Quantitative assessment of inter-observer consistency in target volume delineation following breast-conserving surgery and mastectomy.
Contouring agreement among oncologists is poor for axillary Level III lymph node volumes
Quantitative assessment of inter-observer consistency in target volume delineation following breast-conserving surgery and mastectomy.
Consistent clinical target volume (clinical target volume) delineation is vital for breast cancer radiotherapy.
To quantify inter-observer discrepancies in postoperative breast cancer clinical target volume contouring among regional oncologists and to qualitatively analyze the reasons for these contouring discrepancies to promote standardization and quality assurance.
Based on CT datasets of two representative post-surgical breast cancer cases (BCS and MRM), 22 frontline radiation oncologists from regional municipal hospitals independently contoured the required CTVs.
A total of 20 completed datasets, each for both the BCS and MRM cases, were successfully retrieved and analyzed.
The large volumes achieved the highest overlap ( CTVp_breast and CTVp_thoracic wall dice similarity coefficients mean: 0.80 ± 0.07 and 0.63 ± 0.08, respectively), though mean 95% Hausdorff distances (hausdorff distances 95 ) were elevated at 42.84 ± 50.62 mm and 45.73 ± 60.44 mm.
Delineation consistency is acceptable for large volumes ( CTVp_breast and CTVp_thoracic wall ) but poor for regional nodal stations, demonstrating that standardized anatomical training is crucial to improve radiotherapy uniformity.