Adolescents and Young Adults with Primary Brain Tumor: Description of the Care Pathway of Patients Diagnosed in Grenoble Between 2013 and 2019.

Purpose: This study was undertaken to describe the Adolescents and Young Adults' (AYA-aged patients') neuro-oncology care pathways at Grenoble Alpes University Hospital according to the French health recommendations. Methods: A retrospective monocentric observational study was conducted between 2020 and 2021, on patients 13-29 years of age, diagnosed from January 2013 to 2019 in our institute with a primary brain tumor, excluding meningiomas, schwannomas, and neurinomas. The detailed analysis took into account the type of care unit (adult or pediatric), whether or not a dedicated AYA support team was involved, and various pretherapeutic actions. Results: Sixty patients were included in this study. Three of the 9 key stages of the care process were completed regardless of the type of management. Management in a pediatric oncology department seems to improve multidisciplinary discussions and access to the AYA team. Collaboration with an AYA team seems to improve the recourse to pediatric advice and supportive care. Conclusions: Increased vigilance at all key steps as defined in the recommendations of the Directorate General of Healthcare Services would significantly improve the overall quality of care for this specific population. In the absence of a dedicated AYA hospitalization unit, interdisciplinary cooperation between the different professionals of the adult and pediatric services is essential, and the involvement of the AYA mobile team is a factor that favors links and exchanges and ultimately an overall improvement in patient care and life. We propose our vision of an ideal AYA neuro-oncology care pathway.

Toward Neuro-Oncologic Clinical Trials of High-Dose-Rate Synchrotron Microbeam Radiation Therapy: First Treatment of a Spontaneous Canine Brain Tumor.

PURPOSE: The high potential of microbeam radiation therapy (MRT) in improving tumor control while reducing side effects has been shown by numerous preclinical studies. MRT offers a widened therapeutic window by using the periodical spatial fractionation of synchrotron generated x-rays into an array of intense parallel microbeams. MRT now enters a clinical transfer phase. As proof of principle and cornerstone for the safe clinical transfer of MRT, we conducted a "first in dog" trial under clinical conditions. In this report, we evaluated whether a 3-dimensional conformal MRT can be safely delivered as exclusive radiosurgical treatment in animal patients METHODS AND MATERIALS: We irradiated a 17.5-kg French bulldog for a spontaneous brain tumor (glioma suspected on magnetic resonance imaging) with conformal high-dose-rate microbeam arrays (50-µm-wide microbeams, replicated with a pitch of 400 µm) of synchrotron-generated x-rays. The dose prescription adjusted a minimal cumulated valley dose of 2.8 Gy to the plnning target volume (PTV) (cinical target volume (CTV)+ 1 mm). Thus, each beam delivered 20 to 25 Gy to the target as peak doses, and ∼1 Gy as valley doses RESULTS: The treatment was successfully delivered. Clinical follow-up over 3 months showed a significant improvement of the dog's quality of life: the symptoms disappeared. Magnetic resonance imaging, performed 3 months after irradiation, revealed reduction in tumor size (-87.4%) and mass effect with normalization of the left lateral ventricle. CONCLUSIONS: To our knowledge, this neuro-oncologic veterinary trial is the first 3-dimensional conformal synchrotron x-ray MRT treatment of a spontaneous intracranial tumor in a large animal. It is an essential last step toward the clinical transfer of MRT in the near future to demonstrate the feasibility and safety of treating deep-seated tumors using synchrotron-generated microbeams.