Emma M Dunne1, Arjun Sahgal2, Simon S Lo3, Alanah Bergman4, Robert Kosztyla4, Nicolas Dea5, Eric L Chang6, Ung-Kyu Chang7, Samuel T Chao8, Salman Faruqi9, Amol J Ghia10, Kristin J Redmond11, Scott G Soltys12, Mitchell C Liu4. 1. Department of Radiation Oncology, BC Cancer - Vancouver Centre, Canada. Electronic address: emmamaria.dunne@gmail.com. 2. Department of Radiation Oncology, Odette Cancer Centre, Sunnybrook Health Sciences Centre, University of Toronto, Canada. 3. University of Washington, Department of Radiation Oncology, Seattle, USA. 4. Department of Radiation Oncology, BC Cancer - Vancouver Centre, Canada. 5. Vancouver Spine Surgery Institute, Division of Neurosurgery, Department of Surgery, University of British Columbia, Vancouver General Hospital, Canada. 6. University of Southern California Keck School of Medicine, Los Angeles, USA. 7. Department of Neurosurgery, Korea Institute of Radiological & Medical Sciences, Seoul, South Korea. 8. Department of Radiation Oncology, Taussig Cancer Center, Cleveland Clinic, USA. 9. Department of Radiation Oncology, Tom Baker Cancer Centre, University of Calgary, Canada. 10. Dept. of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, USA. 11. Johns Hopkins University School of Medicine, Baltimore, USA. 12. Department of Radiation Oncology, Stanford Cancer Institute, USA.
Abstract
BACKGROUND AND PURPOSE: To interrogate inter-observer variability in gross tumour volume (GTV) and clinical target volume (CTV) delineation specific to the treatment of sacral metastases with spinal stereotactic body radiation therapy (SBRT) and develop CTV consensus contouring recommendations. MATERIALS AND METHODS: Nine specialists with spinal SBRT expertise representing 9 international centres independently contoured the GTV and CTV for 10 clinical cases of metastatic disease within the sacrum. Agreement between physicians was calculated with an expectation minimisation algorithm using simultaneous truth and performance level estimation (STAPLE) and with kappa statistics. Optimised confidence level consensus contours were obtained using a voxel-wise maximum likelihood approach and the STAPLE contours for GTV and CTV were based on an 80% confidence level. RESULTS: Mean GTV STAPLE agreement sensitivity and specificity was 0.70 (range, 0.54-0.87) and 1.00, respectively, and 0.55 (range, 0.44-0.64) and 1.00 for the CTV, respectively. Mean GTV and CTV kappa agreement was 0.73 (range, 0.59-0.83) and 0.59 (range, 0.41-0.70), respectively. Optimised confidence level consensus contours were identified by STAPLE analysis. Consensus recommendations for the CTV include treating the entire segment containing the disease in addition to the immediate adjacent bony anatomic segment at risk of microscopic extension. CONCLUSION: Consensus recommendations for CTV target delineation specific to sacral metastases treated with SBRT were established using expert contours. This is a critical first step to achieving standardisation of target delineation practice in the sacrum and will serve as a baseline for meaningful pattern of failure analyses going forward.
BACKGROUND AND PURPOSE: To interrogate inter-observer variability in gross tumour volume (GTV) and clinical target volume (CTV) delineation specific to the treatment of sacral metastases with spinal stereotactic body radiation therapy (SBRT) and develop CTV consensus contouring recommendations. MATERIALS AND METHODS: Nine specialists with spinal SBRT expertise representing 9 international centres independently contoured the GTV and CTV for 10 clinical cases of metastatic disease within the sacrum. Agreement between physicians was calculated with an expectation minimisation algorithm using simultaneous truth and performance level estimation (STAPLE) and with kappa statistics. Optimised confidence level consensus contours were obtained using a voxel-wise maximum likelihood approach and the STAPLE contours for GTV and CTV were based on an 80% confidence level. RESULTS: Mean GTV STAPLE agreement sensitivity and specificity was 0.70 (range, 0.54-0.87) and 1.00, respectively, and 0.55 (range, 0.44-0.64) and 1.00 for the CTV, respectively. Mean GTV and CTV kappa agreement was 0.73 (range, 0.59-0.83) and 0.59 (range, 0.41-0.70), respectively. Optimised confidence level consensus contours were identified by STAPLE analysis. Consensus recommendations for the CTV include treating the entire segment containing the disease in addition to the immediate adjacent bony anatomic segment at risk of microscopic extension. CONCLUSION: Consensus recommendations for CTV target delineation specific to sacral metastases treated with SBRT were established using expert contours. This is a critical first step to achieving standardisation of target delineation practice in the sacrum and will serve as a baseline for meaningful pattern of failure analyses going forward.
Authors: Roman O Kowalchuk; Michael R Waters; K Martin Richardson; Kelly Spencer; James M Larner; Jason P Sheehan; William H McAllister; Charles R Kersh Journal: J Radiosurg SBRT Date: 2020
Authors: Liam S P Lawrence; Lee C L Chin; Rachel W Chan; Timothy K Nguyen; Arjun Sahgal; Chia-Lin Tseng; Angus Z Lau Journal: Radiat Oncol Date: 2021-04-13 Impact factor: 3.481
Authors: F Vilotte; D Pasquier; P Blanchard; S Supiot; J Khalifa; U Schick; T Lacornerie; L Vieillevigne; D Marre; O Chapet; I Latorzeff; N Magne; E Meyer; K Cao; Y Belkacemi; J E Bibault; M Berge-Lefranc; J C Faivre; K Gnep; V Guimas; A Hasbini; J Langrand-Escure; C Hennequin; P Graff Journal: Clin Transl Radiat Oncol Date: 2022-08-08