Interobserver variation in target volume for salvage radiotherapy in recurrent prostate cancer patients after radical prostatectomy using CT versus combined CT and MRI: a multicenter study (KROG 13-11)
- Author:
Eonju LEE
1
;
Won PARK
;
Sung Hwan AHN
;
Jae Ho CHO
;
Jin Hee KIM
;
Kwan Ho CHO
;
Young Min CHOI
;
Jae Sung KIM
;
Jin Ho KIM
;
Hong Seok JANG
;
Young Seok KIM
;
Taek Keun NAM
Author Information
- Publication Type:Multicenter Study
- Keywords: Prostate cancer; Salvage radiotherapy; Target volume; Interobserver variation; Magnetic resonance image
- MeSH: Humans; Magnetic Resonance Imaging; Observer Variation; Prostate; Prostatectomy; Prostatic Neoplasms; Radiotherapy; Tomography, X-Ray Computed
- From:Radiation Oncology Journal 2018;36(1):11-16
- CountryRepublic of Korea
- Language:English
- Abstract: PURPOSE: To investigate interobserver variation in target volume delineations for prostate cancer salvage radiotherapy using planning computed tomography (CT) versus combined planning CT and magnetic resonance imaging (MRI). MATERIALS AND METHODS: Ten radiation oncologists independently delineated a target volume on the planning CT scans of five cases with different pathological status after radical prostatectomy. Two weeks later, this was repeated with the addition of planning MRI. The volumes obtained with CT only and combined CT and MRI were compared, and the effect of the addition of planning MRI on interobserver variability was assessed. RESULTS: There were large differences in clinical target volume (CTV) delineated by each observer, regardless of the addition of planning MRI (9.44–139.27 cm³ in CT only and 7.77–122.83 cm³ in CT plus MRI) and no significant differences in the mean and standard deviation of CTV. However, there were decreases in mean volume and standard deviation as a result of using the planning MRI. CONCLUSION: This study showed substantial interobserver variation in target volume delineation for salvage radiotherapy. The combination of planning MRI with CT tended to decrease the target volume and the variation.
