1: The Potential Benefit of Esophageal Sparing During Palliative Radiotherapy for Lung Cancer
Notice bibliographique
Résumé
Purpose: A 2007 meta-analysis of several randomized controlled trials assessing optimal doses for palliative lung radiation concluded that radiation doses of 35 Gy10 or greater improved overall survival at one and two years compared to lower doses at the cost of an increased toxicity related to esophagitis.Esophageal sparing has been proposed as a mechanism of reducing this toxicity.A planning study was initiated to assess the potential impact of esophageal-sparing IMRT (ES-IMRT) for palliative lung radiotherapy, compared to the current standard of care using parallel-opposed pair beams (POP). Methods and Materials:In this institutional research ethics board-approved study, patients with lung cancer treated to a dose of 30 Gy in 10 fractions between August 2015 and January 2016 were identified.Additional inclusion criteria required the D50 to contain at least 5 cm of esophagus.The radiation treatment plans were optimized using ES-IMRT by limiting the max esophageal point dose to 80% of the prescription.This was achieved by creating a 5 mm ring around the esophagus.If any portion of the GTV was within this ring, the coverage was compromised such that a point dose could receive as low as 80% of the intended prescription.Both the clinical POP and optimized ES-IMRT plans were evaluated for the likelihood of esophagitis (≥ Grade 2) and pneumonitis (≥ Grade 2), using published Lyman-Kutcher-Burman normal tissue complication probabilities (LKB-NTCP) models.The input parameters for the LKB models were D50 = 44.9,n = 0.34, m = 0.34 and D50 = 29.9,n = 1, m = 0.41 for esophagitis and pneumonitis, respectively.The mean normalized total dose (NTD mean) of the PTV, and the mean dose to the esophagus (esophageal mean) and lung (lung mean) were determined.Results: A total of 13 patients met our inclusion criteria and were analyzed, of which 11/13 had the GTV directly abutting the esophagus.The median [range] of the GTV and PTV were 90.6 cc [22.3 -199.8] and 321.8 cc [164.1 -564.9],respectively.Using ES-IMRT, the median esophageal mean and lung mean dose reduced from 17.0 and 7.9 Gy to 6.8 and 7.7 Gy, respectively.Using the LKB model, the theoretical probability of symptomatic esophagitis and pneumonitis reduced from 13 to 1%, and from 5 to 3%, respectively.The median clinical POP NTDmean was 32.8 Gy, while the median ES-IMRT NTDmean was 33.2 Gy.Conclusions: Advanced radiotherapy techniques such as ES-IMRT may have clinical utility in reducing treatment-related toxicity in advanced lung cancer patients.Our data suggests that the rate of esophagitis can be reduced from 13 to 1%, without compromising tumour control.The results of this planning study will inform the design of a Phase II randomized controlled trial, Palliative Radiation of Advanced Central lung Tumours with Intentional Avoidance of the Esophagus (PROACTIVE).
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,001 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,001 | 0,001 |
| Bibliométrie | 0,000 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,001 | 0,001 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,001 | 0,001 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,013 | 0,002 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule source (Gemma direct ou Codex distillé), pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».