Segmentation automatique des images pour la planification dosimétrique en radiothérapie

International audienceL'essor de la radiothérapie conformationnelle et de la radiothérapie guidée par l'image a pour corollaire l'accroissement du temps consacré à la délinéation des volumes d'intérêt, qui est également le siège d'une variabilité inter et intraobservateur. Les développements informatiques et du traitement d'images ont permis des progrès dans l'automatisation partielle ou totale de ces tâches. Cet article détaille les grands principes de la segmentation d'images appliquée à la radiothérapie, ses applications ainsi que ses résultats les plus récents dans un contexte clinique

Stereotactic Body Radiation Therapy for the Management of Hepatocellular Carcinoma: Efficacy and Safety

This study aimed to describe patient characteristics, treatment efficacy, and safety in patients with hepatocellular carcinoma (HCC) undergoing stereotactic body radiation therapy (SBRT). We retrospectively analyzed data of 318 patients with 375 HCC treated between June 2007 and December 2018. Efficacy (overall survival [OS], relapse-free survival, and local control) and acute and late toxicities were described. The median follow-up period was 70.2 months. Most patients were treated with 45 Gy in three fractions. The median (range) PTV volume was 90.7 (2.6–1067.6) cc. The local control rate at 24 and 60 months was 94% (91–97%) and 94% (91–97%), respectively. Relapse-free survival at 12, 24, and 60 months was 62% (55–67%), 29% (23–36%), and 13% (8–19%), respectively. OS at 12, 24, and 60 months was 72% (95%CI 67–77%), 44% (38–50%), and 11% (7–15%), respectively. Approximately 51% and 38% experienced acute and late toxicity, respectively. Child-Pugh score B-C, high BCLC score, portal thrombosis, high GTV volume, and higher PTV volume reported on total hepatic volume ratio were significantly associated with OS. SBRT is efficient for the management of HCC with a favorable toxicity profile. The outcome is highly related to the natural evolution of the underlying cirrhosis

Personalised radiation therapy taking both the tumour and patient into consideration

A look through almost 2000 abstracts submitted for the upcoming ESTRO 2022 meeting together with a glance back on the 2021 papers published in Radiotherapy and Oncology gives one a good impression of the (current) key focus areas in radiation oncology: Almost all of this work relates to optimal delivery of radiation therapy in terms of technology, quality assurance and morbidity reducing approaches. Thus, at present the research questions considered as most relevant for radiotherapy of e.g. lung and oesophageal cancer are not related to tumour control, but to the late risk of cardiac disease in the patients who are lucky to survive their cancer long enough to develop such problems [[1]]. The same scenario is found in the patient cohort that constitutes the largest indication for radiotherapy in Europe: women with early breast cancer [[2]]. In these examples, and in many other situations where radiotherapy is applied with a curative intent, less focus has currently been given to the aim or indication of the treatment, namely the control of loco-regional malignant disease. Of course, since Holthusen’s seminal paper in 1936 [[3]] the overall aim of radiotherapy, as stated over and over again by all teachers in the field (including the authors of this editorial), is uncomplicated tumour control, i.e. loco-regional tumour control without severe normal tissue damage (therapeutic ratio). This implies that rigorous study of the effects of radiotherapy on normal, non-tumour, tissues is an absolute necessity. Yet, the prescription of radiotherapy in clinical practice is done to kill tumour cells for local and loco-regional control. If the effects of radiotherapy on tumours are shifting out of focus, it might be taken for granted that the indication, dose, fractionation, and potential multidisciplinary interactions in this field are fully understood, and what remains is the fine tuning of the associated risk of morbidity