Apport de l'IRM dans la délinéation de la prostate en radiothérapie

Dans le traitement du cancer de la prostate, l'escalade de dose augmente la survie sans récidive biologique. La radiothèrapie conformationnelle avec modulation d'intensité (RCMI) permet de mieux sculpter la dose au volume cible. Les appareils de traitement possédant une imagerie 3D embarquée assurent un repositionnement précis. La délinéation de la prostate par le radiothèrapeute doit donc être la plus juste possible. Sur dix patients traités pour un adénocarcinome de la prostate, nous avons comparé les contours réalisés avec puis sans recalage de l'image remnographique par plusieurs médecins. Le recalage ainsi effectué d'image permet de diminuer les variations de contours entre différents médecins, de mieux situer l'apex prostatique, de diminuer le volume cible prostatique et de diminuer la dose reçue par le rectum. Il est important d'intégrer cette technique dans l'ensemble des moyens modernes de traitement en radiothérapie.LIMOGES-BU Médecine pharmacie (870852108) / SudocSudocFranceF

Weekly Adaptive Radiotherapy vs Standard Intensity-Modulated Radiotherapy for Improving Salivary Function in Patients With Head and Neck Cancer

International audienceImportance: Xerostomia is a major toxic effect associated with intensity-modulated radiotherapy (IMRT) for oropharyngeal cancers.Objective: To assess whether adaptive radiotherapy (ART) improves salivary function compared with IMRT in patients with head and neck cancer.Design, setting, and participants: This phase 3 randomized clinical trial was conducted in 11 French centers. Patients aged 18 to 75 years with stage III-IVB squamous cell oropharyngeal cancer treated with chemoradiotherapy were enrolled between July 5, 2013, and October 1, 2018. Data were analyzed from November 2021 to May 2022.Interventions: The patients were randomly assigned (1:1) to receive standard IMRT (without replanning) or ART (systematic weekly replanning).Main outcomes and measures: The primary end point was the frequency of xerostomia, measured by stimulating salivary flow with paraffin. Secondary end points included salivary gland excretory function measured using technetium-99m pertechnetate scintigraphy, patient-reported outcomes (Eisbruch xerostomia-specific questionnaire and the MD Anderson Symptom Inventory for Head and Neck Cancer questionnaire), early and late toxic effects, disease control, and overall and cancer-specific survival.Results: A total of 132 patients were randomized, and after 1 exclusion in the ART arm, 131 were analyzed: 66 in the ART arm (mean [SD] age at inclusion, 60 [8] years; 57 [86.4%] male) and 65 in the standard IMRT arm (mean [SD] age at inclusion, 60 [8] years; 57 [87.7%] male). The median follow-up was 26.4 months (IQR, 1.2-31.3 months). The mean (SD) salivary flow (paraffin) at 12 months was 630 (450) mg/min in the ART arm and 584 (464) mg/min in the standard arm (P = .64). The mean (SD) excretory function of the parotid gland at 12 months, measured by scintigraphy, improved in the ART arm (48% [17%]) compared with the standard arm (41% [17%]) (P = .02). The 2-year-overall survival was 76.9% (95% CI, 64.7%-85.4%) in both arms.Conclusions and relevance: This randomized clinical trial did not demonstrate a benefit of ART in decreasing xerostomia compared with standard IMRT. No significant differences were found in secondary end points except for parotid gland excretory function, as assessed by scintigraphy, or in survival rates.Trial registration: ClinicalTrials.gov Identifier: NCT01874587

Cost-effectiveness of weekly adaptive radiotherapy versus standard IMRT in head and neck cancer alongside the ARTIX trial

International audienceBACKGROUND AND PURPOSE: We performed a cost-effectiveness analysis (CEA) comparing an adaptive radiotherapy (ART) strategy, based on weekly replanning, aiming to correct the parotid gland overdose during treatment and expecting therefore to decrease xerostomia, when compared to a standard IMRT. MATERIALS AND METHODS: We conducted the ARTIX trial, a randomized, parallel-group, multicentric study comparing a systematic weekly replanning ART to a standard IMRT. The primary endpoint was the frequency of xerostomia at 12 months, measured by stimulating salivary flow with paraffin. The CEA was designed alongside the ARTIX trial which was linked to the French national health data system (SNDS). For each patient, healthcare consumptions and costs were provided by the SNDS. The reference case analysis was based on the primary endpoint of the trial. Sensitivity and scenario analyses were performed. RESULTS: Of the 129 patients randomly assigned between 2013 and 2018, only 2 records were not linked to the SNDS, which provides a linkage proportion of 98.4%. All of the other 127 records were linked with good to very good robustness. On the intent-to-treat population at 12 months, mean total costs per patient were €41,564 (SD 23,624) and €33,063 (SD 16,886) for ART and standard IMRT arms, respectively (p = 0.033). Incremental cost effectiveness ratio (ICER) was €162,444 per xerostomia avoided. At 24 months, ICER was €194,521 per xerostomia avoided. For both progression-free and overall survival, ART was dominated by standard IMRT. CONCLUSION: The ART strategy was deemed to be not cost-effective compared with standard IMRT for patients with locally advanced oropharyngeal cancer