduced in only 8.3% of the patients. Arm and trunk lift was within the normal range in 87% and 80% of the patients respectively, but only 53% of the patients were able to perform a leg lift within the normal range. A mean RMDQ score of 4.0 positive items (SD 6.0) was found, and the mean VAS Spinal Score was 79.4 (SD 25.0), both better than in other series. No significant differences compared to the values of a comparable (healthy) age group could be identified in any variable of the SF36. A high correlation was seen between RMDQ, VAS Spine Score and the SF36 categories. No correlation was found between the anterior wedge angle and the regional angle on the one hand, and functional capacity tests or questionnaire scores on the other. Of the patients in paid employment before the trauma, 87% had returned to work at follow-up. About 50% of the patients had been obliged to change the intensity of their work or the kind of work they performed after the injury and treatment. In this matter, leg (muscle) performance seems a more important factor than overall condition (VO2-max). The results of the study indicate that patients with thoracolumbar spinal fractures without neurological deficit, treated with dorsal instrumentation, perform like healthy people 3-8 years after injury, according to the RMDQ, VAS Spine Score and SF36 results. Physical capacity tests reveal that leg (muscle) performance seems a more important factor in impairment than arm lift or overall condition.


Assuntos
Fixadores Internos/estatística & dados numéricos , Vértebras Lombares/lesões , Vértebras Lombares/cirurgia , Fraturas da Coluna Vertebral/cirurgia , Fusão Vertebral/estatística & dados numéricos , Vértebras Torácicas/lesões , Vértebras Torácicas/cirurgia , Atividades Cotidianas , Adulto , Dor nas Costas/etiologia , Dor nas Costas/cirurgia , Tolerância ao Exercício/fisiologia , Feminino , Humanos , Vértebras Lombares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Debilidade Muscular/etiologia , Debilidade Muscular/cirurgia , Qualidade de Vida , Radiografia , Recuperação de Função Fisiológica/fisiologia , Licença Médica/estatística & dados numéricos , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/reabilitação , Inquéritos e Questionários , Vértebras Torácicas/diagnóstico por imagem , Resultado do Tratamento
4.
Br J Cancer ; 88(6): 843-7, 2003 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-12644820

RESUMO

We assessed the external validity of a prediction rule for nonseminomatous testicular cancer patients. The rule was developed to predict the probability of retroperitoneal metastases being benign (only necrosis/fibrosis) after chemotherapy treatment. Patients with a high probability of benign residual masses might be offered surveillance as opposed to patients with a low probability, who should undergo retroperitoneal lymph node dissection (RPLND). We compared the observed histology with the predicted probability in 105 patients with good prognosis germ cell cancer who underwent RPLND between 1995 and 1998. We found that predicted probabilities higher than 5% were in good agreement with the observed frequencies of benign masses. The area under the receiver operating characteristic curve was 0.76, suggesting that the rule could reasonably discriminate between benign masses and tumour. However, nearly all predicted probabilities (n=101) were lower than 70%, which might be considered as the lowest value at which surveillance offers a reasonable alternative to RPLND. Further, 35% of patients currently under surveillance (84 out of 241) had predicted probabilities lower than 70%. In conclusion, the clinical relevance of the prediction rule was limited for the patients who underwent RPLND; use of the rule would change the policy from RPLND to surveillance in only a few. On the other hand, the rule might support selection of patients for RPLND, who currently are under surveillance.


Assuntos
Modelos Estatísticos , Neoplasias Retroperitoneais/secundário , Neoplasias Testiculares/patologia , Fibrose , Humanos , Metástase Linfática , Masculino , Necrose , Neoplasia Residual , Valor Preditivo dos Testes , Neoplasias Testiculares/tratamento farmacológico
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.
Ann Oncol ; 13(1): 81-6, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11865814

RESUMO

BACKGROUND: Trimetrexate (TMTX) is a biochemical modulator of 5-fluorouracil (5-FU) and leucovorin (LV). Phase II trials have shown promising activity of 5-FU/LV/TMTX in patients with advanced colorectal cancer (ACC). This trial evaluated the effect of TMTX in combination with 5-FU/LV as first-line treatment in ACC. PATIENTS AND METHODS: Patients with ACC were randomised to receive either intravenous LV 200 mg/m2/5-FU 600 mg/m2 or TMTX 110 mg/m2 followed 24 h later by LV 200 mg/m2/5-FU 500 mg/m2 plus oral LV rescue. Both schedules were given weekly for 6 weeks every 8 weeks. Patients were evaluated for progression-free survival (PFS), overall survival (OS), tumour response, quality of life (QoL) and toxicity. RESULTS: A total of 365 patients were randomised. A statistically significant prolongation of median PFS was seen in patients treated with TMTX/5-FU/LV compared with 5-FU/LV (5.4 months versus 4.1 months, respectively; P = 0.03), and a trend towards a significant benefit for OS (13.4 months versus 10.5 months, respectively; P = 0.08). Tumour response, QoL and toxicity were comparable between the two arms. Diarrhoea was the most frequently occurring grade 3 or 4 toxicity (22% and 30%, respectively). CONCLUSIONS: The addition of TMTX to a weekly regimen of 5-FU/LV results in a small but significant improvement in PFS without adding toxicity or worsening QoL in patients with ACC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Fluoruracila/uso terapêutico , Leucovorina/uso terapêutico , Trimetrexato/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias Colorretais/patologia , Progressão da Doença , Europa (Continente) , Feminino , Fluoruracila/efeitos adversos , Humanos , Leucovorina/efeitos adversos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Taxa de Sobrevida , Trimetrexato/efeitos adversos , Trimetrexato/farmacologia
7.
Biopharm Drug Dispos ; 22(3): 99-108, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11745912

RESUMO

The distribution of ifosfamide (IF) and its metabolites 2-dechloroethylifosfamide (2DCE), 3-dechloroethylifosfamide (3DCE), 4-hydroxyifosfamide (4OHIF) and ifosforamide mustard (IFM) between plasma and erythrocytes was examined in vitro and in vivo. In vitro distribution was investigated by incubating blood with various concentrations of IF and its metabolites. In vivo distribution of IF, 2DCE, 3DCE and 4OHIF was determined in 7 patients receiving 9 g/m(2)/72 h intravenous continuous IF infusion. In vitro distribution equilibrium between erythrocytes and plasma was obtained quickly after drug addition. Mean (+/-sem) in vitro and in vivo erythrocyte (e)-plasma (p) partition coefficients (P(e/p)) were 0.75+/-0.01 and 0.81+/-0.03, 0.62+/-0.09 and 0.73+/-0.05, 0.76+/-0.10 and 0.93+/-0.05 and 1.38+/-0.04 and 0.98+/-0.09 for IF, 2DCE, 3DCE and 4OHIF, respectively. These ratios were independent of concentration and unaltered with time. The ratios of the area under the erythrocyte and plasma concentration--time curves (AUC(e/p)) were 0.96+/-0.03, 0.87+/-0.07, 0.98+/-0.06 and 1.34+/-0.39, respectively. A time- and concentration-dependent distribution--equilibrium phenomenon was observed with the relative hydrophilic IFM. It is concluded that IF and metabolites rapidly reach distribution equilibrium between erythrocytes and plasma; the process is slower for IFM. Drug distribution to the erythrocyte fraction ranged from about 38% for 2DCE to 58% for 4OHIF, and was stable over a wide range of clinically relevant concentrations. A strong parallelism in the erythrocyte and plasma concentration profiles was observed for all compounds. Thus, pharmacokinetic assessment using only plasma sampling yields direct and accurate insights into the whole blood kinetics of IF and metabolites and may be used for pharmacokinetic-pharmacodynamic studies.


Assuntos
Antineoplásicos Alquilantes/sangue , Eritrócitos/metabolismo , Ifosfamida/sangue , Plasma/metabolismo , Antineoplásicos Alquilantes/química , Antineoplásicos Alquilantes/farmacocinética , Área Sob a Curva , Humanos , Ifosfamida/química , Ifosfamida/farmacocinética
8.
Eur J Clin Pharmacol ; 57(6-7): 467-77, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11699611

RESUMO

OBJECTIVE: The population pharmacokinetics and pharmacodynamics of the cytostatic agent ifosfamide and its main metabolites 2- and 3-dechloroethylifosfamide and 4-hydroxyifosfamide were assessed in patients with soft tissue sarcoma. METHODS: Twenty patients received 9 or 12 g/m2 ifosfamide administered as a 72-h continuous intravenous infusion. The population pharmacokinetic model was built in a sequential manner, starting with a covariate-free model and progressing to a covariate model with the aid of generalised additive modelling. RESULTS: The addition of the covariates weight, body surface area, albumin, serum creatinine, serum urea, alkaline phosphatase and lactate dehydrogenase improved the prediction errors of the model. Typical pretreatment (mean +/- SEM) initial clearance of ifosfamide was 3.03 +/- 0.18 l/h with a volume of distribution of 44.0 +/- 1.8 l. Autoinduction, dependent on ifosfamide levels, was characterised by an induction half-life of 11.5 +/- 1.0 h with 50% maximum induction at 33.0 +/- 3.6 microM ifosfamide. Significant pharmacokinetic-pharmacodynamic relationships (P = 0.019) were observed between the exposure to 2- and 3-dechloroethylifosfamide and orientational disorder, a neurotoxic side-effect. No pharmacokinetic-pharmacodynamic relationships between exposure to 4-hydroxyifosfamide and haematological toxicities could be observed in this population.


Assuntos
Antineoplásicos Alquilantes/farmacocinética , Ciclofosfamida/análogos & derivados , Ifosfamida/análogos & derivados , Ifosfamida/farmacocinética , Sarcoma/metabolismo , Adulto , Idoso , Algoritmos , Antineoplásicos Alquilantes/uso terapêutico , Antineoplásicos Alquilantes/urina , Ciclofosfamida/sangue , Ciclofosfamida/urina , Feminino , Humanos , Ifosfamida/sangue , Ifosfamida/uso terapêutico , Ifosfamida/urina , Infusões Intravenosas , Masculino , Taxa de Depuração Metabólica , Pessoa de Meia-Idade , Modelos Biológicos , Sarcoma/tratamento farmacológico
9.
Drug Metab Dispos ; 29(7): 967-75, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11408362

RESUMO

The anticancer drug ifosfamide is a prodrug requiring activation through 4-hydroxyifosfamide to ifosforamide mustard, to exert cytotoxicity. Deactivation of ifosfamide leads to 2- and 3-dechloroethylifosfamide and the release of potentially neurotoxic chloracetaldehyde. The aim of this study was to quantify and to compare the pharmacokinetics of ifosfamide, 2- and 3-dechloroethylifosfamide, 4-hydroxyifosfamide, and ifosforamide mustard in short (1-4 h), medium (24-72 h), and long infusion durations (96-240 h) of ifosfamide. An integrated population pharmacokinetic model was used to describe the autoinducible pharmacokinetics of ifosfamide and its four metabolites in 56 patients. The rate by which autoinduction of the metabolism of ifosfamide developed was found to be significantly dependent on the infusion schedule. The rate was 52% lower with long infusion durations compared with short infusion durations. This difference was, however, comparable with its interindividual variability (22%) and was, therefore, considered to be of minor clinical importance. Autoinduction caused a less than proportional increase in the area under the ifosfamide plasma concentration-time curve (AUC) and more than proportional increase in metabolite exposure with increasing ifosfamide dose. During long infusion durations dose-corrected exposures (AUC/D) were significantly decreased for ifosfamide and increased for 3-dechloroethylifosfamide compared with short infusion durations. No differences in dose-normalized exposure to ifosfamide and metabolites were observed between short and medium infusion durations. This study demonstrates that the duration of ifosfamide infusion influences the exposure to the parent and its metabolite 3-dechloroethylifosfamide. The observed dose and infusion duration dependence should be taken into account when modeling ifosfamide metabolism.


Assuntos
Antineoplásicos Alquilantes/farmacocinética , Ifosfamida/farmacocinética , Antineoplásicos Alquilantes/administração & dosagem , Área Sob a Curva , Teorema de Bayes , Cromatografia Gasosa , Relação Dose-Resposta a Droga , Esquema de Medicação , Humanos , Ifosfamida/administração & dosagem
10.
Ann Oncol ; 12(3): 357-63, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11332149

RESUMO

PURPOSE: A phase I trial of raltitrexed in combination with cisplatin in patients with locally advanced or metastatic squamous cell carcinoma of the head and neck (SCCHN). PATIENTS AND METHODS: Eligible patients had locally advanced or metastatic SCCHN. Cohorts of patients were treated with escalating doses of raltitrexed (2.0 mg/m2 to 3.5 mg/m2) as a 15-minute intravenous infusion immediately followed by cisplatin (80 mg/m2) administered over four hours every three weeks to determine the maximum tolerated dose (MTD). RESULTS: A total of 17 patients was administered 60 courses of an escalating dose of raltitrexed. Starting dose of cisplatin was initially 100 mg/m2 in the first three patients treated at the first dose level. Due to cisplatin-induced nephrotoxicity expressed as a creatinine clearance decrease by more than 50%, the cisplatin dose was reduced to 80 mg/m2 for all subsequent treatment cycles. Dose-limiting toxicity was observed at raltitrexed dose of 3.5 mg/m2 in two out of five patients. Dose-limiting grade 4 (CTC) neutropenia, grade 4 diarrhoea, grade 3 lethargy and elevation of transaminases and bilirubine was seen in these two patients. One patient treated at the level of the MTD, died 23 days after the first cycle with unresolved gastro-intestinal toxicity. In all other dose levels toxicity was very limited. The recommended dose for further study was raltitrexed 3.0 mg/m2 in combination with cisplatin 80 mg/m2. In 15 evaluable patients, we observed 9 WHO objective responses (1 complete and 8 partial). At the recommended dose level 3 partial responses were observed in five evaluable patients. CONCLUSION: The regimen of raltitrexed 3.0 mg/m2 followed by cisplatin 80 mg/m2 on day 1, every three weeks has manageable toxicity and these doses are recommended for phase II evaluation. Results indicate that this combination is active for the treatment of patients with locally advanced or metastatic SCCHN. Recently, a phase II study has been started.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Idoso , Antimetabólitos Antineoplásicos/administração & dosagem , Antineoplásicos/administração & dosagem , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/secundário , Cisplatino/administração & dosagem , Relação Dose-Resposta a Droga , Feminino , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Neutropenia/induzido quimicamente , Quinazolinas/administração & dosagem , Tiofenos/administração & dosagem , Resultado do Tratamento
11.
Clin Pharmacokinet ; 40(1): 41-62, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11236809

RESUMO

This review discusses several issues in the clinical pharmacology of the antitumour agent ifosfamide and its metabolites. Ifosfamide is effective in a large number of malignant diseases. Its use, however, can be accompanied by haematological toxicity, neurotoxicity and nephrotoxicity. Since its development in the middle of the 1960s, most of the extensive metabolism of ifosfamide has been elucidated. Identification of specific isoenzymes responsible for ifosfamide metabolism may lead to an improved efficacy/toxicity ratio by modulation of the metabolic pathways. Whether ifosfamide is specifically transported by erythrocytes and which activated ifosfamide metabolites play a key role in this transport is currently being debated. In most clinical pharmacokinetic studies, the phenomenon of autoinduction has been observed, but the mechanism is not completely understood. Assessment of the pharmacokinetics of ifosfamide and metabolites has long been impaired by the lack of reliable bioanalytical assays. The recent development of improved bioanalytical assays has changed this dramatically, allowing extensive pharmacokinetic assessment, identifying key issues such as population differences in pharmacokinetic parameters, differences in elimination dependent upon route and schedule of administration, implications of the chirality of the drug and interpatient pharmacokinetic variability. The mechanisms of action of cytotoxicity, neurotoxicity, urotoxicity and nephrotoxicity have been pivotal issues in the assessment of the pharmacodynamics of ifosfamide. Correlations between the new insights into ifosfamide metabolism, pharmacokinetics and pharmacodynamics will rationalise the further development of therapeutic drug monitoring and dose individualisation of ifosfamide treatment.


Assuntos
Antineoplásicos Alquilantes/farmacocinética , Ciclofosfamida/farmacocinética , Sistema Enzimático do Citocromo P-450/metabolismo , Ifosfamida/farmacocinética , Animais , Antineoplásicos Alquilantes/administração & dosagem , Antineoplásicos Alquilantes/efeitos adversos , Área Sob a Curva , Ciclofosfamida/administração & dosagem , Sistema Enzimático do Citocromo P-450/efeitos dos fármacos , Inibidores Enzimáticos , Síndrome de Fanconi/induzido quimicamente , Humanos , Ifosfamida/administração & dosagem , Ifosfamida/efeitos adversos , Azul de Metileno/uso terapêutico , Síndromes Neurotóxicas/tratamento farmacológico , Estereoisomerismo
12.
Ann Oncol ; 12(10): 1353-7, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11762804

RESUMO

Peritonitis carcinomatosa, indicating the presence of malignant cells in the peritoneal cavity, is a well-known complication of malignant disease. As a result, so-called malignant ascites develops. Malignant ascites is a debilitating condition for which no effective anti-tumor therapy is available. Frequent draining may be necessary to relieve pain and discomfort. Most studies regarding malignant ascites focus on diagnosis and treatment. In this paper. we will address the subject from a pathophysiologic perspective, using the characteristics of malignant ascites, Starling's equation of capillary forces, and recent knowledge regarding biologically active peptides produced by tumor cells. Following this approach. apart from decreased lymphatic ascites absorption, increased net capillary fluid-production can be identified as a contributing feature of ascites formation. The increased net filtration is due to an increase of overall capillary membrane-surface, increased capillary permeability and a subsequent increase of intraperitoneal protein concentration leading to increased intraperitoneal oncotic pressure. This sequence might be the result of biologically active peptides produced by tumor cells such as vascular endothelial growth factor and basic fibroblast growth factor. Interference with these mediators may serve as a target in future therapeutic strategies.


Assuntos
Ascite/fisiopatologia , Modelos Biológicos , Neovascularização Patológica , Permeabilidade Capilar , Fatores de Crescimento Endotelial/farmacologia , Fator 2 de Crescimento de Fibroblastos/farmacologia , Filtração , Hemodinâmica , Humanos , Linfocinas/farmacologia , Metástase Neoplásica , Neoplasias/fisiopatologia , Fluxo Sanguíneo Regional , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
13.
Stat Med ; 20(24): 3847-59, 2001 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-11782038

RESUMO

After chemotherapy for metastatic non-seminomatous testicular cancer, surgical resection is a generally accepted treatment to remove remnants of the initial metastases, since residual tumour may still be present (mature teratoma or viable cancer cells). In this paper, we review the development and external validation of a logistic regression model to predict the absence of residual tumour. Three sources of information were used. A quantitative review identified six relevant predictors from 19 published studies (996 resections). Second, a development data set included individual data of 544 patients from six centres. This data set was used to assess the predictive relationships of five continuous predictors, which resulted in dichotomization for two, and a log, square root, and linear transformation for three other predictors. The multiple logistic regression coefficients were reduced with a shrinkage factor (0.95) to improve calibration, based on a bootstrapping procedure. Third, a validation data set included 172 more recently treated patients. The model showed adequate calibration and good discrimination in the development and in the validation sample (areas under the ROC curve 0.83 and 0.82). This study illustrates that a careful modelling strategy may result in an adequate predictive model. Further study of model validity may stimulate application in clinical practice.


Assuntos
Modelos Estatísticos , Metástase Neoplásica/patologia , Valor Preditivo dos Testes , Neoplasias Testiculares/patologia , Biomarcadores Tumorais , Humanos , Masculino , Análise Multivariada , Metástase Neoplásica/tratamento farmacológico , Análise de Regressão , Reprodutibilidade dos Testes , Neoplasias Testiculares/tratamento farmacológico , Neoplasias Testiculares/cirurgia
15.
J Clin Oncol ; 18(14): 2676-84, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10894866

RESUMO

PURPOSE: This randomized multicenter study was designed to compare the activity of a high-dose doxorubicin-containing chemotherapy regimen with a conventional standard-dose regimen in adult patients with advanced soft tissue sarcomas (ASTS). PATIENTS AND METHODS: Between 1992 and 1995, 314 patients were randomized to receive a standard-dose regimen (arm A), containing doxorubicin (50 mg/m(2) on day 1) and ifosfamide (5 g/m(2) on day 1), or an intensified regimen (arm B), combining doxorubicin (75 mg/m(2) on day 1), the same ifosfamide dose, and recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF; sargramostim, 250 microgram/m(2) on days 3 to 16); all courses were repeated every 3 weeks. RESULTS: The median age of the 294 eligible patients was 50 years. They received a median of five chemotherapy cycles. The median dose and relative doxorubicin dose-intensity achieved were 245 mg and 97% in arm A and 360 mg and 99% in arm B, respectively. Thirty-eight percent and 23% of patients presented with leiomyosarcomas and liver metastases, respectively. Objective responses were observed in 31 (21%) of 147 assessable patients in arm A and in 31 (23.3%) of 133 in arm B (P =.65). No change was observed in 41.6% and 46.2% of patients in arm A and B, respectively. Progression-free survival (PFS) was significantly longer in the intensive arm (P =.03). The median duration of the time to progression was 19 weeks in the conventional arm and 29 weeks in the intensified arm. There was no difference in overall survival (P =.98) between the two therapeutic arms. Toxicities were manageable in both arms. A grade 3/4 neutropenia and infection occurred in 92% and 4.6% of patients in arm A, respectively, and in 90% and 16.6% in arm B, respectively. Grade 3/4 thrombocytopenia was more frequent in arm B. CONCLUSION: The use of rhGM-CSF allowed safe escalation of chemotherapy doses. Despite a 50% increase of the doxorubicin dose-intensity, the high-dose regimen failed to demonstrate any impact on survival in patients with ASTS. The low complete response rate, the high incidence of leiomyosarcomas, and liver metastases may in part explain these results. However, the lengthening of the PFS in the intensive arm, because of the quality of stable disease and inappropriate tumor evaluation policies that potentially lead to an underestimation of antitumor activity, does not definitively refute the use of a high-dose chemotherapy regimen in selected patients with ASTS.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Fator Estimulador de Colônias de Granulócitos e Macrófagos/uso terapêutico , Sarcoma/tratamento farmacológico , Adulto , Idoso , Doxorrubicina/administração & dosagem , Esquema de Medicação , Feminino , Humanos , Ifosfamida/administração & dosagem , Leiomiossarcoma/tratamento farmacológico , Leiomiossarcoma/secundário , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/secundário , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes , Sarcoma/secundário , Análise de Sobrevida
16.
Br J Clin Pharmacol ; 49(6): 555-61, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10848719

RESUMO

AIMS: This study investigated the population pharmacokinetics of ifosfamide in 15 patients treated for soft tissue sarcoma with 9 or 12 g m-2 ifosfamide by means of a 72 h continuous i.v. infusion. METHODS: A model was developed using nonlinear mixed effects modelling (NONMEM) to describe the nonlinear pharmacokinetics of ifosfamide by linking the ifosfamide plasma concentrations to the extent of the autoinduction. RESULTS: The proposed model revealed the effect of autoinduction on the disposition of ifosfamide. The initial clearance, volume of distribution, rate constant for enzyme degradation, induction half-life of the enzyme and the ifosfamide concentration at 50% of the maximum inhibition of enzyme degradation were estimated at 2.94 +/- 0.27 l h-1, 43.5 +/- 2.9 l, 0.0546 +/- 0. 0078 h-1, 12.7 h and 30.7 +/- 4.8 microM, respectively. Interindividual variabilities of initial clearance, volume of distribution, rate constant for enzyme degradation were 24.5, 23.4 and 22.7%, respectively. Proportional and additive variability not explained by the model were 13.6% and 0.0763 microM, respectively. CONCLUSIONS: The absence of a lag time for the autoinduction of ifosfamide metabolism could be the result of an immediate inhibition of the enzymatic degradation of CYP3A4 by ifosfamide. By application of the autoinduction model individual pharmacokinetic profiles of patients were described with adequate precision. This model may therefore be used in the future development of a model to individualize dose selection in patients.


Assuntos
Antineoplásicos Alquilantes/farmacocinética , Ifosfamida/farmacocinética , Adulto , Idoso , Algoritmos , Antineoplásicos Alquilantes/uso terapêutico , Área Sob a Curva , Simulação por Computador , Feminino , Humanos , Ifosfamida/uso terapêutico , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Farmacocinética , População , Sarcoma/tratamento farmacológico , Sarcoma/metabolismo , Neoplasias de Tecidos Moles/tratamento farmacológico , Neoplasias de Tecidos Moles/metabolismo , Software
17.
Radiology ; 215(2): 437-44, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10796922

RESUMO

PURPOSE: To determine the relative importance of computed tomographic (CT) measurements for the prediction of histologic findings in residual masses in patients with nonseminomatous testicular cancer. MATERIALS AND METHODS: Measurements of the maximum transverse size of retroperitoneal metastases before and after chemotherapy were available in 641 patients who underwent resection after chemotherapy while their levels of tumor markers were normal. Radiologic measurements of mass size and clinical characteristics (histologic findings in primary tumor and levels of alpha-fetoprotein, human chorionic gonadotropin, and lactate dehydrogenase before chemotherapy) were related to histologic findings in the residual mass with logistic regression analysis. RESULTS: At resection, 302 patients had benign tissue, and 339 had residual tumor (mature teratomas or cancer). Tumor was more frequent in larger masses after chemotherapy but was unrelated to mass size before chemotherapy. Inclusion of the reduction in size significantly improved the logistic regression model, which included mass size after chemotherapy. This model was further improved with the addition of clinical characteristics. Areas under the receiver operating characteristic curves increased from 0.74 to 0.77 and 0.83 with these models. CONCLUSION: A small retroperitoneal mass after chemotherapy is an important predictor of benign histologic findings in residual masses in patients with nonseminomatous testicular cancer. However, better predictions can be made when the reduction in size and clinical characteristics are considered as well. Decisions regarding resection should be based on the combination of these characteristics rather than on only mass size after chemotherapy.


Assuntos
Tomada de Decisões , Planejamento de Assistência ao Paciente , Neoplasias Retroperitoneais/secundário , Neoplasias Testiculares/patologia , Tomografia Computadorizada por Raios X , Área Sob a Curva , Biomarcadores Tumorais/análise , Carcinoma/tratamento farmacológico , Carcinoma/patologia , Carcinoma/secundário , Carcinoma/cirurgia , Gonadotropina Coriônica/análise , Previsões , Humanos , L-Lactato Desidrogenase/análise , Modelos Logísticos , Metástase Linfática , Masculino , Neoplasia Residual/patologia , Razão de Chances , Estudos Prospectivos , Curva ROC , Neoplasias Retroperitoneais/tratamento farmacológico , Neoplasias Retroperitoneais/patologia , Neoplasias Retroperitoneais/cirurgia , Teratoma/tratamento farmacológico , Teratoma/patologia , Teratoma/secundário , Teratoma/cirurgia , alfa-Fetoproteínas/análise
18.
Br J Cancer ; 82(9): 1539-46, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10789721

RESUMO

A phase I dose-escalation study was performed to determine whether isolated hepatic perfusion (IHP) with melphalan (L-PAM) allows exposure of the liver to much higher drug concentrations than clinically achievable after systemic administration and leads to higher tumour concentrations of L-PAM. Twenty-four patients with colorectal cancer confined to the liver were treated with L-PAM dosages escalating from 0.5 to 4.0 mg kg(-1). During all IHP procedures, leakage of perfusate was monitored. Duration of IHP was aimed at 60 min, but was shortened in eight cases as a result of leakage from the isolated circuit. From these, three patients developed WHO grade 3-4 leukopenia and two patients died due to sepsis. A reversible elevation of liver enzymes and bilirubin was seen in the majority of patients. Only one patient was treated with 4.0 mg kg(-1) L-PAM, who died 8 days after IHP as a result of multiple-organ failure. A statistically significant correlation was found between the dose of L-PAM, peak L-PAM concentrations in perfusate (R = 0.86, P< or =0.001), perfusate area under the concentration-time curve (AUC; R = 0.82, P<0.001), tumour tissue concentrations of L-PAM (R = 0.83, P = 0.011) and patient survival (R = 0.52, P = 0.02). The peak L-PAM concentration and AUC of L-PAM in perfusate at dose level 3.0 mg kg(-1) (n = 5) were respectively 35- and 13-fold higher than in the systemic circulation, and respectively 30- and 5-fold higher than reported for high dose oral L-PAM (80-157 mg m(-2)) and autologous bone marrow transplantation. Median survival after IHP (n = 21) was 19 months and the overall response rate was 29% (17 assessable patients; one complete and four partial remissions). Thus, the maximally tolerated dose of L-PAM delivered via IHP is approximately 3.0 mg kg(-1), leading to high L-PAM concentrations at the target side. Because of the complexity of this treatment modality, IHP has at present no place in routine clinical practice.


Assuntos
Antineoplásicos Alquilantes/administração & dosagem , Quimioterapia do Câncer por Perfusão Regional , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Melfalan/administração & dosagem , Antineoplásicos Alquilantes/efeitos adversos , Antineoplásicos Alquilantes/farmacocinética , Área Sob a Curva , Neoplasias Colorretais/patologia , Humanos , Neoplasias Hepáticas/secundário , Melfalan/efeitos adversos , Melfalan/farmacocinética , Análise de Sobrevida , Resultado do Tratamento
19.
J Clin Oncol ; 18(10): 2169-78, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10811682

RESUMO

PURPOSE: To evaluate the risk of major thromboembolic complications in male germ cell cancer patients receiving cisplatin-based chemotherapy and to review the literature on this subject. PATIENTS AND METHODS: One hundred seventy-nine germ cell cancer patients treated between January 1979 and May 1997 in our hospital were analyzed with respect to risk factors for developing thromboembolic events, such as baseline tumor characteristics, prior tumor therapy, administration of cytostatic agents, and the use of antiemetic drugs. The patients were treated with a variety of combination chemotherapy regimens, primarily cisplatin-containing combination regimens. RESULTS: Of the 179 patients, 15 patients (8.4%) were identified who developed a total of 18 major thromboembolic complications in the time period between the start of chemotherapy and 6 weeks after administration of the last cytostatic drug in first-line treatment. Of these 18 events, three (16.7%) were arterial events, including two cerebral ischemic strokes, and 15 (83. 3%) were venous thromboembolic events, including 11 pulmonary embolisms. One (5.6%) of the 18 events was fatal. Liver metastases (odds ratio, 4.9; 95% confidence interval, 1.1 to 20.8) and the administration of high doses of corticosteroids (>/= 80 mg dexamethasone per cycle; odds ratio, 3.5; 95% confidence interval, 1. 2 to 10.3) as antiemetic therapy were identified as risk factors for the development of major thromboembolic complications. CONCLUSION: Germ cell cancer patients who receive chemotherapy, in particular those who have liver metastases or receive high doses of corticosteroids, are at considerable risk of developing thromboembolic complications.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Cisplatino/efeitos adversos , Germinoma/tratamento farmacológico , Neoplasias Testiculares/tratamento farmacológico , Tromboembolia/induzido quimicamente , Bleomicina/efeitos adversos , Estudos de Coortes , Humanos , Incidência , Modelos Logísticos , Masculino , Estudos Retrospectivos , Fatores de Risco , Tromboembolia/epidemiologia
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