[Lung dose constraints for normo-fractionated radiotherapy and for stereotactic body radiation therapy]. / Doses aux organes à risque en radiothérapie conformationnelle et en radiothérapie stéréotaxique : les poumons.

Radiation-induced lung disease (RILD) is common after radiation therapy and represents cornerstone toxicities after treatment of thoracic malignancies. From a review of literature, the objective of this article was to summarize clinical and non-clinical parameters associated with the risk of RILD in the settings of normo-fractionated radiotherapy and stereotactic body radiation therapy (SBRT). For the treatment of lung cancers with a normo-fractionated treatment, the mean lung dose (MLD) should be below 15-20Gy. For a thoracic SBRT, V20Gy<10% and MLD<6Gy are recommended. One should pay attention to central tumors and respect specific dose constraints to the bronchial tree. The recent technological improvements may represent an encouraging way to decrease lung toxicities. Finally, our team developed a calculator in order to predict the risk of radiation pneumonitis.

[Practice evolution of hypofractionation in breast radiation therapy and medical impact]. / Évolution des pratiques médicales d'hypofractionnement en radiothérapie pour cancer du sein et impact économique.

PURPOSE: Whole breast irradiation after conservative surgery is the standard treatment for invasive breast cancer. Randomized studies indicate that hypofractionation can be equivalent for selected patients. This study focuses on fractionation practice evolution in a single centre, and analyses the economic impact of practice modification. MATERIAL AND METHODS: All prescriptions for invasive breast cancer between January 2010 and June 2014 were analyzed. Female patients 60 years or older, pN0 were considered for the economic study. Patients included in clinical trials or patient with high-grade tumours were excluded from the hypofractionation practice study, because physician could not choose fractionation. We used data from the Medical public health system to calculate cost per fraction and transportation cost. RESULTS: Two thousand thirty one patients were treated; 399 were eligible for the economic study (20%) and 282 for the practice study (14%). Treatment with 25 fractions decreased from 90% to 16% in the first half of 2014. Meanwhile, treatment with 15 or 16 fractions increased from 6% in 2010 to 68% in the first half of 2014. Hypofractionated treatment proportion was 100% with 42.5Gy in 16 fractions in 2010 and 100% 40Gy in 15 fractions in 2014, according to long-term follow-up publication of START trials. Treatment with five fractions remained stable around 7% (4 to 16%), reserved for patients over 80 years (P<0.0001). Based on data from 3451 fractions in 2013, transport cost was calculated at 62 € per fraction, in addition to a 170.77 € reimbursement per fraction, giving a cost per fraction of 232.77 €. CONCLUSION: Practice change led to an increase of hypofractionation in recent years. Hypofractionation may be currently prescribed and may concern 20% of patients. This practice evolution is beneficial for patients and the public health system.

Study by EXAFS of the local structure around Si on silicene deposited on Ag(1 1 0) and Ag(1 1 1) surfaces.

The local structure around the silicon atoms of silicene deposited onto Ag(1 1 0) and Ag(1 1 1) has been determined by extended x-ray absorption fine structure spectroscopy at the silicon K-edge. This study shows that silicon atoms are not in a flat honeycomb network locally buckled, but that this structure mimics the double Si(1 1 1)-plane of crystalline silicon with almost the same first and second interatomic distances (2.35 and 3.83 Å) on a regularly buckled geometry. Moreover the results evidence silver atoms at a well-defined distance from the silicon ones, a signature for an interaction between the silicene sheet and silver atoms released from the substrate.

Response to chemotherapy is not related to chromosome instability in synovial sarcoma.

BACKGROUND: Synovial sarcoma (SS) is an aggressive soft-tissue tumor. Despite being considered as a chemosensitive disease, the real impact of perioperative chemotherapy on metastasis-free survival (MFS) is controversial. We have shown that metastatic relapse of SS is strongly associated with genomic complexity. There are no data regarding the potential correlation between genomic complexity and response to chemotherapy. PATIENTS AND METHODS: The study population included 65 SS patients diagnosed between 1991 and 2013 and with available tissue material. Genomic profiling was carried out by using array-CGH. Forty-five SS out of the 65 patients were treated with neoadjuvant anthracycline/ifosfamide-based chemotherapy. Radiological response was assessed according to RECIST criteria. Histological response was defined by the percentage of recognizable tumor cells on the surgical specimen. RESULTS: Genomic complexity was significantly associated with MFS. However, there was no statistically significant association between radiological or histological response and genomic complexity. CONCLUSION: The absence of significant association between response to chemotherapy and genomic complexity suggests that the prognostic value of chromosome instability in SS is independent of response to chemotherapy; mechanisms leading to metastatic relapse of SS are intrinsic to the biology of the tumor and current cytotoxic drugs are only poorly efficient to prevent it.

[Postoperative radiation therapy for a patient with osteogenesis imperfecta: case report]. / Radiothérapie chez une patiente atteinte d'un cancer du sein et d'ostéogenèse imparfaite : à propos d'un cas.

Osteogenesis imperfecta is an unusual disease also called Lobstein disease. Characterized by abnormalities of collagen biosynthesis, a possible mutation on 17th chromosome is described. On the other hand, 29% of breast cancers present a mutation on the same chromosome. Nevertheless, the association of osteogenesis imperfecta and breast cancer is at the moment unknown. Therapeutic management is very difficult because of a loss in dihydropyrimidine dehydrogenase for patients having osteogenesis imperfecta, generating some toxicity by default in catabolism of 5-fluorouracil. We report the case of a 49-year-old woman with a breast cancer in the context of osteogenesis imperfecta. Dosimetric considerations permitting to reduce chess dose level have been performed for this patient. With a follow-up of 6 months, no imaging fracture has been revealed after radiotherapy. No evident conclusion about radiation injury from a case report could be described in case of osteogenesis imperfecta. To our knowledge, this is the first case which take into account potential radiation induced toxicities.

GROIN: a fast optical adjustment of a Kirkpatrick-Baez set-up.

A very simple and compact optical device aimed at the fast adjustment, alignment and bending of the mirrors of a Kirpatrick-Baez system used in the X-ray domain is described.

[Radiotherapy for soft tissue sarcomas of extremities. Preliminary comparative dosimetric study of 3D conformal radiotherapy versus helical tomotherapy]. / Radiothérapie postopératoire des sarcomes des tissus mous des extrémités. Etude dosimétrique préliminaire comparative de la radiothérapie conformationnelle avec la tomothérapie hélicoïdale.

PURPOSE: To evaluate dosimetry of helicoidal tomotherapy versus three-dimensional conformal radiotherapy (3D-CRT) with and without IMRT for the treatment of soft tissue sarcoma (STS) of the thigh. METHODS AND PATIENTS: A retrospective study was performed for three patients who received 3D-CRT as adjuvant radiation therapy for STS of the thigh. These three patients had a tumor in posterior, adductor or anterior compartment of the thigh. In each case, three treatments plans were optimised in tomotherapy, without bloc, with directional bloc and complete bloc of controlateral limb, to adequately treat the planning target volume and spare organ at risk. For each patient, we compare the three modalities of tomotherapy or "classical" IMRT from a clinac with the 3D-CRT actually performed for the treatment. RESULTS: Tomotherapy provides improved PTV coverage and dose homogeneity. This benefit was comparable in the three tomotherapy plans. The average D95% for tomotherapy and 3D-CRT were 97.6% and 94.8% respectively and the standard deviation is, at least, divided by two with conformal and is always better than performed with a clinac. The volume of the surrounding soft tissues receiving at least full prescription and hot spots, as evaluated by D2%, were significantly reduced in tomotherapy. Nevertheless, the results concerning the skin, the femur and the gonads were dependent on the tumor site in the thigh and not always improved with tomotherapy dosimetric studies. CONCLUSIONS: For this preliminary study, tomotherapy can provide better coverage and dose uniformity in PTV and minimize the volume of surrounding muscular tissues receiving high doses. However, in this study, there is no benefit for others OAR (skin, femur and gonads) except in particular constraint (for instance for a precise sparing of cutaneous or bony area). Other dosimetric studies, followed by prospective evaluations with long-term follow-up are needed to determine whether tomotherapy can improve outcome for patients with STS of the thigh.

Combining two structural techniques on the micrometer scale: micro-XAS and micro-Raman spectroscopy.

X-ray absorption and Raman spectroscopies are complementary in the sense that both give very precise information about the local structure of a sample, both are not restricted to crystalline materials, and in both cases the volumes of the material probed are similar. The X-ray technique has the advantage of being element- and orbital-selective, and sensitive to orientational effects owing to polarization selection rules. In many cases, however, its analysis can present some ambiguity. Combining the two techniques on a micrometer scale could therefore be a very powerful method structurally. In this paper the experimental set-up developed at the LUCIA beamline and its application to a natural mineral are described.

Unr, a cytoplasmic RNA-binding protein with cold-shock domains, is involved in control of apoptosis in ES and HuH7 cells.

Unr (upstream of N-ras) is a cytoplasmic RNA-binding protein involved in the regulation of messenger RNA stability and internal initiation of translation. We have used Unr-deficient murine embryonic stem (ES) cells to analyse Unr role in cell proliferation and response to stress. Disruption of both unr gene copies had no effect on ES cell proliferation. However, after ionizing radiation (IR), clonogenic survival of unr(-/-) ES cells was approximately 3-fold enhanced as compared to unr(+/+) cells. We further determined that IR-induced apoptosis was decreased in unr(-/-) ES cells, and that reintroduction of the unr gene in unr(-/-) cells restored normal IR-induced apoptosis. Three pro-apoptotic genes, p53, caspase-3 and Gadd45gamma, were downregulated in unr(-/-) ES cells, indicating that Unr, as other cytoplasmic RNA-binding proteins, regulates a complex genetic program, promoting cell death after IR. In contrast, in the human hepatoma cell line HuH7, Unr knockdown using unr-specific small interfering RNAs induced apoptosis, both in untreated and gamma-irradiated cells. Thus, our results establish that Unr acts as a positive or negative regulator of cell death, depending on the cell type. Manipulating the level of Unr may constitute a specific approach to sensitize cancer cells to anticancer treatments.

[Conservative and functional management for soft tissue sarcomas of the extremities: role of radiotherapy]. / Approche conservatrice et fonctionnelle dans les sarcomes des tissus mous des membres : place de la radiothérapie.

Recent publications have permitted to quantify the benefit of radiotherapy in the conservative treatment of soft tissue sarcoma of the limbs. The aim of this review is to focus on aspects of radiotherapy witch influence local control and functional outcome for early and late normal tissue damage. The evaluation of late effects is performed according to Soma-Lent (Subjective-Objective-Management-Analytic-Late Effects of Normal Tissues) classification. About complications, neurological complications are probably under estimated and are related to total dose of radiation therapy.

[Propositions for the selection and the delineation of peritumoral microscopic disease volumes in oral cavity and oropharyngeal cancers (lymph nodes excluded)]. / Proposition de sélection et délimitation des volumes cibles microscopiques péritumoraux dans les cancers de la cavité buccale et de l'oropharynx (aires ganglionnaires exclues).

This article reviews the concept of selectivity in peritumoral microscopic disease to be included in the Clinical Target Volume (CTV) for elective treatment for oral cavity and oropharyngeal squamous cell carcinoma, using the local tumoral spread. The objective of the present article is to present a procedure for the delineation of the target volumes, required for an appropriate application of 3-DCRT and IMRT for head and neck cancers. These propositions are for the delineation of microscopic peritumoral target volumes when external beam irradiation is required. CTVs are illustrated on CT sections.

[Adjuvant radiation therapy for soft tissue sarcoma of the extremities: analysis of local control according to volume and dose]. / Radiothérapie adjuvante des sarcomes des tissus mous des membres: analyse du contrôle local en fonction des volumes irradiés et de la dose.

PURPOSE: To evaluate retrospectively the anatomical definition of target volumes in the treatment of soft tissue sarcomas of the limbs and to study the radiation dose in the local control and toxicity. METHODS AND PATIENTS: Seventy-seven patients were consecutively treated for primary soft tissue sarcoma of the extremity with limb sparing surgery and external beam radiotherapy (EBRT) in the same institution. The median follow up was 56 months (17-89 months). RESULTS: Fifty-two patients (67%) had clear microscopic surgical margin (R0 resection), 23 (30%) had histologically positive microscopic margin (R1 resection), 2 had a macroscopic residual disease (R2 resection). An anatomical definition of target volumes has been realised. The mean dose was 50 Gy in 25 or 28 fractions; 23 patients received a boost restricted to the tumor bed: 13 with EBRT, 10 with brachytherapy (BRT). Thirty-four patients had an adjuvant chemotherapy. The overall 5 year local relapse rate was 10%. Seven local relapses were described, five of the high-grade tumours, and five in patients with positive margin. In univariate analysis, quality of surgery shows a significant effect for local control. By using LENT-SOMA scale for late toxicity, a significant difference was found for neurological complications for patients receiving a boost. CONCLUSIONS: The results of the series validate the concept of anatomical definition of the initial target volume. A boost should be realised for positive margin tumors and may be for high-grade tumors. Neurological toxicity must be considered for the evaluation of the prescribed dose.

[Comparison of intensity-modulated postoperative radiotherapy with conventional postoperative conformal radiotherapy for retroperitoneal sarcoma]. / Etude théorique d'une radiothérapie postopératoire avec modulation d'intensité d'un sarcome rétropéritonéal.

External postoperative radiation therapy for retroperitoneal sarcoma is an example of treatment using large fields for complex shaped volumes of irradiation. Prescribed dose is limited by tolerance of adjacent organs at risk (OAR). From a recent case treated by conventional conformal radiotherapy (3D-CRT), we evaluate the benefit of five theoretical IMRT plans. Criteria used are calculated from DVH related to delineated PTV and OAR. IMRT should permit to enhance the prescribed dose without increasing dose in the OAR (especially residual kidney, spinal cord and small bowel). This theoretical study show the feasibility of a dose escalation from a treatment dose of 45 Gy delivered by 3D-CRT up to a planning dose of 54 Gy calculated by IMRT with: for the PTV: an improvement of the dose homogeneity about 5% (range 2-6%) and moreover the coverage factor (CF) about 13% (range 9-16%); for the OAR: an improvement of the protection factor (PF) about 20% (range 11-24%); and thus an improved conformity index (CI = CF x PF) about 25% (range 15-32%).

Anchoring screening of defects interaction in a nematic liquid crystal.

The relaxation dynamic of a dipole of +1/2 and -1/2 parallel disclination lines in a confined geometry is measured. The confinement and the planar anchoring conditions force the disclinations to be normal to the glass plates. In a first asymptotic regime, the direct elastic interaction between disclination is completely screened out by the anchoring energy. In a second regime, corresponding to the final annihilation steps, the dynamic follows the square-root law predicted by de Gennes for two isolated and parallel disclinations. The annihilation dynamic, in the asymptotic regime, is in good agreement with an elastic model based on an electrostatic analogy.

[Surgical methods of removal of T4 nasopharyngeal malignancies. A preliminary report on 18 cases]. / Place de la chirurgie dans le traitement des cancers du cavum classés T4.

OBJECTIVES: To describe the technique and evaluate postoperative sequelae and results of transfacial surgical removal of T4N0 nasopharyngeal malignant neoplasms. MATERIAL AND METHODS: Eighteen cases of surgically-treated nasopharyngeal cancers, managed between january 1993 and october 2000, were retrospectively studied. Three patients were non-responders to neoadjuvant chemotherapy, 6 suffered local recurrence following standard treatment and 7 were operated first either because of a huge and osteolytic tumor or because of an uncommon histolopathology. RESULTS: Preoperative Vth nerve neuralgia (8 cases) was alleviated (4 cases) or cured (3 cases). At the time of diagnosis, ophthalmoplegia was observed in 3 cases. It disappeared postoperatively in 2 cases and after following radiation therapy in one. Median follow-up of the series was of 31.8 mths. Four patients were died of disease; one of them from distant metastases 4 years post-surgery. One patient is alive with distant metastases. The 13 last (72.2%) are alive without disease with a 35.6 mths median follow-up (6-77 mths). DISCUSSION: This short and heterogeneous series cannot lead to any evidence-based conclusion. But mid-term free-of-disease survival of 4 of the 5 patients suffering local recurrence and of patients presenting with so-called non-radiation-sensitive tumors is to be considered. In comparison with the high risk of neurological sequels following reirradiation, absence of specific toxicity of surgery observed in this series is to be underlined. CONCLUSION: In selected cases surgical treatment does not demonstrate any toxicity and is able to offer mid-term local control of the disease. Its role is to be evaluated further before inclusion in the therapeutic algorithm of these very bad prognosis-associated tumors.

Churg-Strauss syndrome in two patients receiving montelukast.

OBJECTIVE: Churg-Strauss syndrome (CSS) has been described in association with the treatment of asthmatic patients with leukotriene receptor antagonist. The main mechanism proposed to explain this condition is the unmasking of CSS after the leukotriene receptor antagonist has allowed corticosteroid tapering. Other hypotheses might be proposed. METHODS: We describe two patients who developed CSS after starting treatment with montelukast, a new antileukotriene drug. RESULTS: Both patients presented with CSS after 4-5 months of treatment with montelukast. Neither patient received long-term systemic steroids for asthma, but both were on inhaled steroids. One patient had a myocardial involvement and experienced a stroke. Our two patients were treated with systemic steroids and cyclophosphamide. CONCLUSIONS: CSS does not appear to relate to steroid tapering in our patients. The other hypotheses are a coincidence or a direct adverse effect of the antileukotriene. Long-term data on these drugs are lacking and leukotriene's role in vasculitis remains to be elucidated.

[Definitions of target volumes in soft tissue sarcomas of the extremities]. / Définition des volumes-cibles dans les sarcomes des tissus mous des extrémités.

Soft tissue sarcomas of the extremities are currently treated with more conservative and functional approaches, combining surgery, radiotherapy and chemotherapy. The role of external beam radiotherapy and brachytherapy has been defined through randomised studies performed in the 80's and 90's. However, the ubiquity of tumour location for these tumours makes difficult a systematic definition of local treatments. Tumour volume definition is based on pre and post surgical imaging (MRI) and on described pathological report. The clinical target volume will take into account quality of the resection and anatomical barriers and will be based on an anatomy and not only on safety margins around the tumour bed. General rules for this irradiation (doses, volumes) and principal results will be presented.

Surface X-ray absorption spectroscopy: principles and some examples of applications.

The application of X-ray spectroscopy to surface problems has started almost at the same time as that in materials science. While the theoretical bases are obviously the same, SEXAFS has some experimental peculiarities which are reviewed here. Some examples of this technique will then be given.

Memory-free conic anchoring of liquid crystals on a solid substrate

We show that the anchoring memory of liquid crystals on solid substrates can be completely removed by grafting highly mobile polymer chains. Using grafted polystyrene, we obtain uniform, stable, and reproducible memory-free and conically degenerated anchoring of the nematic 5CB. The symmetry of the conic anchoring enables two different zenithal anchoring breakings, towards homeotropic and planar states. Under external torques we observe both of them, with weak thresholds.

Sarcoma after radiation therapy: retrospective multiinstitutional study of 80 histologically confirmed cases. Radiation Therapist and Pathologist Groups of the Fédération Nationale des Centres de Lutte Contre le Cancer.

PURPOSE: To evaluate the best strategy for treatment of sarcoma that occurs after radiation therapy. MATERIALS AND METHODS: Records were retrospectively reviewed for 80 patients with a confirmed histologic diagnosis of sarcoma that occurred after radiation therapy performed during 1975-1995. The patients were treated for breast cancer (n = 33, 42%), non-Hodgkin lymphoma (n = 9, 11%), cervical cancer (n = 9, 11%), benign lesions (n = 4, 5%), or other tumors (n = 25, 31%). Sarcoma occurred after a mean latency of 12 years (range, 3-64 years), with most (70%) developing in the soft tissue. Treatment included surgery (28 patients), surgery and chemotherapy (18 patients), chemotherapy only (15 patients), and radiation therapy (14 patients). RESULTS: By the end of the study, 51 patients were dead, including 46 due to sarcoma. Median survival was 23 months. Overall survival rates at 2 and 5 years, respectively, were 69% and 39% for patients treated with surgery, 10% and 0% for those treated with chemotherapy, and 52% and 35% for those treated with surgery and chemotherapy (P =.001). The 2- and 5-year rates for survival without recurrence were 54% and 32%, respectively. CONCLUSION: The results confirm the beneficial effect of surgery. Further study is needed to explore the roles of combined treatments.