Zhang YZ, Zhu XG, Song MX, Yao KN, Li S, Geng JH, Wang HZ, Li YH, Cai Y, Wang WH. Improving the accuracy and consistency of clinical target volume delineation for rectal cancer by an education program. World J Gastrointest Oncol 2022; 14(5): 1027-1036 [PMID: 35646284 DOI: 10.4251/wjgo.v14.i5.1027]
Corresponding Author of This Article
Wei-Hu Wang, MD, Chief Physician, Department of Radiation Oncology, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Peking University Cancer Hospital & Institute, No. 52 Fucheng Road, Haidian District, Beijing 100142, China. wangweihu88@163.com
Research Domain of This Article
Oncology
Article-Type of This Article
Retrospective Study
Open-Access Policy of This Article
This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
World J Gastrointest Oncol. May 15, 2022; 14(5): 1027-1036 Published online May 15, 2022. doi: 10.4251/wjgo.v14.i5.1027
Table 1 Definitions and formulas of the indices used for comparison
Indices
Definition
Formula
Indices for geometric comparison analysis
Dice similarity coefficient index
Intersection of Vstu and Vref divided by their average
2 (Vstu ∩ Vref)/(Vstu + Vref)
Inclusiveness index
Intersection of Vstu and Vref divided by Vstu
(Vref ∩ Vstu)/Vstu
Concordance index
Intersection of Vstu and Vref divided by their union
(Vref ∩ Vstu)/(Vref ∪ Vstu)
Relative volume difference
Difference between Vstu and Vref divided by Vref and multiplied by 100
(Vstu-Vref)/Vref × 100
Indices for interobserver variation
Maximum volume ratio
Ratio of the maximum volume to minimum volume contoured by the participants
Vmax/Vmin
Coefficient of variation
Standard deviation of the volumes contoured by the participants multiplied by 100 and divided by the mean value
SD × 100/mean
Table 2 Quantitative analysis of target volume parameters
Indices
Before the education program
After the education program
t/Z value
P value
Volume (cm3)
809.82 ± 141.17 (624.69-1112.79)
705.21 ± 100.53 (603.97-949.53)
-3.180
0.001
Length (cm)
18.19 ± 1.01 (16.50-20.00)
17.77 ± 0.60 (17.00-19.00)
1.442
0.175
DSC
0.78 ± 0.06 (0.68-0.87)
0.84 ± 0.04 (0.71-0.88)
-2.621
0.009
IncI
0.69 ± 0.10 (0.57-0.83)
0.79 ± 0.08 (0.58-0.87)
-3.926
0.002
CI
0.65 ± 0.08 (0.52-0.77)
0.73 ± 0.06 (0.56-0.78)
-2.551
0.011
ΔV (%)
30.79 ± 10.65 (17.33-47.65)
21.43 ± 7.80 (12.93-41.70)
3.926
0.002
Table 3 Quantitative analysis of interobserver variation
Vmax (cm3)
Vmin (cm3)
Mean (cm3)
SD (cm3)
MVR
CV
Before the education program
1112.79
624.69
809.82
141.17
1.78
17.43
After the education program
949.53
603.97
705.21
100.53
1.57
14.26
Decrease ratio
14.67%
3.32%
12.92%
28.79%
11.80%
18.19%
Table 4 Qualitative analysis of target volume variations
Parameters
Before the education program
After the education program
P value
Yes
No
Yes
No
CTV start from the bifurcation of the common iliac artery
8 (61.54%)
5 (38.46%)
12 (92.31%)
1 (7.69%)
0.16
Delineate external iliac area
8 (61.54%)
5 (38.46%)
1 (7.69%)
12 (92.31%)
0.01
Delineate inguinal area
0 (0%)
13 (100%)
0 (0.00%)
13 (100%)
NA
Delineate ischiorectal fossa
7 (53.85%)
6 (46.15%)
1 (7.69%)
12 (92.31%)
0.03
Citation: Zhang YZ, Zhu XG, Song MX, Yao KN, Li S, Geng JH, Wang HZ, Li YH, Cai Y, Wang WH. Improving the accuracy and consistency of clinical target volume delineation for rectal cancer by an education program. World J Gastrointest Oncol 2022; 14(5): 1027-1036