Recommandations pour le contrôle de qualité en curiethérapie

Brachytherapy consists of sealed radioactive source implantation. The diversity in the nature of radioelements, in their energy and activity requires strict implantation and utilization rules. These rules include radioactive source physical parameters check, after-loading machine and treatment planning system quality assurance and safe and reproducible dosimetric systems. Patient and medical workers information guarantee radioprotection and prevention of accidental exposures.     

Sécurité de l’information en centre de radiothérapie : contrôler ses risques pour mieux y faire face

The dematerialization of data, the multiplication of sharing and exchanges between professionals, the increase of business software offer (patient files, human resources management, financial management, document management, etc.) question us about the security of information systems. This protection contributes to the quality of the care of patients in respect of their rights, to ensure the confidentiality, traceability and sustainability of digital personal health data and to strengthen the confidence of professionals in the system and its uses. But what security procedures are currently being undertaken in the radiotherapy centres?     

Complément de dose de protons pour les cancers du nasopharynx localement évolués : une expérience de l’institut Curie

PurposeThe aim of this study was to assess the treatment outcome and toxicity for patients with locally advanced nasopharyngeal carcinoma treated with a complementary dose with proton.Patients and methodsBetween November 1999 and September 2016, 17 patients have been treated for a stage III–IVa nasopharyngeal carcinoma in the proton therapy centre of Curie Institute. Bilateral lymph node in the neck (I–V levels) received from 40 to 54 Gy with photon beam. The primary tumor volume including microscopically extensions received a complementary dose with proton in order to reach the dose of 70 to 78 Gy. All the patients received a concomitant chemotherapy. The end-points of the study were loco-regional control, survival, and treatment-related toxicity.ResultsPatients characteristics were: median age 49, 71 % male, 88% stage IVa, with a majority (82%) of T4N0M0. The median follow-up was 99 months. The 2-, 5- and 10-year actuarial locoregional free survival and overall survival were 94% and 88%, 86% and 74%, and 86% and 66%, respectively. The grade ≥ 3 late adverse events were sphenoid bone radionecrosis (5.9%) and hearing loss (23.5%).ConclusionThis study showed that a complementary dose with proton seems to be a good option for the treatment of locally advanced nasopharyngeal carcinoma, particularly for T4N0M0.     

Place de la radiothérapie pour les lymphomes du mucosa-associated lymphoid tissue gastriques : résultats d’une étude rétrospective

Purpose

We aimed to evaluate therapeutic results of radiotherapy for gastric mucosa-associated lymphoid tissue (MALT) lymphomas.

Le contrôle de la respiration en radiothérapie

Background and purpose

The use of centimetric margins to cover the target movements influenced by the breathing create an important irradiation. Some radiotherapies may be improved applying a breathing control.

Material and methods

Breathing control essentially involves any of three techniques and two methods. Breath hold or synchronization have to be implemented regarding to the expected improvements.

Clinical objectives

Lung, liver and breast sites have specific constraints. Lung radiotherapy is optimized when sparing healthy parenchyma with inspiration. Left breast radiotherapy often needs to protect the heart pushed out of the irradiation fields with inspiration. The liver is the most complex site where all methods have the same low precision.

Conclusions

Breathing control during radiotherapy brings important dosimetric improvements. The results of current clinical trials will help to confirm the potential benefit.     

Curiethérapie prostatique de rattrapage : solution pour les rechutes localisées après irradiation ?

Salvage brachytherapy after a first prostate radiation therapy is an emerging technique, which has to be considered in the therapeutic armamentarium in the clinically challenging context of patients with isolated local failure from prostate cancer who may still be considered for cure. These occult failures are more and more frequently diagnosed at an early stage, thanks to targeted biopsies and advances in imaging modalities, such as multiparametric MRI and PET-CT. Salvage brachytherapy benefits from the implantation accuracy of brachytherapy procedures using 3D dosimetry and has resulted in more than 50% tumour control rates with long-term. Incontinence rates are always below those of other salvage treatments such as radical prostatectomy, HIFU or cryotherapy. Today, a consensus has been reached to better define good candidates for salvage brachytherapy with respect to disease characteristics at baseline and at failure. No consensus has been clearly defined yet regarding the choice of the technique (low or high dose rate), the total dose to be delivered, or the volume to be implanted (whole gland or focal). While we await robust data from recently completed phase II studies and given the heterogeneous results in the literature, this technique (although already included in the last 2016 NCCN guidelines) remains to be precisely evaluated, optimally within the frame of controlled trials.     

De la construction du bunker à la prise en charge du patient : contrôles qualité des techniques modernes de radiothérapie

Installation and use of a new radiotherapy device require an adequate quality and safety policy. The process leading to the commissioning of an accelerator following the construction of a bunker includes, among other tasks, the installation of the accelerator, the verification of compliance with the specifications, the signature of the acceptance specification as well as the process of characterization and modeling of the accelerator before its clinical use. The emergence of modern radiotherapy techniques, such as intensity modulated conformational radiotherapy and stereotactic radiotherapy, has resulted in more complex quality controls. The purpose of this article is to explain the different stages of the implementation of innovative radiotherapy techniques and to specify their features.     

Développement d’une procédure de contrôle de qualité externe des faisceaux du CyberKnife : étude préliminaire multicentrique

PurposeTo develop an external quality control procedure for CyberKnife^® beams. This work conducted in Nancy, has included a test protocol initially drawn by the medical physicist of Nancy and Lille in collaboration with Equal-Estro Laboratory.Materials and methodsA head and neck anthropomorphic phantom and a water-equivalent homogeneous cubic plastic test-object, so-called “MiniCube”, have been used. Powder and solid thermoluminescent dosimeters as well as radiochromic films have been used to perform absolute and relative dose studies, respectively. The comparison between doses calculated by Multiplan treatment planning system and measured doses have been studied in absolute dose. The dose distributions measured with films and treatment planning system calculations have been compared via the gamma function, configured with different tolerance criteria.ResultsThis work allowed, via solid thermoluminescent dosimeter measurements, verifying the beam reliability with a reproducibility of 1.7 %. The absolute dose measured in the phantom irradiated by the seven participating centres has shown an error inferior to the standard tolerance limits (±5 %), for most of participating centres. The relative dose measurements performed at Nancy and by the Equal-Estro laboratory allowed defining the most adequate parameters for gamma index (5 %/2 mm – with at least 95 % of pixels satisfying acceptability criteria: γ < 1). These parameters should be independent of the film analysis software.ConclusionThis work allowed defining a dosimetric external quality control for CyberKnife^® systems, based on a reproducible irradiation plan through measurements performed with thermoluminescent dosimeters and radiochromic films. This protocol should be validated by a new series of measurement and taking into account the lessons of this work.     

Prise en charge adjuvante des cancers invasifs du sein : les techniques de radiothérapie modifient-elles les taux de contrôle local et de survie ?

Conventional radiotherapy (RT) in breast cancer treatment includes a total dose of 50 Gy with a 16 Gy-boost in a smaller volume. After mastectomy, radiotherapy of all node-positive patients seems to be applied whatever the positive node number. Modulation of RT technique uses the fraction dose, namely through accelerated hypofractionation regimen in a constant volume. A group of patient with a low risk of recurrence may benefit from this technique. In a smaller irradiated volume, accelerated hypofractionation still belongs to intensive clinical research evaluating intraoperative RT, brachytherapy, Mammosite, and external partial breast irradiation. Intensity-modulated radiotherapy decreases the risk of moist desquamation. The development of the gating offers greater protection of certain critical organs including lung, heart, and chest/ribs. Finally, predictive tests identifying patients at high risk of developing late effects led us to adapt RT technique to some of them and therefore increase long term therapeutic ratio.     

Psychothérapie de la dignité: une intervention pour réduire la détresse psychologique chez les personnes en soins palliatifs

This study examined the feasibility of the introduction of a new intervention, dignity therapy, in a palliative care setting and evaluated the satisfaction of the participants regarding this intervention. This intervention was administered to 33 French-speaking persons attending a palliative care center in Quebec City. Results confirmed the relevance of this intervention and showed that it is associated with a high-level of satisfaction for participants and family members.     

Association de radiothérapie externe et de curiethérapie pour les cancers de la prostate

Brachytherapy as sole treatment is standard of care for D’Amico classification low-risk prostate cancer. For intermediate and high-risk patients, brachytherapy can be associated to external beam radiation therapy to better take into account the risk of extracapsular effraction and/or seminal vesicle involvement. Three randomized studies have shown that this association increases freedom from relapse survival compared to exclusive external beam radiation therapy. This benefit is not shown for overall survival. The addition of a hormonal therapy to this association is most likely mandatory for high-risk patients, and needs to be confirmed for intermediate risk patients. Both high-dose rate and low-dose rate brachytherapy are suitable with similar biochemical disease free survival rates. High-dose rate brachytherapy seems to have a better genitourinary tolerance profile, while low-dose rate brachytherapy is an easier process and has a more widespread expertise.     

Précarité psychosociale et impact sur le cancer: pour une approche différentielle des logiques subjectives

Current clinical practice in public hospitals presupposes that encountered patients are often not included in a social network, with a poor, weakened, or even completely compromised economic background. It is mainly the case of institutions that bear a historical identity of “refuge hospital” such as our University Hospital Centre St-Pierre, Brussels, Belgium. We find patients who are isolated and/or exiled; in addition, illegal situation, drug addiction, and general negligence are frequently found in their history. These clinical patterns have been thus wholly removed from the social services that have been intended to provide. From a psychopathological point of view, it is patently clear that we see clinical variations, including psychosis (acutely progressive or well-compensated psychosis), that were previously handled by psychiatry or with a smoldering evolution (via social services, and sometime by the individual himself) as a problematic limiting factor from social integration point of view. In a work context, within the service of hematooncology, our research puts clinical practice to the test with a differential approach (for psychosis and neurosis) to attempt to identify variables following diagnostic practices in cancer patients. We present our theoretical and clinical orientation, from psychoanalytical and differential perspectives, as well as our methodology focusing on schizophrenia through the presentation of case studies.