Comparison of interobserver variations in delineation of target volumes and organs-at-risk for intensity-modulated radiotherapy of nasopharyngeal carcinoma among physicians from different levels of cancer centers(PDF)
《中国医学物理学杂志》[ISSN:1005-202X/CN:44-1351/R]
- Issue:
- 2024年第3期
- Page:
- 265-272
- Research Field:
- 医学放射物理
- Publishing date:
Info
- Title:
- Comparison of interobserver variations in delineation of target volumes and organs-at-risk for intensity-modulated radiotherapy of nasopharyngeal carcinoma among physicians from different levels of cancer centers
- Author(s):
- CHEN Meining1; 2; LIU Yimei2; PENG Yinglin2; XIE Qiuying3; SHI Jinping3; HUANG Rong3; ZHAO Chong2; DENG Xiaowu2; ZHOU Meijuan1
- 1. Department of Radiology, School of Public Health, Southern Medical University/Key Laboratory of Cosmetics Safety Evaluation, National Medical Products Administration/Key Laboratory of Tropical Diseases Research, Guangzhou 510515, China 2. Sun Yat-sen University Cancer Center/State Key Laboratory of Oncology in South China/Key Laboratory of Diagnosis and Treatment of Nasopharyngeal Cancer in Guangdong Province, Guangzhou 510060, China 3. Department of Radiation Oncology, the First Peoples Hospital of Foshan, Foshan 528010, China
- Keywords:
- Keywords: nasopharyngeal carcinoma intensity modulated radiotherapy organ segmentation absolute volume difference ratio Dice similarity coefficient coefficient of variation
- PACS:
- R739.62
- DOI:
- DOI:10.3969/j.issn.1005-202X.2024.03.001
- Abstract:
- Abstract: Objective To assess inter-observer variations (IOV) in the delineation of target volumes and organs-at-risk (OAR) for intensity-modulated radiotherapy (IMRT) of nasopharyngeal carcinoma (NPC) among physicians from different levels of cancer centers, thereby providing a reference for quality control in multi-center clinical trials. Methods Twelve patients with NPC of different TMN stages were randomly selected. Three physicians from the same municipal cancer center manually delineated the target volume (GTVnx) and OAR for each patient. The manually modified and confirmed target volume (GTVnx) and OAR delineation structures by radiotherapy experts from the regional cancer center were used as the standard delineation. The absolute volume difference ratio (△V_diff), maximum/minimum volume ratio (MMR), coefficient of variation (CV), and Dice similarity coefficient (DSC) were used to compare the differences in organ delineation among physicians from different levels of cancer centers and among the 3 physicians from the same municipal cancer center. Furthermore, the IOV of GTVnx and OAR among physicians from different levels cancer centers were compared across different TMN stages. Results Significant differences in the delineation of GTVnx were observed among physicians from different levels of cancer centers. Among the 3 physicians, the maximum values of △V_diff, MMR, and CV were 97.23%±83.45%, 2.19±0.75, and 0.31±0.14, respectively, with an average DSC of less than 0.7. Additionally, there were considerable differences in the delineation of small-volume OAR such as the left and right optic nerves, chiasm, and pituitary, with average MMR>2.8, CV>0.37, and DSC<0.51. However, relatively smaller differences were observed in the delineation of large-volume OAR such as the brainstem, spinal cord, left and right eyeballs, and left and right mandible, with average △V_diff<42%, MMR<1.55, and DSC>0.7. Compared with the differences among physicians from different levels cancer centers, the differences among the 3 physicians from the municipal cancer center were slightly reduced. Furthermore, there were also differences in the delineation of target volumes for NPC among physicians from different levels cancer centers, depending on the staging of the disease. Compared with the delineation of target volumes for earlier stage patients (stages I or II), the differences among physicians in the delineation of target volumes for advanced stage patients (stages III or IV) were smaller, with average △V_diff and DSC of 98.31%±67.36% vs 69.38%±72.61% (P<0.05) and 0.55±0.08 vs 0.72±0.12 (P<0.05), respectively. Conclusion There are differences in the delineation of GTVnx and OAR in radiation therapy for NPC among physicians from different levels of cancer centers, especially in the delineation of target volume (GTVnx) and small-volume OAR for early-stage patients. To ensure the accuracy of multicenter clinical trials, it is recommended to provide unified training to physicians from different levels of cancer centers and review their delineation results to reduce the effect of differences on treatment outcomes.
Last Update: 2024-04-08