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It is well established that the formation of transthyretin (TTR) amyloid fibrils is linked to the destabilization and dissociation of its tetrameric structure into insoluble aggregates. Isotope labeling is used for the study of TTR by NMR, neutron diffraction, and mass spectrometry (MS). Here MS, thioflavin T fluorescence, and crystallographic data demonstrate that while the X-ray structures of unlabeled and deuterium-labeled TTR are essentially identical, subunit exchange kinetics and amyloid formation are accelerated for the deuterated protein. However, a slower subunit exchange is noted in deuterated solvent, reflecting the poorer solubility of non-polar protein side chains in such an environment. These observations are important for the interpretation of kinetic studies involving deuteration. The destabilizing effects of TTR deuteration are rather similar in character to those observed for aggressive mutations of TTR such as L55P (associated with familial amyloid polyneuropathy)., (© 2016 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)

Primary angiosarcoma is a rare type of breast cancer, the diagnosis is difficult to establish and it has the worst prognostic of all breast malignancies. Two cases of primary breast angiosarcoma have been observed at the centre Henry Kaplan of Tours and at the hospital La Source of Orleans since 2001. Based on a literature review, we analyse the epidemiological, pathological, clinical, diagnostic and treatment aspect of this type of cancer. Mastectomy is the reference treatment and the benefit of radiotherapy and chemotherapy remains to be demonstrated.

Purpose: In 1996, a multicenter randomized study was initiated that compared sequential vs. concurrent adjuvant chemotherapy (CT) with radiation therapy (RT) after breast-conserving surgery (ARCOSEIN study). After a median follow-up of 6.7 years (range, 4.3-9 years), we decided to prospectively evaluate the late effects of these 2 strategies., Methods and Materials: A total of 297 patients from the 5 larger participating institutions were asked to report for a follow-up examination. Seventy-two percent (214 patients) were eligible for evaluation of late toxicity. After breast-conserving surgery, patients were treated either with sequential treatment with CT first followed by RT (Arm A) or CT administered concurrently with RT (Arm B). In all patients, CT regimen consisted of mitoxantrone (12 mg/m2), 5-FU (500 mg/m2), and cyclophosphamide (500 mg/m2), 6 cycles (Day 1 to Day 21). Conventional RT was delivered to the whole breast by administration of a 2 Gy per fraction protocol to a total dose of 50 Gy (+/- boost to the primary tumor bed). The assessment of toxicity was blinded to treatment and was graded by the radiation oncologist, according to the LENT/SOMA scale. Skin pigmentation was also evaluated according to a personal 5-points scoring system (excellent, good, moderate, poor, very poor)., Results: Among the 214 evaluable patients, 107 were treated in each arm. The 2 populations were homogeneous for patient, tumor, and treatment characteristics. Subcutaneous fibrosis (SF), telangectasia (T), skin pigmentation (SP), and breast atrophy (BA) were significantly increased in Arm B. No statistical difference was observed between the 2 arms of the study concerning Grade 2 or higher pain, breast edema, or lymphedema. No deaths were caused by late toxicity., Conclusion: After breast-conserving surgery, the concurrent use of CT with RT is significantly associated with an increase incidence of Grade 2 or greater late side effects.

Context: The A "Standards, Options and Recommendations A" (SOR) project, started in 1993, is a collaboration between the Federation of French Cancer Centres (FNCLCC), the 20 French regional cancer centres, and specialists from French public universities, general hospitals and private clinics. The main objective is the development of clinical practice guidelines to improve the quality of health care and the outcome of cancer patients. The methodology is based on a literature review and critical appraisal by a multidisciplinary group of experts, with feedback from specialists in cancer care delivery., Objective: To update the SOR recommendations for the use of radiation therapy in the management of patients with osteosarcoma. This work was performed in collaboration with the French society against cancers in children and adolescent (SFCE)., Methods: Data have been identified by literature search using MedlineA (from January 1992 to October 2003). In addition several Internet sites were searched in October 2003., Results: The 3 mains standards are: 1) local and exclusive curative irradiation is not indicated as primary treatment for osteosarcoma or for local and operable recurrence, except for lesion in inaccessible sites or if the patient refuses surgery; 2) local and prophylactic adjuvant irradiation is not indicated for the treatment of osteosarcoma after chemotherapy (neoadjuvant and/or adjuvant) and complete macro or microscopic surgery, except for nonoperable R1 or R2 surgical resection and 3) whole-lung prophylactic irradiation is not indicated in non-metastatic osteosarcoma. Systemic metabolic radiotherapy for pain treatment, using samarium-153 ethylene diamine tetramethylene phosphonic acid (Sm-153-EDTMP) can be offered to patients with painful metastatic osteosarcoma or in case of recurrent bone sites inaccessible to local therapies (surgery, external irradiation).

SècheThis paper is devoted to the study of the molecular basis of the boron neutron capture enhancement of fast-neutron radiotherapy. Plasmid DNA was irradiated with a medical fast-neutron beam in the presence of either (10)B or (11)B. The number of induced SSBs and DSBs was much higher in samples containing (10)B compared to (11)B. The additional breaks are attributed to the nuclear reaction (10)B(n, alpha)(7)Li induced by the capture by (10)B of thermal neutrons produced in the medium by scattering and slowing down of neutrons. Irradiation in the presence of DMSO (OH radical scavenger) allows the number of nonscavengeable breaks to be determined. The ratio DSB/SSB is within the range of those observed with heavy ions, in good agreement with the hypothesis that the additional breaks are due to alpha particles and recoil lithium nuclei. The simulation of the energy deposition along the paths of the alpha and (7)Li particles allows the calculation of core and penumbra track volumes. Further, the number of plasmids encountered by the core and the penumbra was evaluated. Their number was compared to the nonscavengeable additional breaks. Since the two sets of values are of the same order of magnitude, we conclude that the nonscavengeable additional SSBs and DSBs could be due to direct effects.

Among high linear energy transfer (LET) irradiations techniques, those using fast neutrons are able to eradicate glioblastoma cells. At least a 13 grays (Gy) irradiation dose has to be used, but high morbidity is observed in case of over 11 Gy irradiation. So, no therapeutic windows have been found despite the fact that more than 900 patients were included in clinical trials. Boron neutron capture therapy (BNCT) uses alpha emitting nuclear reactions, produced within tumoral cells by boron neutron captures. (10)B is specifically loaded inside tumoral cells via a boronated molecule, and the tissues are then irradiated with thermal or epithermal neutrons. Although this type of irradiation is yet considered as a regular method in Japan, USA and Europe have started clinical trials, currently in progress, in order to define the BNCT place in the post-operative care of high grade glioma. Non-removable tumors may benefit from boron neutron capture enhancement of fast neutron irradiation, i.e. the combination of these two methods. Preliminary studies show that a "biological" dose enhancement of 20 % could be obtained within the tumor when a concentration of 100 microg/g of (10)B is targeted into it. These concentrations are achievable by intra-arterial administration of (10)boronophenylalanine (BPA) or borosulfhydryl (BSH). Recently, some publications have also demonstrated that the thermal neutron flux yielded within the irradiated tissues could be increased. Clinical trials, using this technique, are planned in USA and Europe.

Purpose: Retrospective study to analyze the results of external beam radiation treatment with or without surgery for loco-regional recurrence of adenocarcinoma of the rectum following previous surgery without pre- or post-operative radiotherapy., Patients and Methods: Between March 1973 and November 1991, 211 patients with loco-regional recurrence of rectum cancer were treated with external beam radiation treatment. Radical surgery was the only initial treatment modality. Surgical resection of local recurrence was done in 36 patients and only 17 patients could undergo complete resection. Forty-seven patients underwent radiotherapy (RT) combined with surgery and 164 received external beam radiation treatment alone to a mean total dose of 46 Gy., Results: Among the 151 patients whose recurrence was revealed by pain, 64 (42%) were considered to have a complete symptomatic response after loco-regional treatment with radiosurgery or RT alone. The mean duration of response was 12 months. The 3-year overall survival rate was 16%. Five prognostic factors decreased the overall survival rate in multivariate analysis: high age, sex (male), concomitant distant metastasis, no tumor resection, and low total radiation dose with external beam radiation treatment alone. The 3-year overall survival rate for patients with completely resected recurrences was 39%., Conclusion: External beam RT treatment can only be considered a palliative symptomatic treatment. New techniques of early detection of local recurrence and new combined modalities approaches (radiation sensitizers or intra-operative radiotherapy) with surgical resection in some favorable cases should be studied.

The purpose was to evaluate the use of the CT option for simulator during a 14-month period in the radiotherapy department. The CT option has been adapted on the Philips simulator SL23. The virtual tunnel diameter is 92 cm which allows slice acquisition regardless of the contention device used. This system is connected to the treatment planning system through an Ethernet link. Three fields of view are available which cover the standard radiotherapy use. Four hundred and twenty-seven patients benefited from this system over a 14-month period of use. The number of slices acquired per patient regularly increased. The use of the system was rapidly extended to all the standard treatments. Those slices were also used as additional information for these high technology treatments. The good quality of the images and the reliability of this system involved a rapid integration in the treatment preparation procedure. It will not replace the use of the scanner but will significantly improve the treatment quality.

The clinical and pathological features of 4 cases of cutaneous neuroendocrine carcinoma are reported. There are unusual malignancies mostly observed in elderly, the prognosis is poor by loco-regional aggressivity and disseminated metastases. They are diagnosed by a pathologist: ultrastructural studies and immunohistochemistry support the diagnosis. A combination of a wild local excision, node dissection and post-operative radiation is recommended.

Radiobiological data indicate that fast neutrons could bring a benefit in the treatment of some tumour types, and suggest mechanisms through which this benefit could be achieved. However, radiobiology also clearly indicates that there is a need for patient selection as well as for a high-physical selectivity. The main difficulty when interpreting the results of neutron therapy are the poor technical conditions in which the first treatments were applied. This explains why the value and the place of neutron therapy are not universally recognized, although more than 15,000 patients have been treated so far worldwide. There are, however, clinical indications of fast neutrons bringing a benefit for the following tumour sites: salivary glands, paranasal sinuses, soft tissue sarcomas, prostatic adenocarcinomas, palliative treatment of melanoma and rectum. These tumours represent about 10-15% of all patients currently referred to the radiation therapy departments.

The first neutron beam at the Orleans neutron therapy facility was produced in 1980 through a target and collimator designed by C.G.R MeV. Technical investigations have led to some appreciable improvements for beam penetration and collimation. We report the main characteristics of the irradiation facility in 1988.