[Quality assurance of a virtual simulation software: application to IMAgo and SIMAgo (ISOgray)]

PURPOSE

Virtual simulation process is often used to prepare three dimensional conformal radiation therapy treatments. As the quality of the treatment is widely dependent on this step, it is mandatory to perform extensive controls on this software before clinical use. The tests presented in this work have been carried out on the treatment planning system ISOgray (DOSIsoft), including the delineation module IMAgo and the virtual simulation module SIMAgo.

MATERIAL AND METHODS

According to our experience, the most relevant controls of international protocols have been selected. These tests mainly focused on measuring and delineation tools, virtual simulation functionalities, and have been performed with three phantoms: the Quasar Multi-Purpose Body Phantom, the Quasar MLC Beam Geometry Phantom (Modus Medical Devices Inc.) and a phantom developed at Hospital Tenon.

RESULTS

No major issues have been identified while performing the tests. These controls have emphasized the necessity for the user to consider with a critical eye the results displayed by a virtual simulation software. The contrast of visualisation, the slice thickness, the calculation and display mode of 3D structures used by the software are many factors of uncertainties.

CONCLUSION

A virtual simulation software quality assurance procedure has been written and applied on a set of CT images. Similar tests have to be performed periodically and at minimum at each change of major version.

A systematic review of environmental correlates of obesity-related dietary behaviors in youth

There is increasing interest in the role the environment plays in shaping the dietary behavior of youth, particularly in the context of obesity prevention. An overview of environmental factors associated with obesity-related dietary behaviors among youth is needed to inform the development of interventions. A systematic review of observational studies on environmental correlates of energy, fat, fruit/vegetable, snack/fast food and soft drink intakes in children (4-12 years) and adolescents (13-18 years) was conducted. The results were summarized using the analysis grid for environments linked to obesity. The 58 papers reviewed mostly focused on sociocultural and economical-environmental factors at the household level. The most consistent associations were found between parental intake and children's fat, fruit/vegetable intakes, parent and sibling intake with adolescent's energy and fat intakes and parental education with adolescent's fruit/vegetable intake. A less consistent but positive association was found for availability and accessibility on children's fruit/vegetable intake. Environmental factors are predominantly studied at the household level and focus on sociocultural and economic aspects. Most consistent associations were found for parental influences (parental intake and education). More studies examining environmental factors using longitudinal study designs and validated measures are needed for solid evidence to inform interventions.

Perceived parenting style and practices and the consumption of sugar-sweetened beverages by adolescents

The purpose of this study was to investigate whether perceived parenting practices and parenting style dimensions (strictness and involvement) are associated with adolescents' consumption of sugar-sweetened beverages. In this cross-sectional study, secondary school students (n = 383, mean age 13.5 years) completed a self-administered questionnaire on their consumption of sugar-sweetened beverages, attitude, social influences, self-efficacy, habit strength, food-related parenting practices and the general parenting style dimensions of 'strictness' and 'involvement'. Data were analyzed using multiple linear regression analyses. More restrictive parenting practices were associated with lower consumption of sugar-sweetened beverages (beta = -38.0 ml; 95% CI = -48.1, -28.0). This association was highly mediated ( approximately 55%) by attitude, self-efficacy and modeling from parents. Nevertheless, a significant direct effect remained (beta = -17.1 ml; 95% CI = -27.2, -6.90). Interactions between perceived parenting style and parenting practices showed that the association between parenting practices and sugar-sweetened beverage consumption was stronger among adolescents who perceived their parents as being moderately strict and highly involved. Parents influence their children's sugar-sweetened beverage consumption and should therefore be involved in interventions aimed at changing dietary behaviors. Interventions aimed at the promotion of healthy parenting practices will improve when they are tailored to the general parenting style of the participants.

Congenital amegakaryocytic thrombocytopenia--report of a new c-mpl gene missense mutation

A 44-month old girl with congenital amegakaryocytic thrombocytopenia, already with pancytopenia, underwent an unrelated allogeneic cord blood transplantation with recovery of normal blood cell counts. The patient was a compound heterozygote for two c-mpl missense mutations inherited from both parents, one of them, a G578A exon 4 mutation leading to a cysteine to tyrosine replacement of codon 193, previously unreported.

Environmental correlates of physical activity in youth - a review and update

Obesogenic environments are thought to underlie the increased obesity prevalence observed in youth during the past decades. Understanding the environmental factors that are associated with physical activity (PA) in youth is needed to better inform the development of effective intervention strategies attempting to halt the obesity epidemic. We conducted a systematic semi-quantitative review of 150 studies on environmental correlates of youth PA published in the past 25 years. The ANalysis Grid for Environments Linked to Obesity (ANGELO) framework was used to classify the environmental correlates studied. Most studies retrieved used cross-sectional designs and subjective measures of environmental factors and PA. Variables of the home and school environments were especially associated with children's PA. Most consistent positive correlates of PA were father's PA, time spent outdoors and school PA-related policies (in children), and support from significant others, mother's education level, family income, and non-vocational school attendance (in adolescents). Low crime incidence (in adolescents) was characteristic of the neighbourhood environment associated with higher PA. Convincing evidence of an important role for many other environmental factors was, however, not found. Further research should aim at longitudinal and intervention studies, and use more objective measures of PA and its potential (environmental) determinants.

Spatial inhomogeneity of common carotid artery intima-media is increased in dialysis patients

BACKGROUND

Structural abnormalities of the common carotid artery (CCA), as assessed by ultrasound techniques, are related to cardiovascular outcome in dialysis patients. An increased intima media thickness (IMT) of the CCA may both represent a reaction to a haemodynamic burden as well as atherosclerosis. With a new ultrasound technique CCA-IMT and IMT-inhomogeneity, a novel parameter of spatial variance of the IMT, were measured and related to traditional and non-traditional risk factors.

METHODS

In a cross-sectional study, we included 134 dialysis patients, aged 61+/-13 years (103 on haemodialysis, 31 on peritoneal dialysis) and 41 controls, aged 60+/-8 years. Age, sex, pulse pressure, diabetes, prevalent cardiovascular disease (CVD) and height were included in the basic multiregression analysis. Ultrasound examination of the CCA was performed. We also measured serum fetuin-A, high-sensitivity C-reactive protein (hsCRP), antibodies to oxidized low density lipoproteins (anti-oxLDL antibodies), calcium, phosphate, albumin and parathyroid hormone.

RESULTS

Compared with controls, dialysis patients had a greater CCA-IMT (670 microm vs 590+/-10 microm; P=0.002) and a greater CCA-IMT inhomogeneity (11.0 vs 8.1%; P=0.013). Dialysis patients with CVD had a greater CCA-IMT (734 microm vs 631 microm; P=0.001) and IMT-inhomogeneity (13.2 vs 9.7; P=0.008) compared with patients without CVD. IMT-inhomogeneity strongly correlated with IMT (R=0.65, P<0.0001). In multiregression analysis, serum fetuin-A and anti-oxLDL antibodies correlated with IMT-inhomogeneity but not with IMT. HsCRP neither correlated with IMT-inhomogeneity nor with IMT.

CONCLUSION

The present study shows that CCA-IMT and IMT-inhomogeneity were increased in dialysis patients compared with controls. Although CCA-IMT and IMT-inhomogeneity are related, the different associations between both measurements and non-traditional risk factors show that they are distinct entities.

Présent et avenir de la radiothérapie guidée par l'image (IGRT) et ses applications possibles dans le traitement des cancers bronchiques

These last years, the new irradiation techniques as the conformal 3D radiotherapy and the IMRT are strongly correlated with the technological developments in radiotherapy. The rigorous definition of the target volume and the organs at risk required by these irradiation techniques, imposed the development of various image guided patient positioning and target tracking techniques. The availability of these imaging systems inside the treatment room has lead to the exploration of performing real-time adaptive radiation therapy. In this paper we present the different image guided radiotherapy (IGRT) techniques and the adaptive radiotherapy (ART) approaches. IGRT developments are focused in the following areas: 1) biological imaging for better definition of tumor volume; 2) 4D imaging for modeling the intra-fraction organ motion; 3) on-board imaging system or imaging devices registered to the treatment machines for inter-fraction patient localization; and 4) treatment planning and delivery schemes incorporating the information derived from the new imaging techniques. As this paper is included in the "Cancer-Radiotherapie" special volume dedicated to the lung cancers, in the description of the different IGRT techniques we try to present the lung tumors applications when this is possible.

Irradiation prophylactique cérébrale dans les cancers bronchopulmonaires non à petites cellules

Prophylactic cranial irradiation (PCI) has become part of the standard treatment in patients with small cell lung cancer (SCLC) in complete remission. Not only does it decrease the risk of brain recurrence by almost 50%, it has a significant positive effect on survival (5.4 percent increase at 3 years). As the prognosis of patients with locally advanced non-small cell lung cancer (NSCLC) has improved with combined modality treatment, brain metastases have also become an important cause of failure (10 to 30%, approaching 50% in certain studies as in SCLC). Survival after treatment of brain metastases is poor and impact on quality of life of patients is important. As in SCLC, 4 randomised evaluating PCI in NSCLC have been carried out in the seventies and early eighties. If 3 out of 4 trials have shown a significant decrease of brain metastases, none of them demonstrated any impact on survival. Thus PCI cannot be recommended as standard treatment in NSCLC, however new trials would be needed.

Energy-saving wastewater treatment systems: formulation of cost functions

Natural interactions between water, soil, atmosphere, plants and microorganisms include physical, chemical and biological processes with decontaminating capacities. Natural or energy-saving wastewater treatment systems utilize these processes and thereby enable a sustainable management in the field of wastewater treatment, offering low investment and operation costs, little or no energy consumption, little and low-skill labor requirements, good landscape integration and excellent feasibility for small settlements, especially when remote from centralized sewer systems. The objective of this work is the development of cost functions for investment and operation of energy-saving wastewater treatment technologies. Cost functions are essential for making cost estimations based on a very reduced number of variables. The latter are easily identified and quantified and have a direct bearing on the costs in question. The formulated investment and operation cost functions follow a power law, and the costs decrease with the increase of the population served. The different energy-saving wastewater treatment systems serving small population settlements, between 50 p.e. and 250 p.e., present associated investment costs varying from 400 Euro/p.e. to 200 Euro/p.e. and annual operation costs in the range of 70 Euro/p.e. to 20 Euro/p.e., respectively.

[Small cell lung cancer (CPC). Management of patients presenting with limited stage small cell carcinoma of the lung]

Small cell carcinomas represent less than 20% of all lung cancer. Only a third of these patients present with limited stage disease. Treatment is based on a combination of chemotherapy and radiotherapy including a platinum salt with or without another drug. Conformational thoracic radiotherapy is administered either classically fractionated or in an accelerated form. Prophylactic cranial irradiation is indicated in patients with a good response. An improvement in outcomes has been obtained with this regimen. Even in limited stage disease 5 year survival remains about 25% in the best series. The majority of patients will relapse and the risk of cerebral metastases is particularly high, reaching nearly 50% at 2 years even in patients with a complete response. Prophylactic cranial irradiation should be part of the standard management of patients with a complete response on the basis of a meta analysis showing a 5% increase in survival at three years. Even though combination treatments have improved survival, a number of questions remain that should stimulate further clinical trials to establish the optimum regimes of chemotherapy and radiotherapy and the optimum strategies for combining the two. In addition the potential role of targeted therapy in selected patients must be examined.

Cancers bronchiques : la radiothérapie prophylactique des aires ganglionnaires a-t-elle encore une place ?

The use of conformal radiotherapy in lung cancer has considerably evolved with the advent of improved staging technologies and methods of radiation delivery. Patients with limited disease, inoperable for medical reasons, may be treated with conformal radiotherapy alone; patients with more advanced disease are treated with combined chemo-radiotherapy. If local control may be improved by radiotherapy dose escalation according to several studies, toxicity and more particularly pulmonary toxicity seems to be related to radiation volume. Thus the use of elective nodal irradiation is being questioned. Data for early stage (stage I) non-small-cell lung cancer treated with conformal radiotherapy or stereotactic hypofractionated radiotherapy strongly supports the use of smaller fields that do not incorporate elective nodal regions; local control and survival rates approach those of surgical series. In locally advanced non-small cell lung cancer, eliminating elective nodal irradiation allows to maximize tumor dose and minimize normal tissue toxicity in combined modality treatments; results are encouraging. The use of staging modalities such as positron emission tomography and eventually oesophageal ultrasonography is increasing, allowing to encompass the tumor volume with more accuracy. Several studies have confirmed that involved-field irradiation results into a regional nodal rate of less than 10%. Further larger-scale studies would be needed to definitely establish "no elective nodal irradiation" as a standard in non-small cell lung cancer. There are very few data concerning small cell lung cancer.

Diagnosis of respiratory bronchiolitis associated interstitial lung disease

BACKGROUND

Respiratory Bronchiolitis (RB), described by Niewoehner et al in 1974, is a common finding in heavy smokers and is characterised by the presence of pigmented macrophages within respiratory bronchioles and adjacent alveoli. In the 1980s, Myers et al described RB associated with interstitial lung disease (RBILD), which is a rare entity expressed as an amplified respiratory bronchiolitis in response to cigarette smoke.

METHODS

The authors studied a group of 8 patients with biopsy-proven RBILD diagnosed within the last five years, and assessed epidemiological data, clinical and imaging features, lung function tests, bronchoalveolar lavage findings, therapeutic approaches and clinical evolution.

RESULTS AND CONCLUSIONS

The most difficult differential diagnosis is between RBILD and Desquamative Interstitial Pneumonia (DIP), which seems to suggest that these disorders are either end of the same spectrum, although the authors claim that there are some clinical, morphological and prognostic distinctions. The diagnosis of RBILD requires an appropriate clinical setting (including smoking habits), characteristic image findings (like ground glass shadowing and centrilobular nodules), and Bronchoalveolar Lavage (BAL) data to exclude other diagnosis. Pathological confirmation may also be important, not only to exclude more adverse interstitial lung disease, such as idiopathic pulmonary fibrosis, but also, as in the eight cases presented, to illustrate some specific features such as the prevalence of lymphocytosis in BAL.

[Image registration for radiation therapy: Practical aspects and quality control]

The development of conformal radiotherapy techniques (CRT) and intensity modulated CRT requires an accurate delineation of target structures and organs at risk. Thus, additional information provided by anatomical and/or functional imaging modalities can be used for volume of interest determination combined with traditionally used Computed Tomography imaging (CT): for instance, functional or morphological Magnetic Resonance Imaging (f MRI or m MRI) or Positron Emission Tomography (PET). A prerequisite to the simultaneous use of this information is image registration. Due to the differences between the images and the information they provide, a quality control of image registration process for radiotherapy is mandatory. The purpose of this article is to present the difficulties in implementing such controls and to show the necessity for a clinical validation on patient's images. The last part of this work presents the possible interest in using f MRI to help radio-oncologists in the treatment planning for gliomas associated to image coregistration and quality control considerations.

Differences in measured and self-reported height and weight in Dutch adolescents

BACKGROUND/AIMS

Monitoring overweight prevalence and its trends in Dutch youth is frequently based on self-reported data. The validity of self-reported data especially in young adolescents is not sufficiently known. The purpose of this study is to study the validity of self-reported height and weight in 12- to 13-year-olds, to identify sociodemographic correlates and to explore whether correction factors can be developed to estimate the prevalence of overweight in youth.

METHODS

5,525 12- to 13-year-old pupils in the Rotterdam area filled in a confidential questionnaire on health topics, including their height and weight. In a sub-sample of 499 pupils both self-reported and measured height and weight were available.

RESULTS

Self-reported data led to a considerable underestimation of Body Mass Index and consequently the prevalence of overweight. Underestimation was higher in pupils who regarded themselves as more fat, were of non-Dutch origin and in lower education levels.

CONCLUSION

Self-reported height and weight appeared to be inappropriate to estimate the overweight prevalence in 12- to 13-year-olds, unless the figures were adjusted. Using adjusted self-reported BMI on an individual level is questionable. Actual measurements of height and weight are necessary to draw up valid correction formulas in new samples.

[Thoracic adenoid cystic carcinomas]

Adenoid cystic carcinomas in the trachea are rare, but represent around 40% of all tracheal tumours. Other intrathoracic localisations include the carena or proximal airways. Adenoid cystic carcinoma's growth rate is slow so that it is frequently diagnosed at an advanced stage. Pathological identification may be difficult. Treatment in limited tumours is based upon surgical resection often combined to radiotherapy because of close surgical margins. Radiotherapy dose may vary between 45 and 65 Gy according to margins status. Five-year survival rates of 65-80% have been reported after surgery or surgery and postoperative radiotherapy. Among inoperable patients treated with exclusive radiotherapy for tracheal tumours (including adenoid cystic but also squamous cell carcinomas of poorer prognosis), the recommended delivered dose should be over 60 Gy. Five-year survival rate in these very heterogeneous series may vary between 12 and 27%. Local or metastatic recurrences may occur very lately. They are considered chemo-resistant and targeted therapies may prove to be effective in the future.

The metabolic syndrome, cardiopulmonary fitness, and subcutaneous trunk fat as independent determinants of arterial stiffness: the Amsterdam Growth and Health Longitudinal Study

BACKGROUND

The mechanisms that link the metabolic syndrome to increased cardiovascular risk are incompletely understood, especially in young people. We therefore examined whether the metabolic syndrome was associated with arterial stiffness and whether any such associations were independent of cardiopulmonary fitness and subcutaneous trunk fat.

METHODS

Cross-sectional analyses of data on 364 men and women aged 36 years from the Amsterdam Growth and Health Longitudinal Study (ninth follow-up measurement, year 2000). The prevalence of the metabolic syndrome was defined by a slightly modified National Cholesterol Education Program (NCEP) definition. Arterial stiffness was ultrasonically estimated by distensibility and compliance of the carotid, femoral, and brachial arteries and by the carotid elastic modulus.

RESULTS

The prevalence of the metabolic syndrome in this young adult population was 18.3% in men and 3.2% in women. Individuals with the syndrome compared with individuals without risk factors had 11.2% and 17.0% less distensibility and 9.0% and 18.2% less compliance of the carotid and femoral arteries, respectively, and 15.9% higher carotid elastic modulus. After adjustment for cardiopulmonary fitness and subcutaneous trunk fat, the metabolic syndrome remained significantly associated with stiffness of the carotid but not the femoral artery. In addition, poor cardiopulmonary fitness and high subcutaneous trunk fat were associated with arterial stiffness, and this was independent of the metabolic syndrome.

CONCLUSIONS

A modified NCEP definition of the metabolic syndrome identified young individuals with increased arterial stiffness. The mechanisms that link the metabolic syndrome, poor cardiopulmonary fitness, and high subcutaneous trunk fat to greater arterial stiffness overlap but are partly independent of each other.

[Chorionicity and adverse perinatal outcome]

OBJECTIVE

Considering the highest rate of morbidity and mortality in diamniotic monochorionic twins, the authors evaluated and compared the adverse obstetric and perinatal outcome in twin pregnancies according to chorionicity.

PATIENTS AND METHODS

A retrospective study was conducted in all twin deliveries that occurred in the Obstetric Unit of Maternidade Bissaya-Barreto, for a period of tree years (from the 1st of January 1999 until the 31st of December 2001). From de 140 diamniotic twin pregnancies studied, we considered two groups according to the chorionicity: monochorionic and dichorionic. We compared multiple parameters as, epidemiologic data, adverse obstetric outcome, gestacional delivery age, type of delivery and the morbidity, the mortality and the follow-up of the newborn. The statistic tests used were the X2 and the t student.

RESULTS

From the 140 twin pregnancies included in the study, 66% (92 cases) presented dichorionic placentation and 34% (48 cases) were monochorionic. In the group of monochorionic pregnancies, we observed highly difference related to pathology of amniotic fluid (14.5% vs 2.2%), discordant fetal growth (41.6% vs 22.8%) and rate of preterm delivery (66.6% vs 32.6%). Related to the newborn we verified that they had a lower average birth weight (1988g vs 2295g), a highly rate of weight discordancy (23% vs 15.3%), intraventricular haemorrhage (2.2% vs 0%) and IUGR (6.6% vs 1.6%), statistically significant in the monochorionic group. Also the perinatal mortality rate was significantly higher in the monochorionic pregnancies (93.7 per thousand vs 21.7 per thousand).

CONCLUSION

The high rate of morbidity and mortality related to the monochorionic twin pregnancies, implies the need of a correct identification of the type of chorionicity and also a high standard of prenatal surveillance in prenatal specialised health centers.

Theory, evidence and Intervention Mapping to improve behavior nutrition and physical activity interventions

BACKGROUND: The present paper intends to contribute to the debate on the usefulness and barriers in applying theories in diet and physical activity behavior-change interventions. DISCUSSION: Since behavior theory is a reflection of the compiled evidence of behavior research, theory is the only foothold we have for the development of behavioral nutrition and physical activity interventions. Application of theory should improve the effectiveness of interventions. However, some of the theories we use lack a strong empirical foundation, and the available theories are not always used in the most effective way. Furthermore, many of the commonly-used theories provide at best information on what needs to be changed to promote healthy behavior, but not on how changes can be induced. Finally, many theories explain behavioral intentions or motivation rather well, but are less well-suited to explaining or predicting actual behavior or behavior change.For more effective interventions, behavior change theory needs to be further developed in stronger research designs and such change-theory should especially focus on how to promote action rather than mere motivation. Since voluntary behavior change requires motivation, ability as well as the opportunity to change, further development of behavior change theory should incorporate environmental change strategies. CONCLUSION: Intervention Mapping may help to further improve the application of theories in nutrition and physical activity behavior change.

Regional body composition as a determinant of arterial stiffness in the elderly: The Hoorn Study

OBJECTIVE

To estimate the relation of precisely measured regional body composition with peripheral and central arterial stiffness in the elderly.

METHODS

We investigated 648 participants (mean age 69.0 +/- 6.0 years) of the Hoorn Study, a population-based cohort study. Trunk fat, leg fat, trunk lean and leg lean mass were distinguished by dual-energy X-ray absorptiometry. We used ultrasound to measure the distensibility and compliance of the carotid, femoral and brachial arteries, and carotid Young's elastic modulus, as estimates of peripheral stiffness. As estimates of central stiffness we measured carotid-femoral transit time, aortic augmentation index and systemic arterial compliance.

RESULTS

After adjustment for sex, age, height, mean arterial pressure, leg lean and leg fat mass, a larger trunk fat mass was consistently associated with higher peripheral arterial stiffness (standardized beta (beta) of mean Z-scores of all three large arteries -0.24, P < 0.001). In contrast, larger leg fat mass (beta = 0.15, P = 0.009) and leg lean mass (beta = 0.09, P = 0.20) were associated with lower peripheral arterial stiffness. Trunk or leg fat mass were not associated with central arterial stiffness. Leg lean mass, however, was consistently associated with lower central arterial stiffness (beta = 0.29, P < 0.001).

CONCLUSIONS

Trunk fat mass may have adverse effects on peripheral, but not on central arterial stiffness, while leg fat was not harmful and may have a slight protective effect. Larger leg lean mass was the most important determinant of lower central arterial stiffness. These results provide a pathophysiological framework to explain not only the higher cardiovascular risk in individuals with larger trunk fat mass, but also the reduced cardiovascular risk in individuals with larger leg lean and fat mass.

Development of Fatness, Fitness, and Lifestyle From Adolescence to the Age of 36 Years

BACKGROUND

Among young adults, the metabolic syndrome is an increasingly frequent risk factor for cardiovascular disease. Its determinants are, however, incompletely understood. We investigated the time course, from adolescence (age, 13 years) to young adulthood (age, 36 years), of important potential determinants (body fatness and fat distribution, cardiopulmonary fitness, and lifestyle) in 364 individuals (189 women).

METHODS

Data were derived from the Amsterdam Growth and Health Longitudinal Study and analyzed with the use of generalized estimating equations.

RESULTS

The prevalence of the metabolic syndrome at the age of 36 years, as identified with a modified National Cholesterol Education Program definition of the syndrome, was 10.4%. Subjects with the metabolic syndrome at the age of 36 years, compared with those without the syndrome, had (from adolescence to the age of 36 years) the following: (1) a more marked increase in total body fatness and in subcutaneous trunk fat; (2) a more marked decrease in cardiopulmonary fitness levels; (3) a more marked increase in physical activities of light-to-moderate intensity, but a more marked decrease in hard physical activities; (4) a trend toward a higher energy intake throughout the years; and (5) a decreased likelihood of drinking alcoholic beverages.

CONCLUSIONS

Fatness, fitness, and lifestyle are important determinants of the metabolic syndrome in young adults. More important, these associations were independent of each other and, therefore, represent separate potential targets for the prevention of the metabolic syndrome. Our study further suggests that intervening early in life (eg, in the period of transition from adolescence to adulthood) may be a fruitful area for prevention of the metabolic syndrome.

Cardiorespiratory Fitness, Physical Activity, and Arterial Stiffness

Poor cardiorespiratory fitness and low physical activity have been identified as determinants of greater arterial stiffness, a mechanism that can partially explain the association of both variables with increased cardiovascular disease. However, the nature of these associations are not clear because cardiorespiratory fitness and physical activity can both mediate and confound the associations of one another with arterial stiffness. This issue was therefore examined in a population-based cohort of young adults. Subjects included 405 young men and women participating in an ongoing longitudinal study, the Northern Ireland Young Hearts Project. Pulse wave velocity was used to determine arterial stiffness in 2 arterial segments (aortoiliac and aortodorsalis pedis) using a noninvasive optical method. Cardiovascular fitness was estimated with a submaximal cycle test of physical work capacity and physical activity was estimated using a modified Baecke questionnaire. Associations were investigated with the use of multiple linear regression models with adjustment for potential confounders and/or intermediate variables. Cardiorespiratory fitness and sports-related physical activity (but not leisure- and work-related physical activity) were inversely associated with arterial stiffness in young adults. The associations between sports-related physical activity and arterial stiffness were strongly mediated by cardiorespiratory fitness, whereas physical activity levels did not disturb the associations between cardiopulmonary fitness and arterial stiffness. These findings suggest that arterial stiffness-related benefits of exercise are most likely to accrue if exercise prescription in young adults targets improvements in cardiorespiratory fitness.

Type 2 diabetes is associated with impaired endothelium-dependent, flow-mediated dilation, but impaired glucose metabolism is not; The Hoorn Study

BACKGROUND

Type 2 diabetes (DM2) and impaired glucose metabolism (IGM) are associated with an increased cardiovascular disease risk. Impaired endothelial synthesis of nitric oxide (NO) is an important feature of atherothrombosis and can be estimated from endothelium-dependent flow-mediated dilation (FMD). It is controversial whether or not FMD is impaired in DM2 and IGM. We investigated this issue in a population-based setting.

METHODS AND RESULTS

In the study population (n = 650; 246 with normal glucose metabolism (NGM), 135 with IGM and 269 with DM2; mean age: 67.6 years), FMD and endothelium-independent nitroglycerine-mediated dilation (NMD) were ultrasonically estimated from the brachial artery and expressed as the absolute change in diameter in mm. The increase in diameter (mean +/- standard deviation) in NGM, IGM and DM2 was 0.19 +/- 0.15, 0.19 +/- 0.18 and 0.13 +/- 0.17 MD and 0.45 +/- 0.21, 0.43 +/- 0.24 and 0.45 +/- 0.25 for NMD. After adjustment for age, sex, baseline diameter and percentage increase in peak systolic velocity, DM2, as compared to NGM, remained associated with impaired FMD (regression coefficient beta (95%CI)) as compared to NGM, -0.06 mm (-0.09 to -0.03). IGM was not associated with impaired FMD (beta, 0.01 mm (-0.02 to 0.04)). Additional adjustment for conventional cardiovascular risk factors did not alter these associations. Hyperglycemia or hyperinsulinemia explained 2% of the association between DM2 and FMD. NMD was not associated with glucose tolerance.

CONCLUSIONS

This study shows that DM2 is independently associated with impaired FMD. Hyperglycemia and hyperinsulinemia contribute minimally to this association. Impaired FMD may therefore, in part, explain the increased cardiovascular disease risk in DM2, whereas the normal FMD in IGM suggests that other forms of endothelial dysfunction are important in explaining the increased cardiovascular disease risk in IGM.

Central fat mass versus peripheral fat and lean mass: opposite (adverse versus favorable) associations with arterial stiffness? The Amsterdam Growth and Health Longitudinal Study

Central and peripheral fatness seem to confer opposite (i.e. adverse vs. protective) effects on cardiovascular risk, but how this occurs is not clear. In addition, the role of peripheral lean mass needs to be elucidated. We therefore investigated, in 336 (175 women) 36-yr-old and apparently healthy adults, the relationship between trunk fat, peripheral fat, and peripheral lean mass on the one hand, and estimates of stiffness of three large arteries on the other. Body composition was assessed by dual-energy x-ray absorptiometry. Arterial properties were assessed by ultrasound imaging. We found that 1) trunk fat was positively (i.e. adversely) associated with stiffness of the carotid and femoral arteries, whereas peripheral fat was inversely (i.e. favorably) associated with stiffness of the brachial and the carotido-femoral segment; 2) peripheral lean mass was positively associated with arterial diameter and carotid compliance and inversely associated with stiffness of the carotido-femoral segment; and 3) after adjustment for the other body composition variables, the above-mentioned associations remained, but peripheral fat in addition became, if anything, favorably associated with stiffness of the femoral artery. We conclude that trunk fat is adversely associated with large artery stiffness, whereas some degree of protection is conferred by peripheral fat and lean mass.

Longitudinal changes in .VO2max: associations with carotid IMT and arterial stiffness

PURPOSE

High levels of cardiorespiratory fitness (.VO2max) are associated with reduced risk of cardiovascular morbidity and mortality. However, little is known to what extent longitudinal changes in .VO2max affect arterial wall thickness and stiffness, i.e., two major risk factors for cardiovascular disease. We therefore investigated the relationship between changes in .VO2max from adolescence (13-16 yr) to adulthood (age 36) and from young adulthood (21-32 yr) to age 36, and carotid intima-media thickness (IMT) and stiffness of the carotid, femoral, and brachial arteries, at age 36.

METHODS

Analyses of changes in .VO2max from adolescence to age 36 consisted of 154 subjects (79 women), and from young adulthood to age 36 consisted of a subpopulation of 118 subjects (62 women). Throughout the years, .VO2max was measured directly with a maximal running test on a treadmill. When the subjects had the mean age of 36, carotid IMT and large artery stiffness (distensibility and compliance coefficients) were assessed noninvasively by ultrasound imaging methods.

RESULTS

Longitudinal changes in .VO2max were not significantly associated with carotid IMT. Changes in .VO2max were inversely and significantly associated with large artery stiffness. These associations were not uniform throughout the arterial tree, being stronger and independent of changes in other risk factors in the muscular (brachial and femoral) arteries but dependent on and possibly mediated by concomitant changes in HDL cholesterol and body weight in the elastic carotid artery.

CONCLUSION

Increases in .VO2max that occur from adolescence up to age 36 are associated with less arterial stiffness. Improving .VO2max by increasing physical activity levels may therefore contribute to a reduction in mortality from cardiovascular disease through decreasing arterial stiffness.

Birthweight and arterial stiffness and blood pressure in adulthood--Results from the Amsterdam Growth and Health Longitudinal Study

BACKGROUND

The association between low birthweight and increased blood pressure in later life has repeatedly been confirmed. Increased arterial stiffness may be an underlying mechanism for this phenomenon. This study investigated whether birthweight was related to blood pressure and local and regional arterial stiffness.

METHODS

In 281 subjects (161 women), with a mean age of 36, blood pressure was measured. The diameter, distension, and local pulse pressure of three large arteries were measured simultaneously using ultrasound imaging. Local and regional arterial compliance and distensibility were calculated. Information on birthweight was retrieved with a questionnaire.

RESULTS

Linear regression analyses showed a 3.3 mmHg lower systolic blood pressure (SBP) and a 1.8 mmHg lower diastolic blood pressure (DBP), per 1kg higher birthweight. These associations were statistically significant after adjustment for adult weight. Birthweight was significantly and positively related to carotid arterial compliance (P = 0.050), but less so to brachial (P = 0.114) and femoral arterial compliance (P = 0.058). However, after adjustment for adult height, the strength of these associations decreased. Birthweight was not related to arterial distensibility. The association between birthweight and arterial compliance could only partly explain the association between birthweight and blood pressure.

CONCLUSIONS

Lower birthweight is related to increased blood pressure, and increased arterial stiffness. However, the latter relationship can only partly explain the association between birthweight and blood pressure. Therefore, mechanisms other than arterial stiffness contribute to the birthweight-blood pressure relationship.

Current and adolescent body fatness and fat distribution

OBJECTIVE

Body fat and its distribution are determinants of cardiovascular disease but the underlying mechanisms of these adverse effects are poorly understood. We therefore investigated (1) the cross-sectional relationship between estimates of body fatness and its distribution on the one hand and carotid atherosclerosis and stiffness of the carotid, femoral and brachial arteries and the carotido-femoral segment on the other (336 subjects, 175 women); (2) the relationship between estimates of body fatness and its distribution during adolescence (13-16 years) and the same arterial properties at age 36- prospective analyses (subpopulation of 159 subjects, 84 girls).

DESIGN

Cross-sectional and prospective analyses within an ongoing observational longitudinal study: The Amsterdam Growth and Health Longitudinal Study.

METHODS

Body fatness and its distribution were assessed by anthropometry and dual-energy X-ray absorptiometry (DXA); arterial properties were assessed non-invasively by ultrasound imaging.

RESULTS

Total adiposity and, in men, truncal subcutaneous fat accumulation during adolescence, were positively and independently associated with carotid intima-media thickness at age 36, a pre-clinical indicator of atherosclerosis. Adolescent truncal subcutaneous fat accumulation but not total adiposity was associated with increased arterial stiffness at age 36. At age 36, both abdominal and truncal subcutaneous fat were independently associated with arterial stiffness, while the associations between total adiposity and arterial stiffness appeared to be mediated by other cardiovascular risk factors.

CONCLUSIONS

Body fatness and body fat distribution are associated with large artery structural and functional properties at age 36 and the roots of these associations may already be present in adolescence.

Experience with enoxaparin in patients with mechanical heart valves who must withhold acenocumarol

OBJECTIVES

To evaluate the incidence of thromboembolic and haemorrhagic events in a cohort of patients with mechanical heart valves who had to withhold acenocumarol and were treated with enoxaparin.

DESIGN

Observational prospective study.

SETTING

In hospital; after discharge, and follow up by telephone call.

PATIENTS AND METHODS

All consecutive patients with mechanical heart valves admitted to the authors' hospital between May 1999 and January 2002 who had to interrupt treatment with acenocumarol and were treated with enoxaparin as an alternative to other methods were enrolled. In each patient, the following characteristics were prospectively determined: the reason for interrupting acenocumarol, demographic data, estimated global risk for thromboembolic events, international normalised ratio before starting enoxaparin treatment, number of days taking enoxaparin, and mean level of anti-Xa activity during treatment. All patients were followed up through clinical history during the hospitalisation and by telephone after discharge to detect thromboembolic events.

MAIN OUTCOME MEASURE

Presence of thromboembolic or haemorrhagic events.

RESULTS

82 patients were identified and followed up for a mean of 2.8 months (range 1.5-3.5 months) after discharge. 61 of them (74%) had one or more associated thromboembolic risk factors. Acenocumarol was interrupted (to perform an invasive procedure in 74 patients and because of haemorrhagic complication in 8) an average of 11.2 days (range 3-40 days). Most patients received the standard enoxaparin dose (1 mg/kg at 12 hour intervals). Mean (SD) anti-Xa activity was 0.58 (0.3) IU/ml (median 0.51). There were 8 minor and 1 major bleeding events during enoxaparin treatment. No thromboembolic complications were clinically detected during hospitalisation or during follow up (95% confidence interval 0% to 3.6%).

CONCLUSIONS

Enoxaparin may be an effective and relatively safe substitute anticoagulant for patients with mechanical heart valves who must withhold acenocumarol.

Current and adolescent levels of cardiopulmonary fitness are related to large artery properties at age 36: the Amsterdam Growth and Health Longitudinal Study

BACKGROUND

High levels of cardiopulmonary fitness (VO2max) are associated with reduced risk of cardiovascular morbidity and mortality, but little is known to what extent this is related to the effects of cardiopulmonary fitness on atherosclerosis and arterial stiffness. Moreover, the time course of these relationships needs to be elucidated. We sought to investigate (i) the cross-sectional relationship between VO2max and carotid atherosclerosis and carotid and femoral arterial stiffness at age 36, as well as (ii) the relationship between VO2max during adolescence (13-16 years) and the same arterial properties at age 36 (prospective analyses).

DESIGN

Cross-sectional analyses consisted of 351 subjects (183 women) and the prospective analyses of a subpopulation of 154 subjects (79 girls). Arterial properties were assessed noninvasively by ultrasound imaging; VO2max was measured with a maximal running text on a treadmill with direct measurements of oxygen uptake.

RESULTS

After adjustment for confounding by other known risk factors, current and adolescent levels of VO2max were independently associated with carotid intima-media thickness (beta = -0.288, P = 0.004 and beta = -0.381, P = 0.012) in men, and with the diameter of the femoral artery (beta = 0.375, P < 0.001 and beta = 0.252, P = 0.026, respectively) in both sexes. Current levels of VO2max were positively associated with the compliance of the carotid and the femoral arteries (beta = 0.186, P = 0.023 and beta = 0.183, P = 0.033, respectively), and with the distensibility of the carotid (beta = 0.162, P = 0.047) but not the femoral artery.

CONCLUSION

We conclude that cardiopulmonary fitness is associated with large artery properties at age 36, and that the roots of this association may already be present in adolescence.

International approaches to the prescription of long-term oxygen therapy

While there is broad agreement about who should receive long-term oxygen therapy (LTOT), there is little information available on how clinicians should decide on the oxygen prescription itself, at rest, during sleep and during exercise. The authors describe the results of an international survey that was undertaken to compare how respirologists prescribed oxygen. A questionnaire was sent to 100 respirologists in each of seven countries. The questionnaire identified whether resting flow rates were derived in a standard manner or by individualized patient testing. Test targets were ascertained for rest, exercise and sleep, as was the percentage of time that each test target had to reach for the test to be accepted. The majority of respondents individualized the oxygen prescription at rest (81%). Resting arterial oxygen saturation (Sa,O2) was most commonly targeted at 90-91%. The approach to night prescription varied (p<0.001). Respirologists in Canada and the USA increased the resting Sa,O2 by 1-2 L x min(-1) during sleep, while those in Spain used the resting (awake) flow for the night prescription (62%). Respirologists in the Netherlands, France, and Italy individualized the night prescription more frequently. Although oxygen during exercise was individualized in most countries (74%), significant differences remained among countries (p<0.001). The majority of respirologists (62%) aimed to achieve an Sa,O2 of 90-91% during exercise, while 70% of all respirologists tried to achieve the desired Sa,O2 for 90% of the test. There were substantial differences among countries as to how the oxygen prescription was written. This survey highlights the need for multicentre studies that improve the effectiveness of long-term oxygen therapy utilization.

Omapatrilat: neurohormonal and pharmacodynamic profile when administered with furosemide

Pharmacodynamic effects of combination therapy with omapatrilat and furosemide were evaluated. Two groups of 13 healthy subjects each received furosemide 20 mg dailyfor 15 days coadministered with either placebo on days 6 to 15 or omapatrilat 10 mg on days 6 to 10 and 25 mg on days 11 to 15. In the omapatrilat group, urinary excretion of atrial natriuretic peptide increased, and greater blood pressure reductions were seen compared with placebo. Concomitant omapatrilat treatment did not affect the acute diuresis, natriuresis, and kaliuresis observed with chronic administration of furosemide. Neither effective renal plasma flow nor glomerularfiltration rate changed in either treatment group. No clinically significant safety issues were observed. Daily coadministration of omapatrilat 10 or 25 mg with furosemide 20 mg does not affect the pharmacodynamics offurosemide at steady state.

Effect of food on the oral bioavailability of UFT and leucovorin in cancer patients

UFT is composed of tegafur (FT), a prodrug of 5-fluorouracil (5-FU), and uracil in a fixed combination (1:4). In conjunction with leucovorin, UFT is being developed for the first-line oral treatment of metastatic colorectal cancer. The effect of food on the oral bioavailability of UFT (2 x 100 mg capsules; dose in terms of FT) and leucovorin (2 x 15 mg tablets) was evaluated in a single-dose, randomized, two-way crossover study. Patients (n = 25) were assigned to receive both drugs after an overnight fast or 5 min after completion of a high-fat meal (721 calories) with a 3-day washout period between treatments; then they were permitted to continue on oral UFT/leucovorin therapy for safety assessment. UFT (300 mg/m2/day as three divided doses) and leucovorin (90 mg/day as three divided doses) were given for 28 days. After a 7-day rest, the 28-day cycle was repeated. Pharmacokinetics (n = 22 patients) were determined for FT, 5-FU, uracil, leucovorin, and 5-methyltetrahydrofolate (an active metabolite of leucovorin). The absence of food-effect on peak plasma concentration (CMAX) and the area under the curve (AUC) was concluded if the 90% confidence interval for the ratio of the treatment means was entirely contained in 0.75-1.33. Administration of UFT with food resulted in a 34% decrease in CMAX of FT, whereas the AUC of FT remained unchanged. Food decreased the CMAX and AUC values of uracil and 5-FU by 37-76%. On the contrary, the CMAX and AUC values of leucovorin and 5-methyltetrahydrofolate were increased by 14-60% with food. Time to reach CMAX for all analytes was significantly (P < or = 0.001) delayed by food. Except for the AUCs of FT, the statistical criterion for concluding a lack of food-effect was not met. These data suggest that UFT/leucovorin should not be dosed simultaneously with food. It is recommended that food should not be consumed for 1 h before and after an oral dose of UFT and leucovorin in a manner similar to pivotal Phase III trials. The 28-day oral regimen of UFT and leucovorin was generally well tolerated in the population studied.

Nutritional intervention in COPD: a systematic overview

OBJECTIVE

We conducted a systematic overview of randomized controlled trials (RCTs) to clarify the contribution of nutritional supplementation for patients with stable COPD.

METHODS

RCTs were identified from several sources, including the Cochrane Airways Group register of RCTs, a hand search of abstracts presented at international meetings, and consultation with experts. Two reviewers independently selected trials for inclusion, assessed quality, and extracted the data.

RESULTS

Twenty-one reports were classified according to the type, duration of supplementation, and the presence of anabolic substances. High carbohydrate meals were associated with an increase in carbon dioxide production and a decrease in exercise capacity. Short-term crossover studies in which diets of various compositions were administered supported the notion that high carbohydrate loads increase the stress on the ventilatory system. The influence of longer-term supplementation (> 2 weeks) on weight, anthropometry, and exercise capacity varied, without there being a consistent effect. Lean body weight was only occasionally reported and health-related quality of life too rarely to be included as an outcome. The influence of recombinant human growth hormone was disappointing. Anabolic steroids increased body weight and lean body mass, but had little influence on exercise capacity.

CONCLUSION

This systematic overview in patients with COPD supports the notion that those with marginal ventilatory reserve might benefit from a dietary regimen in which a high percentage of calories are supplied by fat. Although there are reports of the benefits of nutritional repletion, trials of > 2 weeks failed to show consistent benefit on body weight. Evaluating nutritional repletion is hampered by the absence of information regarding body composition, exercise, and health-related quality of life. Growth hormone has not been shown to be useful. Further studies are needed to refine the beneficial effects of anabolic steroids as adjunctive agents together with nutritional support and exercise.

Critical appraisal of clinical practice guidelines targeting chronic obstructive pulmonary disease

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is so prevalent that the endorsement of management strategies by professional organizations issuing clinical practice guidelines (CPGs) will likely influence the clinical and financial resources allocated to this condition.

OBJECTIVES

To examine the content of and to critically appraise the CPGs targeting COPD.

METHODS

We identified, through a MEDLINE search (from January 1990 to May 1999) and contacts with experts and professional organizations, the CPGs for the overall management of COPD. We assessed the guidelines according to an index of quality measuring 3 dimensions: the rigor of development, the context and content, and the extent to which the dissemination and implementation have been addressed. The recommendations were also examined and compared.

RESULTS

Of the 15 CPGs we included, none was based on a systematic review of the literature. Two were independently reviewed before their release, 1 included strategies for dissemination and implementation, and 1 estimated the economic implications associated with its recommendations. The recommendations were often difficult to interpret (reviewers' agreement: kappa median, 0.41). When unanimity existed regarding the benefits of a given management modality (such as respiratory rehabilitation), discrepancies were often identified in the application of the recommendation.

CONCLUSIONS

The methodological quality of CPGs targeting COPD is limited, and there are disparities among many of their recommendations. Despite there being several CPGs worldwide, there is a need for an evidence-based summary of the literature to serve as a resource for those who provide health care to individuals with COPD.

Corrosion-fatigue life of commercially pure titanium and Ti-6Al-4V alloys in different storage environments

STATEMENT OF PROBLEM

Removable partial dentures are affected by fatigue because of the cyclic mechanism of the masticatory system and frequent insertion and removal. Titanium and its alloys have been used in the manufacture of denture frameworks; however, preventive agents with fluorides are thought to attack titanium alloy surfaces.

PURPOSE

This study evaluated, compared, and analyzed the corrosion-fatigue life of commercially pure titanium and Ti-6Al-4V alloy in different storage environments.

MATERIAL AND METHODS

For each metal, 33 dumbbell rods, 2.3 mm in diameter at the central segment, were cast in the Rematitan system. Corrosion-fatigue strength test was carried out through a universal testing machine with a load 30% lower than the 0.2% offset yield strength and a combined influence of different environments: in air at room temperature, with synthetic saliva, and with fluoride synthetic saliva. After failure, the number of cycles were recorded, and fracture surfaces were examined with an SEM.

RESULTS

ANOVA and Tukey's multiple comparison test indicated that Ti-6Al-4V alloy achieved 21,269 cycles (SD = 8,355) against 19,157 cycles (SD = 3, 624) for the commercially pure Ti. There were no significant differences between either metal in the corrosion-fatigue life for dry specimens, but when the solutions were present, the fatigue life was significantly reduced, probably because of the production of corrosion pits caused by superficial reactions.

A comparative description of three multipurpose phantoms (MPP) for external audits of photon beams in radiotherapy: the water MPP, the Umeå MPP and the EC MPP

AIM

To present a technical description and intercomparison of three multipurpose phantoms (MPP) developed for mailed dosimetry checks of therapeutic photon beams in reference and non-reference conditions.

MATERIALS

The W-MPP is a water MPP, whereas the Umeâ-MPP, made of perspex (PMMA, Plexiglas), and the EC-MPP, made of polystyrene, are solid MPPs. The W-MPP uses only thermoluminescent dosimeters (TLD) for dosimetry checks, the EC MPP uses film and TLD; the Umeâ phantom uses film and TLD, and offers in addition the possibility for ionization chamber measurements. Either using TLD or films, the MPPs have been designed to check on-axis and off-axis the following irradiation conditions: square and rectangular fields, asymmetric fields, wedged beams, oblique incidence and, for the solid MPPs, also the influence of inhomogeneities.

RESULTS AND DISCUSSION

The MPPs have been compared for different aspects going from their dosimetric performance (number of dosimetric parameters that can be checked) to some practical consideration in the use of the different MPPs (set-up time, stability, instruction sheets, etc.). From a comparison between the solid multi-purpose phantoms, it turns out that the EC-MPP is capable of checking the largest number of dosimetric parameters per beam, but has the longest set-up time ( approximately 2 h) per beam according to the users. The Umeå-MPP has a smaller number of set-ups (hence a smaller average time) and also includes some parameters not checked with the EC-MPP (e.g. SSD accuracy). The major drawback however of the Umeå-MPP is considered to be its high density (>1.1 g/cm(3)) which increases the difficulty of the analysis with the treatment planning system. The W-MPP checks the smallest number of parameters, but is the fastest in set-up time, the easiest for mailing, and is water equivalent, which is advantageous for the TPS checks. The major drawback of this MPP is however the inability to check complete dose distribution (film) or inhomogeneities.

Defibrotide as salvage therapy for refractory veno-occlusive disease of the liver complicating allogeneic bone marrow transplantation

A 30-year-old woman developed veno-occlusive disease of the liver during an allogeneic BMT for acute leukemia. Treatment with recombinant human tissue plasminogen activator and heparin resulted in an incomplete and transient response followed by progressive disease. The patient was then given defibrotide (DF), a mammalian tissue-derived polydeoxyribonucleotide developed for the treatment of a number of vascular disorders, which has thrombolytic and anti-thrombotic properties. No significant bleeding or other major toxicities were observed during treatment and she made a full recovery. At 6 months after the onset of VOD her liver function tests and color flow Doppler ultrasound scan are normal. Our experience supports the preliminary results already obtained with DF. Its efficacy should be evaluated in a prospective randomized fashion.

Bioavailability and phase II study of oral UFT plus leucovorin in patients with relapsed or refractory colorectal cancer

PURPOSE

This study was undertaken to address the influence of concurrent administration on the pharmacokinetics of UFT (uracil plus tegafur) and leucovorin (LV), and to measure the antitumor activity of a 28-consecutive-day oral regimen of UFT plus LV in patients with relapsed or refractory colorectal cancer.

METHODS

Patients with advanced measurable colorectal cancer who had failed previous therapy with intravenous bolus 5-fluorouracil (5-FU) were eligible. Patients were treated with UFT 300 mg/m2 per day plus LV 90 mg per day in three divided doses every 8 h for 28 days, repeated at 35-day intervals. In addition, a three-treatment by three-period crossover bioavailability comparison of oral LV 30 mg plus UFT 200 mg versus either LV or UFT alone was scheduled for the 8 days preceding the first cycle of therapy.

RESULTS

Of 19 patients enrolled, 18 were assessable for pharmacokinetics and response. When LV was coadministered with UFT, there were no statistically significant effects on tegafur, uracil, or 5-FU Cmax, AUC, or Tmax with the exception of a delayed Tmax for tegafur (P=0.03). No statistically significant differences were found in LV and 5-methyltetrahydrofolate plasma levels when LV was administered alone or with UFT. However, wide interpatient variability was observed for all parameters. There were no antitumor responses seen.

CONCLUSIONS

Although the Tmax for tegafur is delayed with the concurrent administration of LV, there were no differences (P > 0.05) in any pharmacologic parameters that are of likely clinical significance. However, the great interpatient variability observed in UFT and LV pharmacology may have obscured true bioavailability effects in this small patient population. Daily oral UFT plus LV is inactive as second-line therapy in patients who have failed bolus 5-FU.