Impact of excluding internal mammary node coverage on musculoskeletal dosimetry in breast radiotherapy
Notice bibliographique
Résumé
Purpose: Breast cancer radiotherapy (RT) can lead to shoulder complications including weakness, restricted motion, and discomfort, affecting up to 40% of patients. The necessity to include the internal mammary nodes (IMNs) during breast and nodal irradiation for every patient remains under discussion, particularly for early-stage breast cancers. The dosimetric effect on nearby musculoskeletal (MSK) structures when targeting the IMNs remains to be completely understood; hence the focus of this current study. Methods: This retrospective study included breast cancer patients who underwent lumpectomy and nodal sampling followed by adjuvant hypofractionated whole breast and regional nodal RT (4005 cGy in 15 fractions) who were treated between January 1, 2022, and November 30, 2023 at a single institution. MSK structures such as the bones (ribs, scapula), muscles (pectoralis, rhomboids), and joints (glenohumeral, acromioclavicular) were retrospectively contoured on the CT simulation images. Two RT plans (one with and one without IMN coverage) were created, and dosimetric parameters including mean (Dmean), near maximum (D2), near minimum (D98) and volumes received 15, 20 and 40 Gy (V15, V20, V40) were compared. Standardized mean difference between the plans was calculated for each dosimetric parameter, and Wilxocon's signed-rank test was used for comparison. Univariable linear regression analysis was used to identify patient and tumor factors that were associated with more significant dosimetric differences. Results: A total of 30 breast cancer patients with a median age of 63 (range 30-82 years) were selected for analysis. The location of tumours included 15 (50 %) in the right breast, and 15 (50 %) in the left breast; with 10 (33 %) centrally, 10 (33 %) medially, and 10 (33 %) were laterally-located within the breast. The pathologic T stage included 6 (20 %) T0/Tis, 11 (37 %) T1, and 13 (43 %) T2. Seven patients (23 %) were N0, 19 (63 %) were N1, and 4 (13 %) were N2a. Nine patients received adjuvant chemotherapy, 11 neoadjuvant chemotherapy, and 10 patients received no chemotherapy.The exclusion of IMN coverage led to significantly decreased Dmean for muscle groups in the posterior, posterolateral, lateral, anterior and antero-lateral-posterior regions. Specifically, the largest absolute reductions included teres major (Dmean 340 cGy), subscapularis (320 cGy), serratus anterior (241 cGy), latissimus dorsi (232 cGy), chestwall (209 cGy), and the pectoralis minor (37 cGy) muscles. Significant differences were also observed for V40 and V15 of pectoralis minor (V40 of 12 %), pectoralis major (V40 of 10 %), and for both subscapularis and teres major (V15 of 8 %) muscles.Patient factors that were associated with greater dosimetric differences included younger age, larger breast size, larger tumor cavity, and non-central tumor locations. Conclusion: dosmetric analysis clearly demonstrated that excluding IMN coverage for breast RT significantly reduced the dose received by the MSK structures of the neck, chest wall, and shoulder, particularly in the posterior muscle groups. Future research with larger cohorts and prospective designs would be required to validate these dosimetric benefits and their relationship to MSK-related side effects post-radiotherapy.
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 | 0,002 | 0,005 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,000 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,001 | 0,000 |
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 ».