Fractionated Stereotactic Radiation Therapy for Pituitary Adenomas: An alternative escalating protocol of hypofractionated stereotactic radiotherapy delivering 35Gy in 5 fractions

PURPOSE: Evaluate efficacy and toxicity of hypofractionated stereotactic radiotherapy (HSRT) for patients treated for pituitary adenoma (PA) with an alternative HSRT escalating protocol delivering 35Gy in 5 fractions. MATERIAL AND METHODS: From June 2007 to March 2017, 29 patients with pituitary adenoma were treated in Antoine Lacassagne Cancer Centre with an alternative HSRT protocol. Prescribed dose was 35Gy in 5 fractions of 7Gy. Radiographic responses were assessed by annual MRI. Hormone blood samples were evaluated each year after HSRT. RESULTS: A total of 29 patients aged between 23 and 86 years (median 54 years) were included. Twelve patients received HSRT for recurrent cases and 12 received postoperative adjuvant HSRT, 5 patients did not have surgery. After a median follow-up period of 47 months local control rate was 96%. One patient presented an out-field tumor regrowth 73 months after HSRT. The majority of PA were endocrine-active (18 patients, 62%). After HSRT, 8 patients (44%) presented complete response on initial secretion, 4 patients (23%) presented partial response on initial secretion. Four patients (14%) presented grade 2 or more acute radiation toxicities. One grade 4 visual disorder was observed for one patient. CONCLUSIONS: HSRT delivering 35Gy in 5 fractions represents a feasible treatment and shows promising results to reduce hormonal overproduction and to improve local control in PA

Diffusion and perfusion weighted magnetic resonance imaging for tumor volume definition in radiotherapy of brain tumors

Abstract Accurate target volume delineation is crucial for the radiotherapy of tumors. Diffusion and perfusion magnetic resonance imaging (MRI) can provide functional information about brain tumors, and they are able to detect tumor volume and physiological changes beyond the lesions shown on conventional MRI. This review examines recent studies that utilized diffusion and perfusion MRI for tumor volume definition in radiotherapy of brain tumors, and it presents the opportunities and challenges in the integration of multimodal functional MRI into clinical practice. The results indicate that specialized and robust post-processing algorithms and tools are needed for the precise alignment of targets on the images, and comprehensive validations with more clinical data are important for the improvement of the correlation between histopathologic results and MRI parameter images

Tumeurs cérébrales pédiatriques : revue de la littérature en radiothérapie, état de l’art et défis pour l’avenir en ce qui concerne la protonthérapie et la carbonethérapie

International audienceBackground and purposeBrain tumours are the most frequent solid tumours in children and the most frequent radiotherapy indications in paediatrics, with frequent late effects: cognitive, osseous, visual, auditory and hormonal. A better protection of healthy tissues by improved beam ballistics, with particle therapy, is expected to decrease significantly late effects without decreasing local control and survival. This article reviews the scientific literature to advocate indications of protontherapy and carbon ion therapy for childhood central nervous system cancer, and estimate the expected therapeutic benefits.Materials and methodsA systematic review was performed on paediatric brain tumour treatments using Medline (from 1966 to March of 2014). To be included, clinical trials had to meet the following criteria: age of patients 18 years or younger, treated with radiation, and report of survival. Studies were also selected according to the evidence level. A secondary search of cited references found other studies about cognitive functions, quality of life, the comparison of photon and proton dosimetry showing potential dose escalation and/or sparing of organs at risk with protontherapy; and studies on dosimetric and technical issues related to protontherapy.ResultsA total of 7051 primary references published were retrieved, among which 40 clinical studies and 60 papers about quality of life, dose distribution and dosimetry were analysed, as well as the ongoing clinical trials. These papers have been summarized and reported in a specific document made available to the participants of a final 1-day workshop. Tumours of the meningeal envelop and bony cranial structures were excluded from the analysis. Protontherapy allows outstanding ballistics to target the tumour area, while substantially decreasing radiation dose to the normal tissues. There are many indications of protontherapy for paediatric brain tumours in curative intent, either for localized treatment of ependymomas, germ-cell tumours, craniopharyngiomas, low-grade gliomas; or panventricular irradiation of pure non-secreting germinoma; or craniospinal irradiation of medulloblastomas and metastatic pure germinomas. Carbon ion therapy is just emerging and may be studied for highly aggressive and radioresistant tumours, as an initial treatment for diffuse brainstem gliomas, and for relapse of high-grade gliomas.ConclusionBoth protontherapy and carbon ion therapy are promising for paediatric brain tumours. The benefit of decreasing late effects without altering survival has been described for most paediatric brain tumours with protontherapy and is currently assessed in ongoing clinical trials with up-to-date proton devices. Unfortunately, in 2015, only a minority of paediatric patients in France can receive protontherapy due to the lack of equipment.ObjectifsLes tumeurs cérébrales sont l’indication de radiothérapie pédiatrique la plus fréquente, avec des effets tardifs fréquents : cognitifs, osseux, visuels, auditifs et hormonaux. En raison de leur balistique exceptionnelle, les faisceaux de particules pourraient apporter une meilleure protection des tissus sains sans diminuer le contrôle local et la survie. Cet article est une revue de la littérature scientifique ayant pour but de proposer les indications de protonthérapie et de thérapie par ions carbone pour les tumeurs cérébrales pédiatriques et d’estimer les bénéfices thérapeutiques escomptés.Matériel et méthodesUne revue systématique a été réalisée sur les essais cliniques de radiothérapie des tumeurs pédiatriques en utilisant Medline (de 1966 à mars 2014), selon les critères suivants : patients âgés de 18 ans ou moins, ayant reçu une radiothérapie et comportant des données de survie. Les études sur les fonctions cognitives, la qualité de vie, la comparaison dosimétrique photons–protons ont également été incluses.RésultatsSur 7051 références primaires publiées, 40 études cliniques et 60 articles de qualité de la vie et dosimétrie ont été analysés, ainsi que les essais cliniques en cours. Ces documents ont été condensés et présentés dans un document spécifique mis à la disposition des experts participant à un atelier final d’une journée. Il existe de nombreuses indications de protonthérapie pour les tumeurs cérébrales pédiatriques à visée curative : pour le traitement localisé des épendymomes, tumeurs germinales, craniopharyngiomes, gliomes de bas grade, pour l’irradiation pan-ventriculaire des germinomes purs non-sécrétant et pour l’irradiation crâniospinale des médulloblastomes et germinomes purs métastatiques. La thérapie par ions carbone est en train d’émerger et pourrait être étudiée pour les tumeurs très agressives et radiorésistantes, tels les gliomes du tronc cérébral diffus, et les rechutes des gliomes de haut grade.ConclusionPour les tumeurs cérébrales pédiatriques, protonthérapie et thérapie par ions carbone sont prometteuses. L’avantage de diminuer les effets tardifs sans altérer la survie a été décrit pour la plupart des tumeurs cérébrales pédiatriques avec la protonthérapie et est en évaluation dans des essais cliniques en cours. Actuellement, en France, une minorité de patients pédiatriques reçoit une protonthérapie en raison du manque d’équipement