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Introduction: The delineation of organs-at-risk and lymph node areas is a crucial step in radiotherapy, but it is time-consuming and associated with substantial user-dependent variability in contouring. Artificial intelligence (AI) appears to be the solution to facilitate and standardize this work. The objective of this study is to compare eight available AI software programs in terms of technical aspects and accuracy for contouring organs-at-risk and lymph node areas with current international contouring recommendations., Material and Methods: From January-July 2023, we performed a blinded study of the contour scoring of the organs-at-risk and lymph node areas by eight self-contouring AI programs by 20 radiation oncologists. It was a single-center study conducted in radiation department at the Lorraine Cancer Institute. A qualitative analysis of technical characteristics of the different AI programs was also performed. Three adults (two women and one man) and three children (one girl and two boys) provided six whole-body anonymized CT scans, along with two other adult brain MRI scans. Using a scoring scale from 1 to 3 (best score), radiation oncologists blindly assessed the quality of contouring of organs-at-risk and lymph node areas of all scans and MRI data by the eight AI programs. We have chosen to define the threshold of an average score equal to or greater than 2 to characterize a high-performing AI software, meaning an AI with minimal to moderate corrections but usable in clinical routine., Results: For adults CT scans: There were two AI programs for which the overall average quality score (that is, all areas tested for OARs and lymph nodes) was higher than 2.0: Limbus (overall average score = 2.03 (0.16)) and MVision (overall average score = 2.13 (0.19)). If we only consider OARs for adults, only Limbus, Therapanacea, MVision and Radformation have an average score above 2. For children CT scan, MVision was the only program to have a average score higher than 2 with overall average score = 2.07 (0.19). If we only consider OARs for children, only Limbus and MVision have an average score above 2. For brain MRIs: TheraPanacea was the only program with an average score over 2, for both brain delineation (2.75 (0.35)) and OARs (2.09 (0.19)). The comparative analysis of the technical aspects highlights the similarities and differences between the software. There is no difference in between senior radiation oncologist and residents for OARs contouring., Conclusion: For adult CT-scan, two AI programs on the market, MVision and Limbus, delineate most OARs and lymph nodes areas that are useful in clinical routine. For children CT-scan, only one IA, MVision, program is efficient. For adult brain MRI, Therapancea,only one AI program is efficient., Trial Registration: CNIL-MR0004 Number HDH434., Competing Interests: Declarations. Ethics approval and consent to participate: This study was approved by ethics and conducted in accordance with the ethical standards of the Declaration of Helsinki (as revised in 2013). This study was approved by Ethics committee named the French National Commission of Informatics and Liberty (CNIL) (CNIL-MR0004 Number HDH434). The present study has been approved by the French Health Data Institute (Health DataHub) as the number HDH301. All methods were carried out in accordance with relevant guidelines and regulations. All participants have signed informed consent to the use of their data for research purposes. Consent for publication: Not applicable. Competing interests: The authors have declared no conflicts of interest. The Lorraine Cancer Institute used MVision AI software until January 1, 2023., (© 2024. The Author(s).)

Patients with bone metastasis are prevalent among those receiving palliative radiotherapy (RT), with approximately 20 % requiring reirradiation (reirradiation). The goal of bone reirradiation may be local control (oligoreoccurrence or oligoprogression of a previously treated lesion or in a previous treatment field) or symptomatic (threatening or painful progression). Published data on bone reirradiation indicate almost two-thirds of overall pain response. The primary organ at risk (especially for spine treatment) is the spinal cord. The risk of radiation myelitis is<1 % for cumulative doses of<50Gy. Intensity-modulated RT (IMRT) and stereotactic RT (SRT) appear to be safer than three-dimensional RT (3DRT), although randomized trials comparing these techniques in reirradiation are lacking. Reirradiation requires multidisciplinary assessment. Alternative treatments for bone metastases (surgery, interventional radiology, etc.) must be considered. Patients should have a performance status≤2, with at least a 1-month interval between treatments. The planning process involves reviewing previous RT plans, cautious dose adjustments, and precise target delineation and dose distribution to minimize toxicity. Cumulative dosimetry, patient consent, and vigilant post-treatment monitoring and dose reporting are crucial., (Copyright © 2024. Published by Elsevier Masson SAS.)

Purpose: To identify dosimetric predictive factors of sensorineural hearing loss (SNHL) in children after cranial radiation therapy (RT) in a single institution using dosimetric data from the French National Registry PediaRT., Methods and Materials: Complete audiological follow-up data were available for 44 children treated with cranial RT between 2014 and 2021 at our institution. The median age at the time of RT initiation was 9 years (range: 2-17 years). No children presented with hearing loss prior to treatment. SNHL was defined as a Chang ototoxicity grade ≥ 1a or higher., Results: Median audiometric follow-up duration was 51 months. Seven children (16 %) developed SNHL with a median time to occurrence of 33 months (range, 18-46 months). The estimated SNHL cumulative rate at 2 years post-RT was 4,5% ± 3,1% and at 5 years was 21 % ± 7.2 %. Multiple Cox regression models showed that the association of the age at radiotherapy and the dosimetric values to the inner ear canal and cochlea were the most significant predictive factors of SNHL occurrence. No child who received less than 35 Gy on average to both cochleae (n = 26) suffered from SNHL, whereas the 5-year SNHL cumulative incidence for the children who received greater than or equal to 35 Gy on average to either cochlea (n = 18) was 51.8 % ± 15.1 %., Conclusion: Doses received by the inner ear canal and cochlea, associated with the age at RT initiation, are the main predictive factors for radiation-induced SNHL. A median dose to either cochlea over 35 Gy significantly increases the risk of SNHL and justify close audiometric monitoring to detect and equip hearing loss at an early stage., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

Purpose: Brachytherapy (BT) is a validated radiation technique for treatment of early stage tumors of oral cavity and oropharynx. This study aimed to analyze the results of our institute's patients after replacing low-dose-rate (LDR) with pulse-dose-rate (PDR) brachytherapy., Material and Methods: We retrospectively collected data from all patients treated between 2009 and 2020 for squamous cell carcinoma (floor of the mouth, tongue, and oropharynx) using adjuvant interstitial BT with or without external RT. Primary outcome was local control. Secondary outcomes were regional control rate and toxicity. Statistical analysis of local and regional recurrences were described using Kaplan-Meier method. Prognostic value of each factor for recurrence or toxicity was evaluated with bivariate Fine-Gray model., Results: Data from 66 patients were analyzed. Local and regional recurrences were reported in 11% and 20% of the patients, respectively. No significant factors were identified in the present study. Grade 2 and 3 acute mucositis were reported in 21% of patients, and were more frequent in the BT only group. Almost half (47%) of the patients described acute pain following BT, and 26% required stage 2 or 3 analgesics. Trophic disorders were observed in 16 patients. Five patients presented with soft tissue necrosis (STN) and required medical treatment, of whom one subsequently required hyperbaric oxygen therapy. No predictive factors were identified for STN risk. Two patients developed osteoradionecrosis., Conclusions: Oral and oropharyngeal PDR-BT as adjuvant treatment is safe and effective for well-defined indications., Competing Interests: The authors report no conflict of interest., (Copyright © 2023 Termedia.)

Purpose: To identify dosimetric predictive factors of facial nerve paralysis for patients with vestibular schwannomas (VS) treated in a single institution with Cyberknife® (CK) hypofractionated stereotactic radiotherapy (SRT)., Methods and Materials: Eighty-eight patients were treated from 2010 to 2020. Different treatment schedules were used over that period, some prescribed to the 80% isodose line (4 × 5 Gy, 3 × 7 Gy, 3 × 8 Gy and 5 × 5 Gy) and one to the 70% isodose line (3 × 7.7 Gy). Local control tumor and facial nerve toxicity were recorded, as well as various dosimetric indicators., Results: Median follow-up 37 months (range, 7-96). Of the 88 stereotactic treatments, 20 patients (23%) developed objectively diagnosed radiation-induced facial nerve paralysis. The 2-year and 5-year local tumor control were respectively 95% and 88%, and the overall 2-year facial nerve preservation was 76%. Prescriptions with a maximum dose point (Dmax) of 33 Gy were at a substantially higher risk of facial paralysis than prescriptions with a Dmax less than or equal to 30 Gy (HR = 4.51, 95% CI = [1.04;19.6], p = 0.045). The 2-years cumulative incidences of facial paralysis were 32% [20%;44%] in the case of a 33 Gy Dmax, against 7% [1%;21%] otherwise. We identified four significative dosimetric predictive factors for radiation-induced facial nerve dysfunction: a GTV minimal dose over 22 Gy (EQD2 = 45.5 Gy, p = 0.019), a GTV mean dose over 29 Gy (EQD2 = 73.5 Gy, HR = 2.84, 95% CI = [1.10;7.36], p = 0.024), a PTV mean dose over 27 Gy (EQD2 = 64.8 Gy, HR = 10.52, 95% CI = [1.39;79.76], p = 0.002) and a PTV maximal dose of 32 Gy (EQD2 = 87.5 Gy,HR = 5.09, 95% CI = [1.17;22.15], p = 0.013)., Conclusion: We identified four dosimetric predictive factors for post-treatment facial paralysis. Increasing the doses of hypofractionated stereotactic radiotherapy for vestibular schwannomas leads to higher facial nerve toxicity and may lead to lower local control rates than other published series. Our three-hypofractionated regimens may have also played a role in these results., (Copyright © 2023 Elsevier B.V. All rights reserved.)