RESUMO
AIMS: The British Oncology Network for Undergraduate Societies (BONUS) surveyed students who attended an oncology revision day to determine their views on the current quantity, quality and type of curriculum-based oncology teaching they have experienced. MATERIALS AND METHODS: Students attending two BONUS revision days received a questionnaire assessing their experience of oncology teaching within the medical curriculum and interest in pursuing a future career in oncology using a 10-point Likert scale. Data were collected with informed consent to be anonymised and used for research. Student demographics and qualitative and quantitative data about experiences of oncology education were analysed. RESULTS: In total, 451 students registered to attend the revision days. After removal of duplicates, non-responders and non-UK participants, responses from 153 students studying across years 1-6 at 22 UK medical schools were analysed. The mean quantity of oncology lectures students reported receiving was 8.9 hours and the mean quantity of clinic/ward-based oncology teaching was 7.5 hours. Ninety (62.1%) of the 145 students who responded to the relevant question reported that they had received dedicated teaching in oncology. Students who had received dedicated oncology teaching reported a statistically significantly higher mean quality 6.1 (95% confidence interval 5.6-6.5) versus 5.0 (95% confidence interval 4.3-5.5; P = 0.003) and quantity 5.2 (95% confidence interval 4.7-5.6) versus 4.3 (95% confidence interval 3.7-4.9; P = 0.03) of oncology teaching compared with those who had not received this. CONCLUSION: Appropriate oncology education is essential for all medical students due to the high prevalence of cancer. All future doctors need the appropriate knowledge and communication skills to care for cancer patients. Our analysis provides quantitative evidence to support the value of specialist oncology teaching within the medical school curriculum in improving student-reported experience. National student-led revision days and events may widen interest in a future career in oncology and aid collaboration between oncology societies. It is important for the general undergraduate medical curriculum to integrate specialty content. An integrated curriculum should facilitate a holistic approach that spans prevention, screening, treatment and palliation rather than being split by subspeciality.
Assuntos
Educação de Graduação em Medicina , Estudantes de Medicina , Currículo , Humanos , Oncologia , Reino UnidoRESUMO
BACKGROUND: Frailty is a state of vulnerability to poor resolution of homeostasis following a stressor event, such as chemotherapy or cancer surgery. Better knowledge of the epidemiology of frailty could help drive a global cancer care strategy for older people. The aim of this review was to establish the prevalence and outcomes of frailty and pre-frailty in older cancer patients. METHODS: Observational studies that reported data on the prevalence and/or outcomes of frailty in older cancer patients with any stage of solid or haematological malignancy were considered. We searched Medline, CINAHL, Cochrane Library, EMBASE, Web of Science, Allied and Complementary medicine, Psychinfo and ProQuest (1 January 1996 to 30 June 2013). The primary outcomes were prevalence of frailty, treatment-related side-effects, unplanned hospitalization and mortality. Risk of bias was assessed using the Newcastle-Ottawa checklist. RESULTS: Data from 20 studies evaluating 2916 participants are included. The median reported prevalence of frailty and pre-frailty was 42% (range 6%-86%) and 43% (range 13%-79%), respectively. A median of 32% (range 11%-78%) of patients were classified as fit. Frailty was independently associated with increased all-cause mortality [adjusted 5-year hazard ratio (HR) 1.87, 95% confidence interval (CI) 1.36-2.57]. There was evidence of increased risk of postoperative mortality for both frailty (adjusted 30-day HR 2.67, 95% CI 1.08-6.62) and pre-frailty (adjusted HR 2.33, 95% CI 1.20-4.52). Treatment complications were more frequent in those with frailty, including intolerance to cancer treatment (adjusted odds ratio 4.86, 95% CI 2.19-10.78) and postoperative complications (adjusted 30-day HR 3.19, 95% CI 1.68-6.04). CONCLUSIONS: More than half of older cancer patients have pre-frailty or frailty and these patients are at increased risk of chemotherapy intolerance, postoperative complications and mortality. The findings of this review support routine assessment of frailty in older cancer patients to guide treatment decisions, and the development of multidisciplinary geriatric oncology services.
Assuntos
Antineoplásicos/uso terapêutico , Idoso Fragilizado , Neoplasias/epidemiologia , Neoplasias/terapia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/efeitos adversos , Comorbidade , Feminino , Avaliação Geriátrica , Humanos , Masculino , Neoplasias/diagnóstico , Neoplasias/mortalidade , Razão de Chances , Complicações Pós-Operatórias/epidemiologia , Valor Preditivo dos Testes , Prevalência , Fatores de Risco , Resultado do TratamentoRESUMO
Existing local therapies for superficial transitional cell carcinoma (TCC) of the bladder have limited success in preventing progression to life-threatening, muscle-invasive disease, and novel therapies are needed. Recent studies have raised doubts concerning the feasibility of adenovirus-mediated gene therapy for bladder cancer. We have therefore investigated adenoviral transduction of normal and malignant human urothelial cells, both as primary cultures and in intact epithelium. All 15 primary normal human urothelial cell lines tested were transduced in vitro by Adv-cmv-beta-gal at high efficiency, and better than most human TCC cell lines. Eight primary human TCC explants were also successfully transduced. In contrast, in intact normal urothelium, transduction efficiency was lower, and occurred only in superficial epithelial layers. Expression of the hCAR adenovirus receptor, however, occurred throughout the full thickness of urothelium. Transduction of human TCC biopsy specimens was at least as efficient as intact normal urothelium.We demonstrate for the first time that adenoviral transduction of both normal and malignant human urothelial cells is feasible. A physical barrier, rather than hCAR status, may be the main determinant of transduction of intact epithelium. Clinical trials of adenovirus-mediated gene therapy for superficial bladder cancer are warranted.
Assuntos
Adenovírus Humanos/genética , Carcinoma de Células de Transição/terapia , Terapia Genética/métodos , Vetores Genéticos/administração & dosagem , Transdução Genética/métodos , Neoplasias da Bexiga Urinária/terapia , Células Cultivadas , Ácido Edético , Imunofluorescência , Marcação de Genes/métodos , Vetores Genéticos/genética , Humanos , Tripsina , Células Tumorais Cultivadas , Urotélio/metabolismo , beta-Galactosidase/genéticaRESUMO
The aim of this study was to determine whether clodronate reduced the incidence of vertebral fractures in patients with osteoporosis. We report here the interim analysis after 1 year of a 3-year double-blind placebo-controlled study. The objectives of the interim analysis were to determine whether there was a trend in fracture frequency and to examine the effects of clodronate on bone mineral density (BMD). Patients with densitometrically proven osteoporosis (T-score <-2.5 and <-3 for women and men, respectively) or with at least one prevalent vertebral fracture were recruited to a 3-year double-blind, controlled study. Patients were randomized to three strata, namely women with postmenopausal osteoporosis (stratum I, n = 483), women with secondary osteoporosis (II, n = 110), and men with osteoporosis of any causation (III, n = 84). They received either clodronate 800 mg daily by mouth or an identical placebo, and all patients received a calcium supplement of 500 mg daily. BMD was measured at six monthly intervals, and lateral spine radiographs for vertebral morphometry were obtained at baseline and 1 year. Treatment with clodronate was associated with a significant increase in BMD at the spine of 3.2 +/- 0.3% (p < 0.0001 vs. baseline) compared with a nonsignificant change of 0.5 +/- 0.3% in the placebo group (p < 0.0001 between treatments). At the hip, clodronate was associated with a significant increase in total hip BMD of 1.3 +/- 0.3% (p = 0.018 vs. baseline) compared with a small decrease of 0.4 +/- 0.3% in the placebo group (p = 0.027 for the difference between treatment groups). The mean changes at the spine and hip were similar in all three strata. Incident vertebral fractures were observed in 27 patients at 1 year in the placebo group (9.0%) and in 14 patients receiving clodronate (4.9%) (relative risk 0.54; 95% CI 0.29-1.02; p = 0.07). A trend was observed in all treatment strata. Treatment was well tolerated, with no significant adverse events attributable to clodronate treatment. We conclude that clodronate 800 mg daily is effective in preventing bone loss, and at 1 year, there is a trend consistent with antifracture efficacy in patients with established osteoporosis regardless of causation.
Assuntos
Ácido Clodrônico/uso terapêutico , Osteoporose/complicações , Fraturas da Coluna Vertebral/prevenção & controle , Densidade Óssea , Feminino , Humanos , Incidência , Masculino , Medição de Risco , Fraturas da Coluna Vertebral/epidemiologia , Fraturas da Coluna Vertebral/etiologia , Reino Unido/epidemiologiaRESUMO
BACKGROUND: Low bone mineral density (BMD) is prevalent in adults with cystic fibrosis. The aim of this study was to assess the effect of intravenous pamidronate on BMD in these subjects. METHODS: Patients were invited to participate if they had a BMD Z score of -2 or less in the lumbar spine, proximal femur, or distal forearm. Patients were randomised to receive either 30 mg intravenous pamidronate every 3 months + 1 g calcium daily (pamidronate group) or 1 g calcium daily (control group). All pancreatic insufficient patients were prescribed oral vitamin D supplements. RESULTS: After 6 months of treatment the pamidronate group (n=13) showed a significant increase in absolute BMD compared with the control group (n=15) in the lumbar spine (mean difference 5.8% (CI 2.7% to 8.9%)) and total hip (mean difference 3.0% (CI 0.3% to 5.6%)). However, the pamidronate group showed a reduction in BMD compared with the control group in the distal forearm (mean difference -1.7% (CI -3.7% to 0.3%)). The use of pamidronate was associated with a high incidence of bone pain in non-corticosteroid treated individuals. CONCLUSION: Intravenous pamidronate increases axial BMD in adults with cystic fibrosis, but the high incidence of bone pain associated with this treatment might limit its use.
Assuntos
Anti-Inflamatórios/administração & dosagem , Densidade Óssea/efeitos dos fármacos , Doenças Ósseas Metabólicas/prevenção & controle , Fibrose Cística/fisiopatologia , Difosfonatos/administração & dosagem , Adolescente , Adulto , Anti-Inflamatórios/efeitos adversos , Cálcio/administração & dosagem , Fibrose Cística/complicações , Fibrose Cística/tratamento farmacológico , Difosfonatos/efeitos adversos , Humanos , Infusões Intravenosas , Estudos Longitudinais , Pessoa de Meia-Idade , Pamidronato , Resultado do TratamentoRESUMO
BACKGROUND: Patients with cystic fibrosis have several risk factors for the development of low bone mineral density (BMD). To identify the prevalence and clinical correlates of low BMD in adult patients with cystic fibrosis, densitometry was performed in 151 patients (83 men) aged 15-52 years. METHODS: BMD was measured in the lumbar spine (L1-4) using dual energy x ray absorptiometry (DXA) and quantitative computed tomography (QCT). It was also measured in the proximal femur (total hip and femoral neck) using DXA, and in the distal and ultra distal forearm using single energy x ray absorptiometry (SXA). Biochemical markers of bone turnover, vitamin D levels, parathyroid hormone levels, and a variety of anthropometric variables were also assessed. RESULTS: The mean (SD) BMD Z score was -0.73 (0.85) in the distal forearm, -0.31 (0.92) in the ultra distal forearm, -1.21 (1. 18) in the lumbar spine using DXA, -0.56 (1.36) in the lumbar spine using QCT, -1.25 (1.30) in the femoral neck, and -1.01 (1.14) in the total hip. 34% of patients had a BMD Z score of -2 or less at one or more skeletal sites. Body mass index (0.527, p = 0.01), percentage predicted forced expiratory volume in one second (0.388, p = 0.01), and physical activity (0.249, p = 0.05) were positively related to the mean BMD Z score. Levels of C reactive protein (-0.328, p = 0. 01), parathyroid hormone (-0.311, p = 0.01) and biochemical markers of bone turnover (osteocalcin -0.261 and bone specific alkaline phosphatase -0.249, p = 0.05) were negatively related to the mean BMD Z score. Vitamin D insufficiency (25-hydroxyvitamin D <15 ng/ml) was prevalent (53/139 patients, 38%) despite supplementation with 900 IU vitamin D per day. CONCLUSIONS: Low bone density is prevalent in adult patients with cystic fibrosis. Current levels of vitamin D supplementation appear to be inadequate.
Assuntos
Densidade Óssea/fisiologia , Fibrose Cística/fisiopatologia , Deficiência de Vitamina D/metabolismo , Adolescente , Adulto , Densitometria , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , PrevalênciaRESUMO
Serum vitamin D metabolites and PTH were measured in seven subjects with a history of previous partial gastrectomy (PGX) and metabolic bone disease. The elimination t1/2 of [3H]25-hydroxyvitamin D3 ([3H]25OHD3) in serum was assessed after an iv pulse dose of 5 microCi [26,27-3H]25OHD3. Median serum 25OHD3 was 37.5 (27.5-101.3) nmol/L, [normal range (NR) 10.8-58.5 nmol/L], mean serum 1,25-dihydroxyvitamin D [1, 25-(OH)2D3] was raised at 175 +/- 72 pmol/L, (NR 48-120 pmol/L) and mean PTH was also high, 67 +/- 27 ng/L, (NR 10-60 ng/L). Serum t1/2 [3H]25OHD3 ranged from 10.9-21.2 days. A strong negative correlation existed between t1/2 [3H]25OHD3 and serum 1,25-(OH)2D3 [Spearman's rank correlation coefficient (r = -0.82, P = 0.002)] and PTH [Spearman's rank correlation coefficient (r = -0.81, P = 0.001)]. Four subjects who had high initial PTH concentrations (60-115 ng/L) and elevated 1,25-(OH)2D levels (162-300 pmol/L) were reassessed after calcium supplementation to suppress secondary hyperparathyroidism (2 degrees HPT). In this subgroup, after-treatment PTH fell from 82 +/- 24 to 52 +/- 24 ng/L (mean +/- SD), not significant; 1,25-(OH)2D fell from 210 +/- 61 to 116 +/- 28 pmol/L, P = 0.015; and t1/2 [3H]25OHD3 increased from 13.2 +/- 1.9 to 18.9 +/- 3.1 days, P = 0.012. Patients with PGX and evidence of 2 degrees HPT with elevated 1,25-(OH)2D have a reduced t1/2 [3H]25OHD3, and this may explain the increased susceptibility of the subjects to osteomalacia. Calcium supplementation suppresses 2 degrees HPT, increases t1/2 [3H]25OHD3 and may protect against PGX osteoporosis and osteomalacia.
Assuntos
Doenças Ósseas/etiologia , Calcifediol/sangue , Calcitriol/sangue , Gastrectomia , Idoso , Cálcio/administração & dosagem , Feminino , Meia-Vida , Humanos , Masculino , Pessoa de Meia-Idade , Osteomalacia/etiologia , Hormônio Paratireóideo/sangue , Valores de ReferênciaRESUMO
The circulating cytokine concentrations following administration of subcutaneous recombinant interleukin 2 (IL-2) in combination with interferon alpha and 5-fluorouracil used to treat advanced renal cancer were studied. One patient was anephric and on dialysis, and seven had normal biochemical renal function, although five had undergone single nephrectomy. The pharmacokinetics of IL-2 and changes in IL-6 and tumour necrosis factor (TNF)-alpha were essentially similar in all patients including the anephric patient, irrespective of the periods of dialysis, although at some time points, IL-2 concentrations were slightly higher in the anephric patient than in the others. These results show that for subcutaneous administration of low-dose IL-2, renal clearance of IL-2 is not important. This contrasts with high-dose, intravenous IL-2 where blood concentrations are higher and renal clearance seems to occur, perhaps because of saturation of the non-renal mechanisms of clearance. The subcutaneous route is certainly preferred if IL-2 is used in anephric patients and in those with impaired renal function, and it may be generally preferred for most purposes.
Assuntos
Carcinoma de Células Renais/terapia , Citocinas/metabolismo , Interleucina-2/administração & dosagem , Neoplasias Renais/terapia , Adulto , Idoso , Antimetabólitos Antineoplásicos/administração & dosagem , Antineoplásicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Bioensaio , Carcinoma de Células Renais/sangue , Citocinas/sangue , Interpretação Estatística de Dados , Feminino , Fluoruracila/administração & dosagem , Humanos , Imunoensaio , Injeções Subcutâneas , Interferon-alfa/administração & dosagem , Interleucina-2/sangue , Rim/metabolismo , Neoplasias Renais/sangue , Masculino , Pessoa de Meia-Idade , Nefrectomia , Fatores de TempoRESUMO
OBJECTIVE: To systematically and critically analyse and summarise the published evidence for the rational choice of pharmacologic treatment of the neonatal abstinence syndrome (NAS), a frequently observed condition in neonates born to mothers who are dependent on physically addicting drugs. DESIGN: Studies comparing different pharmacological agents for the treatment of NAS were identified utilising MEDLINE and additionally the references cited in pertinent articles. The identified studies were critically analysed regarding their study designs and outcome measures. The reported data for the comparative efficacy of the drugs were summarised and evaluated. RESULTS: Fourteen studies were identified, most of them comparing treatment of NAS with phenobarbital, paregoric or diazepam. However, none of these studies was conducted in a double-blind fashion. Frequently, treatment allocations were not properly randomised. Prenatal drug exposure varied and was often not sufficiently verified. Outcome measures and their evaluations differed widely. Due to the different study objectives and flaws in study design, a combined analysis of the published data in the form of a meta-analysis was not deemed possible. When attempting to compare efficacy, diazepam appears to be less efficacious in treating NAS than phenobarbital or paregoric. The relative efficacy of paregoric and phenobarbital appears to depend upon the antenatal exposure of the neonate and on the outcome measure of the study. Only two studies evaluate the efficacy of pure opioids, none of them in direct comparison to paregoric. It remains questionable whether paregoric, which contains the central stimulant camphor and a large amount of alcohol, should be the opioid of choice for the treatment of NAS. CONCLUSION: Most published studies were conducted prior to the development of clinical epidemiology and modern study design and thus yielded only very limited comparative data on the benefits of different treatment protocols. There is very little evidence regarding the efficacy of different pharmacological therapy regimens to treat NAS. More studies are required to produce the evidence needed to allow a rational choice between treatment modalities of NAS and thus to ensure optimal care of the neonates suffering from this condition.
Assuntos
Ensaios Clínicos como Assunto/normas , Síndrome de Abstinência Neonatal/tratamento farmacológico , Analgésicos Opioides/administração & dosagem , Analgésicos Opioides/uso terapêutico , Anticonvulsivantes/administração & dosagem , Anticonvulsivantes/uso terapêutico , Antipsicóticos/administração & dosagem , Antipsicóticos/uso terapêutico , Clorpromazina/administração & dosagem , Clorpromazina/uso terapêutico , Ensaios Clínicos como Assunto/métodos , Clonidina/administração & dosagem , Clonidina/uso terapêutico , Diazepam/administração & dosagem , Diazepam/uso terapêutico , Quimioterapia Combinada , Humanos , Hipnóticos e Sedativos/administração & dosagem , Hipnóticos e Sedativos/uso terapêutico , Recém-Nascido , MEDLINE , Metadona/administração & dosagem , Metadona/uso terapêutico , Morfina/administração & dosagem , Morfina/uso terapêutico , Ópio/administração & dosagem , Ópio/uso terapêutico , Parassimpatolíticos/administração & dosagem , Parassimpatolíticos/uso terapêutico , Fenobarbital/administração & dosagem , Fenobarbital/uso terapêutico , Simpatolíticos/administração & dosagem , Simpatolíticos/uso terapêuticoRESUMO
OBJECTIVE: To confirm the activity and evaluate the toxicity of the combination of subcutaneous interferon-alpha (IFN-alpha) and interleukin-2 (IL-2) with intravenous 5-fluorouracil (5-FU) in patients with advanced and recurrent renal carcinoma and of performance status 0-2. Additionally, to examine protease, complement and neutrophil activation as potential mediators of IL-2 toxicity. PATIENTS AND METHODS: Fifty-five patients were treated in an 8-week cycle with IFN-alpha (6 MU/m2 on day 1 in weeks 1 and 4 and thrice weekly in weeks 2-3, and 9 MU/m2 thrice weekly in weeks 5-8) IL-2 (20 MU/m2 on days 3-5 in weeks 1 and 4 and 5 MU/m2 thrice weekly in weeks 2-3) and 5-FU (750 mg/m2 on day 1 of weeks 5-8). Patients responding to the first cycle were eligible to continue with further cycles. Toxicity and effects on quality of life were assessed using World Health Organization criteria and the Rotterdam Symptom Checklist and Hospital Anxiety and Depression Scale. Serum levels of C3a, prekallikrein and elastase-alpha 1 proteinase inhibitor (elastase-alpha 1-antitrypsin) were assayed in a subset of patients before, during and after the administration of high-dose IL-2 in week 1. RESULTS: There were partial remissions in nine patients, with responses in 24% (95% CI 10-38%) of evaluable patients and 16% of all patients. Amongst 25 evaluable patients who had undergone nephrectomy, the response rate was 32% (95% CI 14-50%), whereas there was only one response amongst 22 patients who had not undergone nephrectomy. The median survival for patients with stable disease or partial remission exceeded 22 months. Outcome and survival were related to performance status, number of sites of metastases and nephrectomy. This group of patients was of relatively poor performance status and 18 patients (36%) failed to complete one 8-week treatment cycle. Cardiovascular and renal toxicities were less than those seen with intravenous IL-2 schedules but 44% of patients experienced at least one grade III toxicity and only 14% reported less than two grade II toxicities. Plasma levels of elastase-alpha 1 proteinase inhibitor exceeded the normal range in three of seven patients tested before treatment and increased in all seven patients after treatment with IL-2. The same three patients had raised levels of C3a before treatment and in all patients examined, C3a increased after treatment with IL-2. In contrast, plasma prekallikrein concentrations were below normal before treatment and decreased further afterwards. CONCLUSIONS: This study confirms the activity of this regimen in patients of good performance status, with limited sites of disease and in those who are fit for nephrectomy, but also showed that treatment was associated with considerable toxicity. The administration of IL-2 is associated with protease activation which may be a suitable target for pharmacological intervention in attempts to ameliorate toxicity.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Renais/terapia , Elastase de Leucócito , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Complemento C3a/metabolismo , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Humanos , Interferon-alfa/administração & dosagem , Interferon-alfa/efeitos adversos , Interleucina-2/administração & dosagem , Interleucina-2/efeitos adversos , Neoplasias Renais/metabolismo , Masculino , Pessoa de Meia-Idade , Elastase Pancreática/metabolismo , Pré-Calicreína/metabolismo , Qualidade de Vida , Análise de Sobrevida , Resultado do Tratamento , alfa 1-Antitripsina/metabolismoAssuntos
Adenocarcinoma/terapia , Neoplasias Colorretais/terapia , Adenocarcinoma/secundário , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimioterapia Adjuvante , Neoplasias Colorretais/patologia , Terapia Combinada , Fluoruracila/administração & dosagem , Hepatectomia , Humanos , Interferon-alfa/uso terapêutico , Neoplasias Hepáticas/secundário , Neoplasias Hepáticas/terapia , Masculino , Pessoa de Meia-Idade , Mitomicina/administração & dosagemRESUMO
A small pre-treatment 'priming' dose of cyclophosphamide will reduce gut damage due to high dose i.v. melphalan in mice and sheep but efforts to demonstrate this effect in man have been hampered by difficulty in the measurement of gut damage. We have evaluated the 51CR EDTA absorption test, a new method for measuring intestinal permeability, as a means of assessing damage due to high dose melphalan. The test was reliable, with a narrow normal range, easy to use and well tolerated. It detected an increase in intestinal permeability after high dose melphalan with a maximum occurring between 9 and 15 days after treatment and subsequently returning to normal. It was shown in 19 patients that a pre-treatment dose of cyclophosphamide was capable of significantly reducing the abnormalities in intestinal permeability which resulted from high dose melphalan.
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Ciclofosfamida/uso terapêutico , Melfalan/efeitos adversos , Adulto , Transplante de Medula Óssea , Radioisótopos de Cromo , Relação Dose-Resposta a Droga , Ácido Edético/metabolismo , Feminino , Humanos , Absorção Intestinal/efeitos dos fármacos , Enteropatias/prevenção & controle , Mucosa Intestinal/efeitos dos fármacos , Masculino , Melfalan/administração & dosagem , Melfalan/uso terapêutico , Pessoa de Meia-Idade , Neoplasias/tratamento farmacológico , Fatores de TempoAssuntos
Antineoplásicos/farmacologia , Técnicas Citológicas/normas , Avaliação Pré-Clínica de Medicamentos/métodos , Neoplasias/patologia , Bioensaio , Divisão Celular , Sobrevivência Celular , Células Cultivadas , Células Clonais , Avaliação de Medicamentos , Avaliação Pré-Clínica de Medicamentos/normas , Resistência a Medicamentos , Humanos , Modelos Biológicos , Neoplasias/tratamento farmacológico , Efeitos da RadiaçãoRESUMO
Human melanoma xenografts in immune-deprived mice have been used to assess the value of the agar diffusion chamber for chemosensitivity testing. Tumor cells were treated with melphalan, Adriamycin, or methyl trans-1-(2-chloroethyl)-3-(4-methylcyclohexyl)-1-nitrosourea either as solid tumors growing in mice or as suspensions in agar in i.p. diffusion chambers. Survival of clonogenic human tumor cells was measured by the agar diffusion chamber assay in both cases. Cell survival curves were log-linear for treatment of tumor cells in vivo or in the chambers. For melphalan the slopes of survival curves were significantly greater for treatment in the chambers than as solid tumors in vivo, but for methyl trans-1-(2-chloroethyl(-3-(4-methylcyclohexyl)-1-nitrosourea or Adriamycin, they were indistinguishable. Experiments with [14C]melphalan showed that the levels of drug achieved were less inside the diffusion chambers than in the tumors in vivo so that the sensitivity of tumor cells to melphalan was much greater when they were treated in chambers. The differences in drug exposure and in cellular chemosensitivity between chambers and tumors suggest caution in the interpretation of drug testing using this system, but the log-linear nature of the dose-response curves is an important feature which may be useful in the eventual development of optimal chemosensitivity testing systems.