Toward the development of sensors for lung cancer: The adsorption of 1-propanol on hydrophobic zeolites

A healthy breath is mainly composed of water, carbon dioxide, molecular nitrogen, and oxygen and it contains many species, in small quantities, which are related to the ambient atmosphere and the metabolism. The breath of a person affected by lung cancer presents a concentration of 1-propanol higher than usual. In this context, the development of specific sensors to detect 1-propanol from breath is of high interest. The amount of propanol usually detected on the breath is of few ppb; this small quantity is a handicap for a reliable diagnostic. This limitation can be overcome if the sensor is equipped with a pre-concentrator. Our studies aim to provide an efficient material playing this role. This will contribute to the development of reliable and easy to use lung cancer detectors. For this, we investigate the properties of a few hydrophobic porous materials (chabazite, silicalite-1, and dealuminated faujasite). Hydrophobic structures are used to avoid saturation of materials by the water present in the exhaled breath. Our experimental and simulation results suggest that silicalite -1 (MFI) is the most suitable structure to be used as a pre-concentrator.

Influence of kinematic alignment on femorotibial kinematics in medial stabilized TKA design compared to mechanical alignment

INTRODUCTION

Worldwide more and more primary knee replacements are being performed. Kinematic alignment (KA) as one of many methods of surgical alignment has been shown to have a significant impact on kinematics and function. The aim of the present study was to compare KA and mechanical alignment (MA) with regard to femorotibial kinematics.

MATERIALS AND METHODS

Eight fresh frozen human specimens were tested on a knee rig during active knee flexion from 30 to 130°. Within the same specimen a medial stabilized (MS) implant design was used first with KA and then with MA.

RESULTS

The femorotibial kinematics showed more internal rotation of the tibia in KA compared to MA. At the same time, there was a larger medial rotation point in KA. Both alignment methods showed femoral rollback over the knee bend.

CONCLUSION

Relating to an increased internal rotation and a more precise medial pivot point, it can be concluded that KA combined with a MS implant design may partially support the reproduction of physiological knee joint mechanics.

When less is more: does more Na+-cations mean more adsorption sites for toluene in faujasites?

The unique properties of zeolites make them an interesting material to be used in separation processes. The possibility of tailoring some of their characteristics, like the Si/Al ratio, allows optimizing their synthesis for a given task. Concerning the adsorption of toluene by faujasites an understanding of the effect of cations is necessary to foster the elaboration of new materials, which can capture molecules with a high degree of selectivity and sensitivity. Undoubtedly, this knowledge is relevant for a wide range of applications going from the elaboration of technologies for improving the air-quality to diagnostic procedures to prevent health risks. The studies reported here using Grand Canonical Monte Carlo simulations elucidate the role of Na-cations in the adsorption of toluene by faujasites with different Si/Al ratios. They detail how the location of the cations inhibits or enhances the adsorption. The cations located at site II are shown to be those enhancing the adsorption of toluene on faujasites. Interestingly, the cations located at site III generate a hindrance at high loading. This becomes an impediment for the organization of toluene molecules inside faujasites.

Kirkwood-Buff integrals: From fluctuations in finite volumes to the thermodynamic limit

The Kirkwood-Buff theory is a cornerstone of the statistical mechanics of liquids and solutions. It relates volume integrals over the radial distribution function, so-called Kirkwood-Buff integrals (KBIs), to particle number fluctuations and thereby to various macroscopic thermodynamic quantities such as the isothermal compressibility and partial molar volumes. Recently, the field has seen a strong revival with breakthroughs in the numerical computation of KBIs and applications to complex systems such as bio-molecules. One of the main emergent results is the possibility to use the finite volume KBIs as a tool to access finite volume thermodynamic quantities. The purpose of this Perspective is to shed new light on the latest developments and discuss future avenues.

Hypofractionated postoperative stereotactic radiotherapy for large resected brain metastases

PURPOSE

The aim of the present retrospective study was to report outcomes after hypofractionated stereotactic radiotherapy (HSRT) for resected brain metastases (BM).

PATIENTS AND METHODS

We reviewed results of patients with resected BM treated with postoperative HSRT (3×7.7Gy to the prescription isodose 70%) between May 2013 and June 2020. Local control (LC), distant brain control (DBC), overall survival (OS), leptomeningeal disease relapse (LMDR), and radiation necrosis (RN) occurrence were reported.

RESULTS

Twenty-two patients with 23 brain cavities were included. Karnofsky Performance status (KPS) was≥70 in 77.3%. Median preoperative diameter was 37mm [21.0-75.0] and median planning target volume (PTV) was 23 cm³ [9.9-61.6]. Median time from surgery to SRT was 69 days [7-101] and 48% of patients had a local relapse on pre-SRT imaging. Median follow-up was 17.5 months [1.6-95.9]. One and two-year LC rates were 60.9 and 52.2% respectively. One and 2-year DBC rates were 45.5 and 40.9%. Median OS was 16.5 months. Four patients (18.2%) presented LMDR during follow-up. RN occurred in 6 patients (27.2%). Three factors were associated with OS: ECOG-PS (P=0.009), KPS (P=0.04), and cystic metastasis before surgery (P=0.037). Several factors were related to RN occurrence: PTV diameter and volume, Normal brain V21, V21 and V24 isodoses volumes.

CONCLUSION

HSRT is the most widely used scheme for larger brain cavities after surgery. The optimal dose and scheme remain to be defined as well as the optimal delay between postoperative SRT and surgery. Dose escalation may be necessary, especially in case of subtotal resection.

[Efficacy and tolerance of salvage curative radiotherapy for patients with cervical relapse of differentiated thyroid carcinoma]

PURPOSE

Radiation therapy is often the last resource treatment for cervical relapse in iodine refractory differentiated thyroid cancer. We present locoregional control data in patients with cervical relapse treated with curative intent radiation therapy with or without concomitant carboplatin.

MATERIAL AND METHODS

This monocentric retrospective study gathered data on patients with differentiated thyroid carcinoma - vesicular or papillary - in relapse after thyroidectomy who received a curative intent cervical radiation therapy. Locoregional progression free survival (LRPFS), progression free survival (PFS), overall survival (OS) were gathered as well as acute and chronic adverse events assessed with the CTCAE v4.

RESULTS

Thirty-nine patients were consecutively included between 2005 and 2019. The median follow-up was 36.6months. Fifteen patients (38%) had a locoregional relapse, locoregional control at 2years was 66.7%. The median LRPFS was 48months [32.9-not reached] and the median overall survival 49months [38.8-not reached]. In multivariate analysis, initial incomplete resection was associated with poorer OS (HR: 24.39 [3.57-166.78], P=0.00113) and LRPFS (HR: 33.91 [4.46-257.61], P=0.00066), extra nodal spread was associated with poorer LRPFS (HR: 13.45 [1.81-99,76], P=0.011). ECOG performance status was associated with OS (HR: 5.11 [1.57-16.66], P=0.00688). Carboplatin association with radiation therapy was not associated with improved survivals (OS: P=0.34, LRPFS: P=0.84). The rate of acute grade 3 toxicities was 14%.

CONCLUSION

Salvage cervical radiation therapy was associated with a locoregional control of 66.7% at 2years with a reasonable toxicity rate. Carboplatin association with radiation therapy did not improve locoregional control nor overall survival in comparison with radiotherapy alone.

Radiotherapy of non-tumoral refractory neurological pathologies

Intracranial radiotherapy has been improved, primarily because of the development of stereotactic approaches. While intracranial stereotactic body radiotherapy is mainly indicated for treatment of benign or malignant tumors, this procedure is also effective in the management of other neurological pathologies; it is delivered using GammaKnife® and linear accelerators. Thus, brain arteriovenous malformations in patients who are likely to experience permanent neurological sequelae can be managed by single session intracranial stereotactic body radiotherapy, or radiosurgery, in specific situations, with an advantageous benefit/risk ratio. Radiosurgery can be recommended for patients with disabling symptoms, which are poorly controlled by medication, such as trigeminal neuralgia, and tremors, whether they are essential or secondary to Parkinson's disease. This literature review aims at defining the place of intracranial stereotactic body radiotherapy in the management of patients suffering from non-tumoral refractory neurological pathologies. It is clear that the multidisciplinary collaboration of experienced teams from Neurosurgery, Neurology, Neuroradiology, Radiation Oncology and Medical Physics is needed for the procedures using high precision radiotherapy techniques, which deliver high doses to locations near functional brain areas.

[Treatment of radiation-induced late effects: What's new?]

Mechanisms of late radio-induced lesions are the result of multiple and complex phenomena, with many entangled cellular and tissue factors. The biological continuum between acute and late radio-induced effects will be described, with firstly a break in homeostasis that leads to cellular redistributions. New insights into late toxicity will finally be addressed. Individual radiosensitivity is a primary factor for the development of late toxicity, and clinicians urgently need predictive tests to offer truly personalized radiation therapy. An update will be made on the various functional and genetic tests currently being validated. The management of radio-induced side effects remains a frequent issue for radiation oncologists, and an update will be made for certain specific clinical situations. Finally, an innovative management for patients with significant side effects after pelvic radiotherapy will be developed, involved mesenchymal stem cell transplantation, with the presentation of the "PRISME" protocol currently open to patients recruitment.

P1475Impact of automatic screening and parasternal rights positions in the eligibility of patients with hypertrophic cardiomyopathy for subcutaneous automatic cardioverter defibrillator implant

Background

A high percentage of failures in the detection of QRS and T wave in patients (pts) with hypertrophic cardiomyopathy (HCM) have been reported. This finding would prevent them from being eligible for an implantable subcutaneous automatic defibrillator (S-ICD). However, recently 2 changes in the detection have been proposed, automatic screening and the use of right parasternal position of the lead. 

The aim of our work was to study if the elegibility proportion of patients  was increased with both 2 advacements.

Methods

We included 31 patients (18 male)with a diagnosis of HCM and at least 1 risk factor for sudden death, in follow-up at the outdoor clinic of of 2 cardiology centers. We performed elegibility screening test in supine position and standing using both the automatic screening (AS) obtained by Boston Scientific Zoom Latitude programmer) and the manual (MS), to simulate the detection of the 3 vectors utilized in S-ICD detection. And both screens were registered with the surface electrodes in parasternal left and right position. A pte was considered eligible if at least one vector was correct in supine position and in standing position, well in parasternal left or right position.

Results

Using MS with left parasternal position, 22 patients (71%) were eligible.  Adding the right parasternal lead, the eligibility increased by 10%,  reaching 81%. In addition, in automatic screening, eligibility in right shifts (81%) it is 7% more than in the left and, with the addition of the rights to the left, the eligibility reaches up to 84%. Figure shows the three-lead ECG factors influencing screening pass vs failure.

Conclusion

AS, right parasternal lead position and the combination of right and left parasternal lead position, increase the eligibility of sICD candidates with HCM.

Abstract Figure. ECG factors influencing screening pass

[Chemoradiation for oesophageal cancer: A critical review of the literature]

Locally advanced oesophageal cancer treatment requires a multidisciplinary approach with the combination of chemotherapy and radiotherapy for preoperative and definitive strategy. Preoperative chemoradiation improves the locoregional control and overall survival after surgery for locally advanced oesophageal cancer. Definitive chemoradiation can also be proposed for non-resectable tumours or medically inoperable patients. Besides, definitive chemoradiation is considered as an alternative option to surgery for locally advanced squamous cell carcinomas. Chemotherapy regimen associated to radiotherapy consists of a combination of platinum derived drugs (cisplatinum or oxaliplatin) and 5-fluorouracil or a weekly scheme combination of carboplatin and paclitaxel according to CROSS protocol in a neoadjuvant strategy. Radiation doses vary from 41.4Gy to 45Gy for a preoperative strategy or 50 to 50.4Gy for a definitive treatment. The high risk of lymphatic spread due to anatomical features could justify the use of an elective nodal irradiation when the estimated risk of microscopic involvement is higher than 15% to 20%. An appropriate delineation of the gross tumour volume requires an exhaustive and up-to-date evaluation of the disease. Intensity-modulated radiation therapy represents a promising approach to spare organs-at-risk. This critical review of the literature underlines the roles of radiotherapy for locally advanced oesophageal cancers and describes doses, volumes of treatment, technical aspects and dose constraints to organs-at-risk.

[Clinical research for rectal carcinoma: State of the art and objectives]

The treatment of rectal carcinoma is based on multidisciplinary strategy and multimodal approaches including gastrointestinal tract specialists, medical oncologists, radiation oncologists and surgery. The different objectives should be declined according to the characteristics of the tumours. The aim of the therapist would be to select the best strategy offering to the patient to be cured with as less as possible late adverse toxicity. The challenge of the treatment of small tumours is to maintain a functional anal sphincter while minimizing the risk of local recurrence. The standard treatment of locally advanced disease is aiming firstly to cure the patient and secondly to prevent late complications. Each of these clinical presentations of the disease has to be considered as a whole taking into account the new surgical techniques and a personalized approach adapted to the tumour. Nowadays they should be studied with dedicated clinical trials.

Association between depression and anemia in otherwise healthy adults

OBJECTIVE

It remains debated whether anemia is associated with depression, independently of physical health factors. We report a large-scale cross-sectional study examining this association in adults free of chronic disease and medication from the general population.

METHOD

Hemoglobin levels were measured among 44 173 healthy participants [63% men; mean [standard deviation] age = 38.4 (11.1) years] from the 'Investigations Préventives et Cliniques' (IPC) cohort study. Depression was measured with the Questionnaire of Depression 2nd version, Abridged. Logistic regression analyses were performed to examine the association between anemia and depression, while adjusting for a wide range of sociodemographic characteristics and health-related factors (i.e., sex, age, living status, education level, occupational status, alcohol intake, smoking status, physical activity, and body mass index).

RESULTS

Depressed participants were significantly more likely to have anemia compared to non-depressed participants, even after adjustment for sociodemographic and health-related variables [odds ratio = 1.36; 95% confidence interval = (1.18; 1.57)]. Anemia prevalence increased with depression severity, suggesting a dose-response relationship (P for trend <0.001).

CONCLUSION

In healthy adults from the general population, we found a significant and robust association between depression and anemia. Further studies are needed to assess the longitudinal relationship between both conditions and determine the mechanisms underlying this association.

Association between current perceived stress and incident diabetes is dependent on occupational status: Evidence from the IPC cohort study

AIM

The role of stress in the onset of type 2 diabetes is a widespread lay belief, yet observational studies have produced inconsistent results. This study aimed to test the hypothesis that the association between perceived stress and incident diabetes might depend on occupational status (OS).

METHODS

The four-item Perceived Stress Scale (PSS-4) was completed at baseline by 22,567 participants in the labour force (16,193 men, 6374 women; mean age: 44.5±9.8 years) who had undergone two health checkups subsidized by the French national healthcare system. All subjects were free from diabetes at baseline, defined as a fasting blood glycaemia≥7mmol/L or the use of antidiabetic drugs.

RESULTS

After a mean follow-up of 5.3±2.1 years, 527 participants (2.3%) had incident diabetes. After adjusting for sociodemographic, behavioural and biomedical risk factors as well as self-rated health, the association between baseline perceived stress and diabetes at follow-up was non-significant for the total study population. However, perceived stress was significantly associated with incident diabetes in participants of low OS [odds ratio (OR) for a five-point increment: 1.39; 95% confidence interval (CI): 1.02-1.90]. In contrast, there was a negative association between perceived stress and diabetes among those of high OS (OR: 0.60; 95% CI: 0.41-0.88) and no association within other occupational categories. The interaction between perceived stress and OS was significant (P<0.01).

CONCLUSION

This study suggests that the association between perceived stress and diabetes onset is dependent on OS. Furthermore, this association does not appear to be explained by the classical risk factors for diabetes.

Individual 6-year systolic blood pressure change and impact on cardiovascular mortality in a French general population

Impact of blood pressure (BP) visit-to-visit variability remains controversial for untreated hypertensives and for normotensive subjects. Association between 6-year systolic BP change and all-cause and cardiovascular (CVD) mortality was studied in general primary care population including untreated hypertensive and normotensive subjects. Normotensive individuals and untreated high BP patients (40,926 and 14,283, respectively) had two check-ups (interval: 5.8±2.2 years) at the IPC center (Paris). Follow-up was 6.1±3.2 years: 1131 people died, 114 from CVD causes. Systolic BP (SBP) change was assessed by tertiles of absolute differences between V1 and V2, and the relationship with mortality was analysed with multivariate Cox models (hazard ratio (HR), 95% confidence interval (CI)) including V1 or V2 parameters notably SBP. Adjusting for V1 variables, mortality was associated with SBP change, for the entire population (all-cause: HR=1.15 (95%: 1.01-1.30) and CVD: HR=1.95 (95%: 1.25-3.05)) and in hypertensive individuals: (HR=1.31 (95%: 1.08-1.59) and HR=2.51 (95%: 1.34-4.72), respectively). Adjustments for V2 variables gave similar results. For those who were normotensive at V1, the associations were not significant. In this primary care population, individual long-term visit-to-visit change of BP is an independent predictor of all-cause mortality in hypertensive individuals but not in those with normal BP.

Stereotactic radiotherapy for large solitary brain metastases

PURPOSE

To assess effectiveness and toxicity levels of stereotactic radiation therapy without whole brain radiation therapy in patients with solitary brain metastases larger than 3cm.

PATIENTS AND METHODS

Between June 2007 and March 2009, 12 patients received fractionated stereotactic radiation therapy and 24 patients underwent stereotactic radiosurgery. For the fractionated stereotactic radiation therapy group, 3×7.7Gy were delivered to the planning target volume (PTV); median volume and diameter were 29.4 cm(3) and 4.4cm, respectively. For the stereotactic radiosurgery group, 14Gy were delivered to the PTV; median volume and diameter were 15.6 cm(3) and 3.7cm, respectively.

RESULTS

Median follow-up was 218 days. For the fractionated stereotactic radiation therapy group, local control rates were 100% at 360 days and 64% at 720 days; for the stereotactic radiosurgery group, rates were 58% at 360 days and 48% at 720 days (P=0.06). Median survival time was 504 days for the fractionated stereotactic radiation therapy group and 164 days for the stereotactic radiosurgery group (P=0.049). Two cases of grade 2 toxicity were observed in the fractionated stereotactic radiation therapy group, and 6 cases of grade 1-2 toxicity, in the stereotactic radiosurgery group.

CONCLUSIONS

This study provides data to support that fractionated stereotactic radiation therapy without whole brain radiation therapy with a margin dose of 3 fractions of 7.7Gy for treatment of solitary large brain metastases is efficient and well-tolerated. Because of the significant improvement in overall survival, this schedule should be assessed in a randomized trial.

[Securitization of the bi-site radiotherapy activity as part of the resumption of treatments in the Hospital of Epinal by the team of Alexis Vautrin Nancy Cancer Center]

In February 2007, the radiation therapy department of the Jean Monnet Hospital in Epinal (France) has stopped the radiotherapy treatments after the discovery of a radiotherapy accident and bad practices leading to overexposure of patients between 1987 and 2006. The Regional Cancer Center "Centre Alexis Vautrin" in Nancy (France) was given the task of the new start of treatment activity. From February 2007 to January 2008, actions of training, updates of equipments and practices have been performed in the Epinal Hospital, guided by the quality approach, allowing the treatment of new patients in February 2008, with the radiation oncologists and the medical physicists of the Centre Alexis Vautrin, with the highest conditions of security and confidence.

[Should elderly patients with glioblastoma be proposed to radiotherapy?]

In glioblastoma multiform-patients, advanced age has been associated with poor prognosis and decreased tolerance to treatments. The optimal management, especially with irradiation, was not definitively determined in the eighth and ninth decades. The Association of French-speaking neuro-oncologists (Anocef) has recently conducted a randomized clinical trial comparing radiotherapy plus supportive care versus supportive care alone in such patients. Patients aged 70-years and older with newly diagnosed glioblastoma and a Karnofsky performance score of 70 or above were randomly assigned to receive focal irradiation in daily fraction of 1.8 Gy given five days per week for a total dose of 50 Gy plus supportive care or supportive care only. Radiotherapy resulted in a modest but significant improvement in overall survival without reducing quality of life or cognition. However, the optimal regimen of radiotherapy in this fragile population remains uncertain. Abbreviated course of radiotherapy (40 Gy in 15 fractions over 19 days) has been proposed. Analysis of preliminary results showed that efficacy and safety of this hypofractionated accelerated regimen compared favourably with those of classically fractionated treatments. Finally, the potential contribution of surgery and chemotherapy should be evaluated in prospective clinical trials.

[Epinal radiotherapy accident: passed, present, future]

The accident of radiation oncology at the Public General Hospital in Epinal, Vosges, is the highest in France. It is classified level 6 on a 10 degrees scale of the ASN/SFRO (Autorité de sûreté nucléaire/Société française de radiothérapie oncologique). It is linked to errors in the process of treatment, and a mistake in the use of dynamic wedges, with an overdosage of 20%. The clinical consequences are severe, for the patients treated for a prostate cancer and exposed to this overdosage, between May 2005 and August 2006. Sequelae were classified grade 2 to 5 on the CTCAE 3.0 scale. A second cohort of 397 was identified, which received an overdose of 10% linked to the daily use of portal imaging, which explained a higher risk of gr 2-3 rectitis. The treatments were interrupted in this hospital for several months, to organize a new management of the department, based on quality and safety. The preventive actions to avoid such an accident necessitate to evaluate standard and innovative treatments, to develop an internal and external quality control program.

Thermal effects during adsorption of n-butane on a silicalite-1 membrane: A non-equilibrium molecular dynamics study

Non-equilibrium molecular dynamic (NEMD) simulations have been used to study the kinetics of adsorption of n-butane molecules in a silicalite membrane. We have chosen this simple well-known process to demonstrate that the process is characterized by two stages, both non-isothermal. In the first stage the large chemical driving force leads to a rapid uptake of n-butane in all the membrane and a simultaneous increase in the membrane temperature, explained by the large enthalpy of adsorption, DeltaH=-61.6kJ/mol butane. A diffusion coefficient for transport across the external surface layer is calculated from the relaxation time; a value of 3.4x10(-9)m(2)/s is found. During the adsorption, a significant thermal driving force develops across the external surface of the membrane, which leads to an energy flux out of the membrane during the second stage. In this stage a thermal conductivity of 3.4x10(-4)W/Km is calculated from the corresponding relaxation time for the surface, confirming that the thermal conduction is the rate-limiting step. The aim of this paper is to demonstrate that a thermal driving force must be taken into account in addition to a chemical driving force in the description of transport in nano-porous materials.

Temozolomide for low-grade gliomas: predictive impact of 1p/19q loss on response and outcome

OBJECTIVE

To evaluate the predictive impact of chromosome 1p/19q deletions on the response and outcome of progressive low-grade gliomas (LGG) treated with up-front temozolomide (TMZ) chemotherapy.

METHODS

Adult patients with measurable, progressive LGG (WHO grade II) treated with TMZ delivered at the conventional schedule (200 mg/m(2)/day for 5 consecutive days, repeated every 28 days) were retrospectively evaluated for response by central review of MRI-s. Chromosome 1p and 19q deletions were detected by the loss of the heterozygosity technique (LOH).

RESULTS

A total of 149 consecutive patients were included in this retrospective, single center observational study. The median number of TMZ cycles delivered was 14 (range 2 to 30). Seventy-seven patients (53%) experienced an objective response (including 22 [15%] cases of partial response and 55 [38%] cases of minor response), 55 (37%) patients had stable disease, and 14 (10%) had a progressive disease. The median time to maximum tumor response was 12 months (range 3 to 30 months). The median progression-free survival (PFS) was 28 months (95% CI: 23.4 to 32.6). Material for genotyping was available for 86 patients. Combined 1p/19q LOH was present in 42% of the cases and was significantly associated with a higher rate (p = 0.02) and longer objective response to chemotherapy (p = 0.017), and both longer PFS (p = 4.10(-5)) and overall survival (p = 0.04).

CONCLUSION

Low-grade gliomas respond to temozolomide and loss of chromosome 1p/19q predicts both a durable chemosensitivity and a favorable outcome.

Transfer coefficients for evaporation of a system with a Lennard-Jones long-range spline potential

Surface transfer coefficients are determined by nonequilibrium molecular dynamics simulations for a Lennard-Jones fluid with a long-range spline potential. In earlier work [A. Røsjorde, J. Colloid Interface Sci. 240, 355 (2001); J. Xu, ibid. 299, 452 (2006)], using a short-range Lennard-Jones spline potential, it was found that the resistivity coefficients to heat and mass transfer agreed rather well with the values predicted by kinetic theory. For the long-range Lennard-Jones spline potential considered in this paper we find significant discrepancies from the values predicted by kinetic theory. In particular the coupling coefficient, and as a consequence the heat of transfer on the vapor side of the surface are much larger. Thermodynamic data for the liquid-vapor equilibrium confirmed the law of corresponding states for the surface, when it is described as an autonomous system. The importance of these findings for modelling phase transitions is discussed.

Chimiothérapie néoadjuvante suivie d'une radiothérapie adaptée à la réponse tumorale dans les tumeurs germinales séminomateuses du système nerveux central: expérience de l'hôpital de la Pitié-Salpêtrière et revue de la littérature

PURPOSE

Retrospective analysis of ten cases of germinoma of the central nervous system treated in Pitié-Salpêtrière Hospital, Paris.

PATIENTS AND METHODS

Ten male patients were treated from 1997 to 2005 for histologically verified primary seminoma of the central nervous system. The median age was 27 years (range 18-40 years). Our option for the treatment was the association of 3-4 cycles of neoadjuvant chemotherapy (cisplatin and etoposide) to radiotherapy. Five patients received a craniospinal radiotherapy of 30 Gy (for one patient 36 Gy) followed by a tumoral boost from 20 to 24 Gy. For five patients, irradiated volume was limited to the tumour, total dose from 24 to 54 Gy (for three patients the total dose was from 24 to 30 Gy). Surgery was used for five patients, but only in one case was macroscopic complete.

RESULTS

Six patients were in situation of complete remission after neoadjuvant chemotherapy. All the patients were in situation of complete remission after the irradiation. All the patients were alive free of disease with a median follow-up 46 months (range 13-90 months).

CONCLUSION

In spite of the fact that the intracranial germinal tumours are not the subject of a consensual treatment strategy, this retrospective analysis pleads in favour of chemotherapy followed by limited dose and volume irradiation.

Interface Film Resistivities for Heat and Mass TransfersIntegral Relations Verified by Non-equilibrium Molecular Dynamics

Integral relations that predict interface film transfer coefficients for evaporation and condensation have recently been derived. According to these relations, all coefficients can be calculated for one-component systems, using the thermal resistivity and the enthalpy profile through the interface. The integral relations were tested in this work using nonequilibrium molecular dynamics simulations for argon-like particles and n-octane molecules. The simulations confirm the integral relations within the accuracy of the calculation for both systems. Evidence is presented for the existence of an excess thermal resistivity on the gas side of the surface, and the fact that this property is decisive for interface heat and mass transfer coefficients. The integral relations were used to predict the mass transfer coefficient for n- octane as a function of surface tension. The findings are important for modeling of one-component phase transitions.

Radiothérapie des glioblastomes : de la radiobiologie à la chimiothérapie concomitante

The prognosis of glioblastoma remains extremely poor. Clinical research has been very active for thirty years, and has explored all the concepts developed in the laboratories of radiobiology. Radiosensitisation of hypoxic tumours, hyperfractioned radiotherapy, external beam radiotherapy plus stereotactic radiosurgery or brachytherapy boost, and intensity modulated radiation therapy failed to improve the results of the treatment of these patients. Concomitant chemoradiotherapy has just obtained a new success in the treatment of glioblastoma. The addition of temozolomide to radiotherapy resulted in a statistically significant survival benefit with minimal acute additional toxicity. The challenge remains to improve clinical outcomes further, and some new research pathways are open.

Temozolomide as initial treatment for adults with low-grade oligodendrogliomas or oligoastrocytomas and correlation with chromosome 1p deletions

PURPOSE

To determine the response rate of low-grade oligodendroglial tumors (LGOT) to temozolomide (TMZ) as initial treatment and to evaluate the predictive value of chromosome 1p deletion on the radiologic response.

PATIENTS AND METHODS

Adult patients with pathologically proven LGOT with progressive disease on magnetic resonance imaging (MRI) were eligible for the study. TMZ was administered at the starting dose of 200 mg/m2/d for 5 days, repeated every 28 days. Response was evaluated clinically and by central review of MRIs. Chromosome 1p and 19q deletions were detected by the loss of heterozygosity technique.

RESULTS

Sixty consecutive patients were included in the study. At the time of analysis, the median number of TMZ cycles delivered was 11. Clinically, 51% of patients improved, particularly those with uncontrolled epilepsy. The objective radiologic response rate was 31% (17% partial response and 14% minor response), whereas 61% of patients had stable disease and 8% experienced disease progression. The median time to maximum tumor response was 12 months (range, 5 to 20 months). Myelosuppression was the most frequent side effect, with grade 3 to 4 toxicity in 8% of patients. Loss of chromosome 1p was associated with objective tumor response (P < .004).

CONCLUSION

TMZ is well tolerated and provides a substantial rate of response in LGOT. Chromosome 1p loss is correlated with radiographic response and could be a helpful marker for guiding therapeutic decision making in LGOT.

Résultats de l’irradiation en conditions stéréotaxiques de rattrapage de 14 patients atteints d’un gliome de grade III ou IV

AIMS

To determine local control and overall survival rates of 14 patients treated for a grade III or IV glioma relapsing in a previously irradiated area and re-irradiated by stereotactic radiosurgery.

PATIENTS AND METHODS

From January 1997 to October 2001, 14 patients (median age 52 Years, age range 49-58 Years, Karnofski performance score 80 to 100) received radiosurgery for a relapse of grade III (3 patients) and or grade IV (10 patients) malignant gliomas. Before relapse, all patients had undergone surgery and had been given with a classical radiation protocol. Median maximum diameter and Volume of the tumors were 38.5mm (24-86mm) and 7cm3 (2-35cm3), respectively.

RESULTS

Median maximal dose at the isocenter and median minimal dose at the periphery of the lesion were 21Gy (16-38Gy) and 13Gy (9-17Gy), respectively. Mean follow-up was 8.5 Months (1-29). Median overall survival was 11.6 Months; 6-Month, 1- and 2-Year overall survival rates were 85p.100, 36p.100 and 12p.100, respectively. At univariate analysis, only histological grade was a significant prognostic factor of overall survival (p=0.03). Median disease-free survival was 8.2 Months while 6-Month and 1-Year disease-free survival rates were 69p.100 and 14p.100, respectively. According to univariate analysis, histological grade (p=0.033) and minimal dose delivered at the margin of the target Volume (p=0.02) were prognostic factors for disease-free survival. Two patients developed a symptomatic radionecrosis.

CONCLUSION

Radiosurgery of relapsed primitive high-grade brain tumors is efficient and overall survival rates were encouraging.

Immunoprophylaxis with Simulect (basiliximab) in pediatric kidney transplant recipients: results from routine clinical practice at 5 kidney transplant units

BACKGROUND

Simulect (basiliximab) was introduced in Spain in February 1999, being the first anti-interleukin-2 receptor monoclonal antibody used in our country for the prevention of acute rejection in kidney transplantation. The objective of this study was to assess the efficacy and safety of Simulect (basiliximab) in routine clinical practice in pediatric Spanish kidney transplantation units.

METHODS

In this prospective, observational study, we collected data related to demographics, parameters of efficacy, immunosuppressive therapy, and safety on kidney transplant patients treated with Simulect (basiliximab) using an on-line collection system.

RESULTS

Fifty pediatric patients at 5 kidney transplant units with 12 months follow-up included recipient mean age of 10.00 years (DS 5.40). Twenty-nine (58.00%) were boys and 21 (42.00%) were girls. Cold ischemia time was 15 hours and 50 minutes (DS 9.70 h). No patient presented with a PRA >50%. For prophylactic immunosuppression, 85.70% of patients received triple therapy with CNI (cyclosporine 48.97% or tacrolimus 36.73%), MMF (87.76%) or AZA (12.24%), and steroids. Acute rejection incidence at 12 months was 22%, including 3 steroid-resistant episodes (6%). One patient lost the graft (2%), 7 adverse events (AE) were reported (1 mild, 4 moderate, and 1 severe AE), of which none were attributed to the study drug.

CONCLUSIONS

Simulect (basiliximab) treatment of pediatric patients who underwent kidney transplantations performed in routine clinical practice showed good prophylaxis against acute rejection with excellent safety.

Influence of tamoxifen on carotid intima-media thickness in postmenopausal women

BACKGROUND

Intima-media thickness of the common carotid artery (IMT-CCA) is an early marker of atherosclerosis. Tamoxifen is a selective estrogen-receptor modulator with estrogen-like effects on cardiovascular risk factors but as-yet unexplored effects on carotid artery structure. The goal of this study was to determine the influence of tamoxifen on IMT-CCA in menopausal women.

METHODS AND RESULTS

With a predefined calculation of the sample size, 67 menopausal women with cancer who were treated with tamoxifen for > or =1 year and 37 menopausal women with cancer who were never treated with tamoxifen were enrolled. IMT-CCA, internal diameter, and pulse pressure were determined with a high-definition echotracking device and applanation tonometry in a central core laboratory that was blinded to treatment. Both groups were similar for clinical characteristics, including cardiovascular risk factors. IMT and internal diameter were significantly lower in the tamoxifen group (mean duration of treatment, 2.4+/-0.9 years) than in the control group (609+/-117 microm versus 662+/-147 microm, P=0.04, and 4.89+/-0.60 mm versus 5.12+/-0.58 mm, P=0.03, respectively). Pulse pressure was not influenced by the use of tamoxifen. After adjustment for age, cardiovascular risk factors, carotid pulse pressure, duration of menopause, and previous use of hormone replacement therapy, IMT remained significantly lower among tamoxifen users (P<0.00001), with an impact on IMT (-70 microm) equivalent to spontaneous evolution with 12 years of aging (5 microm/y).

CONCLUSION

The use of tamoxifen was associated with a significantly lower carotid IMT in menopausal women with cancer. Randomized trials are needed to confirm the cardioprotective effect of selective estrogen-receptor modulators in terms of prevention of atherosclerosis.

[Comparison with dose-volume histograms of two conformal irradiation techniques used for the treatment of T2N0M0 nasopharyngeal cancer, one with association of photons and protons and another with photons alone]

Purpose- There is a relationship between the local control rate of the nasopharyngeal cancer and the total dose delivered within the tumoral volume. In contrast, the relation between the dose and the irradiated volume and the risk of complication is not clearly defined. That is why, in patients presenting with a locally advanced nasopharyngeal cancer, we compared the dose-volume distribution of irradiated tissues, obtained from two 3D conformal irradiation techniques. Patients and methods- Between January 2000 and June 2001, 5 patients, 3 males and 2 females, with a median age of 32 years and presenting with a T4N0M0 nasopharyngeal cancer received a chemoradiotherapy. Radiotherapy combined photons and protons beams and the platin-based chemotherapy was delivered in three intravenous injections at d1, 22, 43 of the irradiation. To calculate the dosimetry, a CT scan and a MRI were performed in all the patients. The gross tumor volume (GTV) was delineated from the imagery, three clinical tumor volumes were defined, the CTV1 was the GTV and the whole nasopharynx, the CTV2 was the CTV plus a 10 mm-margin and the CTV3 was the CTV2 and the nodes areas (cervical and subclavicular). Prophylactic dose within node areas was 44 Gy. Prescribed doses within CTV2 and GTV or CTV1 were 54 Gy/CGE (Cobalt Gy Equivalent, for an EBR = 1,1) and 70 Gy/CGE, respectively. Irradiation was delivered with fractions of 1.8 or 2.0 Gy/CGE, with 44 Gy or 54 Gy by photons and with 16 or 26 CGE by protons. According to dose-volume histograms obtained from the dosimetry planning by protons and photons and from the theoretical dosimetry by photons lonely, for the different volumes of interest, GTV, CTV2, and organs at risk (optic nerves, chiasm, internal ears, brainstem, temporal lobes), we compared the averages of the maximum, minimum and mean doses and the averages of the volumes of organs of interest encompassed by different isodoses.Results- Calculated averages of minimum, maximum and mean doses delivered within GTV were superior for the treatment with combined photons and protons than with photons alone. The average GTV encompassed by the 70 Gy/CGE isodose was larger by 65% with the association compared to photons alone. The conformation ratio (tissue volume encompassed by the 95% isodose/GTV encompassed by the 95% isodose) was 3.1 with the association compared to 5.7 with photons alone. For the CTV2, there were no differences in different criteria according to the both irradiation techniques. For the critical, radiosensitive organs, the comparison of the majority of the criteria was in favour of the association of protons and photons. Overall, 78% of the criteria were in favour of the association.Conclusion- For locally advanced nasopharyngeal cancer without clinical adenopathy, irradiation by photons and protons increases the tumor volume irradiated at the prescribed dose and decreases the volume or critical organs irradiated and the total dose delivered within them.

[Target-volume and critical-organ delineation for conformal radiotherapy of prostate cancer: experience of French dose-escalation trials]

The delineation of target volume and organs at risk depends on the organs definition, and on the modalities for the CT-scan acquisition. Inter-observer variability in the delineation may be large, especially when patient's anatomy is unusual. During the two french multicentric studies of conformal radiotherapy for localized prostate cancer, it was made an effort to harmonize the delineation of the target volumes and organs at risk. Two cases were proposed for delineation during two workshops. In the first case, the mean prostate volume was 46.5 mL (extreme: 31.7-61.3), the mean prostate and seminal vesicles volume was 74.7 mL (extreme: 59.6-80.3), the rectal and bladder walls varied respectively in proportion from 1 to 1.45 and from 1 to 1.16; in the second case, the mean prostate volume was 53.1 mL (extreme: 40.8-73.1), the volume of prostate plus seminal vesicles was 65.1 mL (extreme: 53.2-89), the rectal wall varied proportionally from 1 to 1, 24 and the vesical wall varied from 1 to 1.67. For participating centers to the french studies of dose escalation, a quality control of contours was performed to decrease the inter-observer variability. The ways to reduce the discrepancies of volumes delineation, between different observers, are discussed. A better quality of the CT images, use of urethral opacification, and consensual definition of clinical target volumes and organs at risk may contribute to that improvement.

[Intracerebral radiotherapy under stereotaxic conditions]

Stereotactic radiosurgery is used for treating several brain diseases. Radiosurgery is a non-invasive alternative to surgery for brain metastases, and randomized trials are on going to assess the role of radiosurgery. Radiosurgery has been advocated for patients with small benign meningioma or with vestibular schwannoma, but there is no proof of efficacy and safety of radiosurgery in comparison with other treatments. Radiosurgery can obliterate 80-90% of small arteriovenous malformations, but no information exists on the survival of treated compared with untreated patients. The limited information available suggests that radiosurgery should be fully evaluated in well-designed prospective studies.

[Gross tumor volume and clinical target volume in radiotherapy: bone metastasis]

Bone is one of the three most favored sites of solid tumor metastasis. Skeletal metastasis may be identified by four clinical imaging methods: plain film radiography, computed tomography scanning, radioisotope scanning, and magnetic resonance imaging. The dose per fraction, total dose, and anatomic distribution of the radiation (dosimetry) are important factors in determining the efficacy and normal tissue tolerance to radiotherapy. Controversies about fractionation of palliative radiotherapy for bone metastasis are steel ongoing. The most commonly used schedules are a single treatment of 8 Gy, 30 Gy in 10 fractions and 20 Gy in 5 fractions. Treatment volumes and safety margins depend on the location and the extent of the bone metastasis, and are also determined by the symptoms felt by the patient.

Shifting of localization planes in optical testing: application to a shearing interferometer

An amplitude-division two-beam interferometer illuminated by a quasi-monochromatic, spatially incoherent, and periodic source yields multiple localization planes of interference fringes. If a thick transmission sample with a few localized phase disturbances in various layers is placed in the interferometer, the disturbances in a layer can be detected, making its images through the two arms coincide with a chosen localization plane. Different layers can be analyzed by means of shifting the localization plane by a variation of the source period without any other changes in the device. Here we illustrate this method by applying it to a shearing interferometer, a classical Wollaston prism placed between crossed polarizers. Experimental images of different observation planes are obtained, and they are in good agreement with the theoretical expectations.

Radiosurgery for re-irradiation of brain metastasis: results in 54 patients

PURPOSE

To evaluate in terms of probabilities of local-regional control and survival, as well as of treatment-related toxicity, results of radiosurgery for brain metastasis arising in previously irradiated territory.

PATIENTS AND METHODS

Between January 1994 and March 2000, 54 consecutive patients presenting with 97 metastases relapsing after whole brain radiotherapy (WBRT) were treated with stereotactic radiotherapy. Median interval between the end of WBRT and radiosurgery was 9 months (range 2-70). Median age was 53 years (24-80), and median Karnofski performance status (KPS) 70 (60-100). Forty-seven patients had one radiosurgery, five had two and two had three. Median metastasis diameter and volume were 21 mm (6-59) and 1.2 cc (0.1-95.2), respectively. A Leksell stereotactic head frame (Leksell Model G, Elektra, Instrument, Tucker, GA) was applied under local anesthesia. Irradiation was delivered by a gantry mounted linear accelerator (linacs) (Saturne, General Electric). Median minimal dose delivered to the gross disease was 16.2 Gy (11.8-23), and median maximal dose 21.2 Gy (14- 42).

RESULTS

Median follow-up was 9 months (1-57). Five metastases recurred. One- and 2-year metastasis local control rates were 91.3 and 84% and 1- and 2-year brain control rates were 65 and 57%, respectively. Six patients died of brain metastasis evolution, and three of leptomeningeal carcinomatosis. One- and 2-year overall survival rates were 31 and 28%, respectively. According to univariate analysis, KPS, RPA class, SIR score and interval between WBRT and radiosurgery were prognostic factors of overall survival and brain free-disease survival. According to multivariate analysis, RPA was an independent factor of overall survival and brain free-disease survival, and the interval between WBRT and radiosurgery longer than 14 months was associated with longer brain free-disease survival. Side effects were minimal, with only two cases of headaches and two of grade 2 alopecia.

CONCLUSION

Salvage radiosurgery of metastasis recurring after whole brain irradiation is an effective and accurate treatment which could be proposed to patients with a KPS>70 and a primary tumour controlled or indolent. We recommend that a dose not exceeding 14 Gy should be delivered to an isodose representing 70% of the maximal dose since local control observed rate was similar to that previously published in literature with upper dose and side effects were minimal.

[Radiotherapy of brain astrocytomas and oligodendrogliomas of the adult]

Gliomas are moderately radiosensitive. The main prognostic factors are the anatomicopathological type and grade of glioma, the performance status, age of the patient and the extent of the surgery. According to data from the literature, high-grade gliomas should be given 60 Gy in five weekly fractions of 1.7 to 2 Gy in a volume including tumor or tumor bed, edema and a 2- to 3-cm margin. A dose of 45 Gy would be sufficient for low-grade gliomas, according to the results of a recent randomized EORTC trial. Brachytherapy and radiosurgery techniques may be indicated in selected cases.

Multilocalization and the van Cittert-Zernike theorem. 2. Application to the Wollaston prism

The van Cittert-Zernike theorem can be used to evaluate visibility at the exit of an amplitude-division interferometer with two-beam interferences. If the source illuminating the interferometer is a periodic array of slits, at the exit there is a sequence of localization surfaces. The formulas for the position and fringe spacing of the principal localization surfaces are applied to a Wollaston quartz prism, and there is good agreement between theoretical and experimental results. Moreover, the fringe localization depth and the intermediate localization surfaces obtained experimentally coincide with those predicted by theory.

Multilocalization and the van Cittert-Zernike theorem. 1. Theory

The complex degree of coherence and the resulting van Cittert-Zernike theorem are employed to analyze the exit of an arbitrary amplitude-division interferometer with two-beam interferences. Considering that the source is a periodic array of spatially incoherent slits and assuming negligible equivalent aberrations and no vignetting, an expression for the complex degree of coherence as a function of the position of an exit point is derived. Formulas for the location, fringe spacing, and fringe localization depth of the multilocalized fringes are given.

Comparison of double-contrast CT arthrography image quality with nonionic contrast agents: isotonic dimeric iodixanol 270 mg I/mL and monomeric iohexol 300 mg I/mL

RATIONALE AND OBJECTIVES

The authors evaluated the image quality on delayed CT arthrography images with the use of the nonionic dimeric contrast agent, iodixanol 270 mg I/mL, compared with iohexol 300 mg I/mL.

METHODS

A total of 132 patients with shoulder pain were included in a randomized, parallel, double-blind study. Sixty seven patients received iodixanol and 65 patients received iohexol. Patients underwent two CT-arthrography examinations: the first was performed 20 to 30 minutes after contrast injection and the second, 50 to 70 minutes after contrast injection. Data from 31 patients were excluded from the efficacy analysis. The overall quality of CT arthrography images was graded into four categories: excellent, good, moderate, and bad.

RESULTS

The overall quality of delayed CT arthrography images was significantly better in the iodixanol group (P = 0.001, alpha = 0.05). On the first CT examination, image quality was good or excellent in 88% of the cases in the iodixanol group and in 96.1% in the iohexol group. The results on the delayed CT arthrography examination indicated that image quality was good or excellent in 88% of the cases when iodixanol was used and in 63.5% when iohexol was used.

CONCLUSIONS

The overall quality of delayed images was significantly better with iodixanol than with iohexol.

[A quality reference manual for radiology]

The purpose of this article is to introduce a quality manual for radiology departments. A radiology department has implemented a quality improvement program since 1996. This manual was developed as a tool for quality improvement program. This manuscript, was based on foreign accreditation manuals as well as from French experiences and summarized. In addition, new criteria were added, especially in the field of interventional radiology. This reference book is first dedicated to the self-assessment of radiology departments. It can also be used for an external audit.

Treatment of malignant gliomas in the elderly

The benefit of standard treatment of malignant glioma in older patients is debated. In order to assess the effect of a combination of surgery, radiotherapy and chemotherapy on survival of elderly patients with high grade gliomas, 30 consecutive patients older than 70 years with malignant supratentorial gliomas were studied between 9/93 and 9/96. Median age was 73 years (70-79). The mean Karnofsky performance status (KPS) was 66 (30-100). Patients underwent maximum possible surgery, followed by a course of radiotherapy (45 Gy/25 fractions/5 weeks) with 3 or 4 orthogonal beams and a 2 cm margin around the tumor bed. The administration of chemotherapy was left at the discretion of the responsible physician and 12 patients received reduced dose nitrosourea-based chemotherapy. The overall median survival was 36 weeks. The median time to progression was 26 weeks. Three months after surgery, 26 patients were alive, 5 were in complete response, 2 in partial response and 10 were stabilized. Preradiotherapy KPS was the only significant prognostic factor with a median survival of 40 weeks in patients with KPS > or = 70 and 25 weeks when KPS was < 70 (logrank test, p = 0.05). In responding and stable patients (57% of the group) the median KPS was 68 and 66 at 1 and 3 months after the completion of radiotherapy. There was no case of radiotherapy-induced dementia with this regimen. Four out of 12 patients who received chemotherapy, experienced WHO grade 3/4 hematotoxicity. This study suggest that some patients older than 70 years with KPS > or = 70 may benefit from the treatment of malignant gliomas with surgery followed by reduced dose of limited field radiotherapy. Further studies are needed to define the most appropriate dose of radiotherapy and to evaluate further the risk/benefit ratio of a reduced dose chemotherapy in this population.

How to optimize therapeutic ratio in brachytherapy of head and neck squamous cell carcinoma?

Considerable experience has been accumulated with low dose rate (LDR) brachytherapy in the treatment of squamous cell carcinoma of the oral cavity and oropharynx, 4 cm or less in diameter. Recent analysis of large clinical series provided data indicating that modalities of LDR brachytherapy should be optimized in treating these tumours for increasing therapeutic ratio. LDR brachytherapy is now challenged by high dose rate (HDR) brachytherapy and pulsed dose rate (PDR) brachytherapy. Preliminary results obtained with the last two modalities are discussed in comparison with those achieved with LDR brachytherapy.