Dataset Information

Interobserver variability in target volume delineation in definitive radiotherapy for thoracic esophageal cancer: a multi-center study from China.

ABSTRACT:

Purpose

To investigate the interobserver variability (IOV) in target volume delineation of definitive radiotherapy for thoracic esophageal cancer (TEC) among cancer centers in China, and ultimately improve contouring consistency as much as possible to lay the foundation for multi-center prospective studies.

Methods

Sixteen cancer centers throughout China participated in this study. In Phase 1, three suitable cases with upper, middle, and lower TEC were chosen, and participants were asked to contour a group of gross tumor volume (GTV-T), nodal gross tumor volume (GTV-N) and clinical target volume (CTV) for each case based on their routine experience. In Phase 2, the same clinicians were instructed to follow a contouring protocol to re-contour another group of target volume. The variation of the target volume was analyzed and quantified using dice similarity coefficient (DSC).

Results

Sixteen clinicians provided routine volumes, whereas ten provided both routine and protocol volumes for each case. The IOV of routine GTV-N was the most striking in all cases, with the smallest DSC of 0.37 (95% CI 0.32-0.42), followed by CTV, whereas GTV-T showed high consistency. After following the protocol, the smallest DSC of GTV-N was improved to 0.64 (95% CI 0.45-0.83, P = 0.005) but the DSC of GTV-T and CTV remained constant in most cases.

Conclusion

Variability in target volume delineation was observed, but it could be significantly reduced and controlled using mandatory interventions.

SUBMITTER: Chang X

PROVIDER: S-EPMC8188796 | biostudies-literature | 2021 Jun

REPOSITORIES: biostudies-literature

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Publications

Interobserver variability in target volume delineation in definitive radiotherapy for thoracic esophageal cancer: a multi-center study from China.

Chang Xiao X Deng Wei W Wang Xin X Zhou Zongmei Z Yang Jun J Guo Wenling W Liu Miaoling M Qi Xiaolu X Li Ling L Zhang Kaixian K Zhang Min M Shi Yonggang Y Liu Ke K Zhao Yidian Y Wang Huitao H Yu Zhilong Z Zhang Jihong J Wang Lihua L Qiao Xueying X Han Chun C Zhu Shuchai S Zhang Ruohui R Chen Junqiang J Hu Cairong C Zhang Fuquan F Hou Xiaorong X Pang Qingsong Q Zhang Wencheng W Li Gaofeng G Lin Hailei H Sun Xinchen X Ge Xiaolin X Li Caihong C Ge Hong H Li Dingjie D Wang Yadi Y Lu Na N Gao Xianshu X Qin Shangbin S Tian Yuan Y Xiao Zefen Z

Radiation oncology (London, England) 20210609 1

<h4>Purpose</h4>To investigate the interobserver variability (IOV) in target volume delineation of definitive radiotherapy for thoracic esophageal cancer (TEC) among cancer centers in China, and ultimately improve contouring consistency as much as possible to lay the foundation for multi-center prospective studies.<h4>Methods</h4>Sixteen cancer centers throughout China participated in this study. In Phase 1, three suitable cases with upper, middle, and lower TEC were chosen, and participants wer ...[more]

PMID: 34107984

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Dataset Information

Interobserver variability in target volume delineation in definitive radiotherapy for thoracic esophageal cancer: a multi-center study from China.

Purpose

Methods

Results

Conclusion

Publications

Interobserver variability in target volume delineation in definitive radiotherapy for thoracic esophageal cancer: a multi-center study from China.

Similar Datasets

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