98%
921
2 minutes
20
Purpose/objective: The Danish Breast Cancer Group (DBCG) IMN2 study investigated the gain from internal mammary node irradiation (IMNI) in node-positive breast cancer patients. IMNI was indicated in right-sided patients, but not in left-sided. Target volume delineations were based on bony landmarks in contrast to the contemporary vessel-based ESTRO consensus guideline. Our objective was to compare IMNI doses in right-sided versus left-sided patients.
Material/methods: Treatment plans and delineated structures including CTVn_IMN (IMN_old) from 2008 to 2014 were collected from the DBCG RT Nation study. During the study period, IMN_old was only delineated in right-sided patients. Right and left-sided CTVn_IMN structures were auto-segmented following the ESTRO guidelines (IMN_ESTRO). Due to cranial discordance between IMN_old and IMN_ESTRO, the IMN_ESTRO models were separated into IMN_ESTRO_cranial and IMN_ESTRO_intercostal space(IC)1-3, IC1-4, and IC4_only.
Results: Treatment plans for 2837 patients were available (62.5 % of patients in the IMN2 study). In right-sided patients, the median IMN_old dose coverage (92.4 %) was higher than IMN_ESTRO (71.7 %), p < 0.001. Dose coverage in IMN_ESTRO_IC1-3 was comparable to IMN_old. Comparing IMN_ESTRO_IC1-3 in all patients by laterality, the median CTVn_V90% was 94.6 % (IQR 64.8-100.0) in right-sided patients and 20.4 % (IQR 0.9-55.8) in left-sided patients, p < 0.001. For right-sided patients, median CTV_V90% was 82.3 % in IMN_ESTRO_IC4_only. Median mean heart doses were lower in right-sided patients (1.2 Gy) than in left-sided (2.3 Gy), p < 0.001. Median mean lung doses were higher in right-sided patients (16.0 Gy) than in left-sided (12.7 Gy), p < 0.001.
Conclusion: For IMN_ESTRO_IC1-3, we found a significantly higher IMN dose coverage in right-sided than in left-sided patients supporting treatment according to study guidelines in the DBCG IMN2 study.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.radonc.2024.110600 | DOI Listing |
Breast
June 2025
Department of Pathology, Aarhus University Hospital, Aarhus, Denmark; Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.
Introduction: Radiotherapy significantly reduces locoregional recurrence (LRR) and improves survival. Yet, reliable biomarkers predicting radiotherapy response are not well-defined. Tumor-infiltrating lymphocytes (TILs) have emerged as a promising prognostic and predictive marker, but their role in irradiated patients remains underexplored.
View Article and Find Full Text PDFRadiother Oncol
June 2025
Department of Experimental Clinical Oncology, Aarhus University Hospital, Aarhus, Denmark; Department of Clinical Medicine, Aarhus University, Aarhus, Denmark; Department of Oncology, Aarhus University Hospital, Aarhus Denmark; Danish Center for Particle Therapy, Aarhus University Hospital, Aarhus D
Background And Purpose: In early-stage breast cancer, a tumour-bed boost (TBB) reduces the risk of local recurrence (LR) by around 50 % but increases the risk of breast induration. LR incidences of 3 % at 5 years and 6 % at 10 years have been proposed as thresholds where benefits outweigh the potentially detrimental effects of a TBB. Therefore, this post-hoc analysis of the Danish Breast Cancer Group (DBCG) IMN2 study aimed to investigate LR rates according to prognostic risk factors to identify indications for a TBB.
View Article and Find Full Text PDFLancet Reg Health Eur
February 2025
Department of Experimental Clinical Oncology, Aarhus University Hospital, Aarhus, Denmark.
Background: Internal mammary node irradiation (IMNI) improves overall survival (OS) in node-positive breast cancer patients. However, the effect is not documented in breast cancer patients treated with newer systemic therapies and 3D-based radiotherapy (RT). Therefore, the Danish Breast Cancer Group (DBCG) IMN2 study aimed to investigate the effect of IMNI in node-positive breast cancer patients treated with newer systemic therapies and 3D-based RT.
View Article and Find Full Text PDFRadiother Oncol
January 2025
Danish Center for Particle Therapy, Aarhus University Hospital, Aarhus, Denmark; Department of Clinical Medicine, Aarhus University, Aarhus, Denmark; Department of Experimental Clinical Oncology, Aarhus University Hospital, Aarhus, Denmark; Department of Oncology, Aarhus University Hospital, Aarhus,
Purpose/objective: The Danish Breast Cancer Group (DBCG) IMN2 study investigated the gain from internal mammary node irradiation (IMNI) in node-positive breast cancer patients. IMNI was indicated in right-sided patients, but not in left-sided. Target volume delineations were based on bony landmarks in contrast to the contemporary vessel-based ESTRO consensus guideline.
View Article and Find Full Text PDF