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Le Bao V, Haworth A, Dowling J, Walker A, Arumugam S, Jameson M, Chlap P, Wiltshire K, Keats S, Cloak K, Sidhom M, Kneebone A, Holloway L. Evaluating the relationship between contouring variability and modelled treatment outcome for prostate bed radiotherapy. Phys Med Biol 2024; 69:085008. [PMID: 38471173 DOI: 10.1088/1361-6560/ad3325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2023] [Accepted: 03/12/2024] [Indexed: 03/14/2024]
Abstract
Objectives.Contouring similarity metrics are often used in studies of inter-observer variation and automatic segmentation but do not provide an assessment of clinical impact. This study focused on post-prostatectomy radiotherapy and aimed to (1) identify if there is a relationship between variations in commonly used contouring similarity metrics and resulting dosimetry and (2) identify the variation in clinical target volume (CTV) contouring that significantly impacts dosimetry.Approach.The study retrospectively analysed CT scans of 10 patients from the TROG 08.03 RAVES trial. The CTV, rectum, and bladder were contoured independently by three experienced observers. Using these contours reference simultaneous truth and performance level estimation (STAPLE) volumes were established. Additional CTVs were generated using an atlas algorithm based on a single benchmark case with 42 manual contours. Volumetric-modulated arc therapy (VMAT) treatment plans were generated for the observer, atlas, and reference volumes. The dosimetry was evaluated using radiobiological metrics. Correlations between contouring similarity and dosimetry metrics were calculated using Spearman coefficient (Γ). To access impact of variations in planning target volume (PTV) margin, the STAPLE PTV was uniformly contracted and expanded, with plans created for each PTV volume. STAPLE dose-volume histograms (DVHs) were exported for plans generated based on the contracted/expanded volumes, and dose-volume metrics assessed.Mainresults. The study found no strong correlations between the considered similarity metrics and modelled outcomes. Moderate correlations (0.5 <Γ< 0.7) were observed for Dice similarity coefficient, Jaccard, and mean distance to agreement metrics and rectum toxicities. The observations of this study indicate a tendency for variations in CTV contraction/expansion below 5 mm to result in minor dosimetric impacts.Significance. Contouring similarity metrics must be used with caution when interpreting them as indicators of treatment plan variation. For post-prostatectomy VMAT patients, this work showed variations in contours with an expansion/contraction of less than 5 mm did not lead to notable dosimetric differences, this should be explored in a larger dataset to assess generalisability.
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Affiliation(s)
- Viet Le Bao
- South Western Clinical School, University of New South Wales, Sydney, Australia
- Ingham Institute for Applied Medical Research, Sydney, Australia
| | - Annette Haworth
- Institute of Medical Physics, School of Physics, University of Sydney, Australia
| | - Jason Dowling
- South Western Clinical School, University of New South Wales, Sydney, Australia
- Ingham Institute for Applied Medical Research, Sydney, Australia
| | - Amy Walker
- South Western Clinical School, University of New South Wales, Sydney, Australia
- Ingham Institute for Applied Medical Research, Sydney, Australia
- Liverpool and Macarthur Cancer Therapy Centres, Sydney, Australia
- Centre for Medical Radiation Physics, University of Wollongong, Wollongong, Australia
| | - Sankar Arumugam
- South Western Clinical School, University of New South Wales, Sydney, Australia
- Ingham Institute for Applied Medical Research, Sydney, Australia
- Liverpool and Macarthur Cancer Therapy Centres, Sydney, Australia
| | - Michael Jameson
- St Vincent's Clinical School, University of New South Wales, Sydney, Australia
- GenesisCare, Sydney, NSW, Australia
| | - Phillip Chlap
- South Western Clinical School, University of New South Wales, Sydney, Australia
- Ingham Institute for Applied Medical Research, Sydney, Australia
- Liverpool and Macarthur Cancer Therapy Centres, Sydney, Australia
| | - Kirsty Wiltshire
- Peter MacCallum Cancer Centre, Melbourne, Victoria, Australia
- Sir Peter MacCallum Department of Oncology, The University of Melbourne, Victoria, Australia
| | - Sarah Keats
- Ingham Institute for Applied Medical Research, Sydney, Australia
- Liverpool and Macarthur Cancer Therapy Centres, Sydney, Australia
| | - Kirrily Cloak
- South Western Clinical School, University of New South Wales, Sydney, Australia
- Ingham Institute for Applied Medical Research, Sydney, Australia
- Liverpool and Macarthur Cancer Therapy Centres, Sydney, Australia
| | - Mark Sidhom
- South Western Clinical School, University of New South Wales, Sydney, Australia
- Liverpool and Macarthur Cancer Therapy Centres, Sydney, Australia
| | | | - Lois Holloway
- South Western Clinical School, University of New South Wales, Sydney, Australia
- Ingham Institute for Applied Medical Research, Sydney, Australia
- Institute of Medical Physics, School of Physics, University of Sydney, Australia
- Liverpool and Macarthur Cancer Therapy Centres, Sydney, Australia
- Centre for Medical Radiation Physics, University of Wollongong, Wollongong, Australia
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Brand DH, Brüningk SC, Wilkins A, Naismith O, Gao A, Syndikus I, Dearnaley DP, Hall E, van As N, Tree AC, Gulliford S. Gastrointestinal Toxicity Prediction Not Influenced by Rectal Contour or Dose-Volume Histogram Definition. Int J Radiat Oncol Biol Phys 2023; 117:1163-1173. [PMID: 37433374 PMCID: PMC10680426 DOI: 10.1016/j.ijrobp.2023.07.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Revised: 06/01/2023] [Accepted: 07/03/2023] [Indexed: 07/13/2023]
Abstract
PURPOSE Rectal dose delivered during prostate radiation therapy is associated with gastrointestinal toxicity. Treatment plans are commonly optimized using rectal dose-volume constraints, often whole-rectum relative-volumes (%). We investigated whether improved rectal contouring, use of absolute-volumes (cc), or rectal truncation might improve toxicity prediction. METHODS AND MATERIALS Patients from the CHHiP trial (receiving 74 Gy/37 fractions [Fr] vs 60 Gy/20 Fr vs 57 Gy/19 Fr) were included if radiation therapy plans were available (2350/3216 patients), plus toxicity data for relevant analyses (2170/3216 patients). Whole solid rectum relative-volumes (%) dose-volume-histogram (DVH), as submitted by treating center (original contour), was assumed standard-of-care. Three investigational rectal DVHs were generated: (1) reviewed contour per CHHiP protocol; (2) original contour absolute volumes (cc); and (3) truncated original contour (2 versions; ±0 and ±2 cm from planning target volume [PTV]). Dose levels of interest (V30, 40, 50, 60, 70, 74 Gy) in 74 Gy arm were converted by equivalent-dose-in-2 Gy-Fr (EQD2α/β= 3 Gy) for 60 Gy/57 Gy arms. Bootstrapped logistic models predicting late toxicities (frequency G1+/G2+, bleeding G1+/G2+, proctitis G1+/G2+, sphincter control G1+, stricture/ulcer G1+) were compared by area-undercurve (AUC) between standard of care and the 3 investigational rectal definitions. RESULTS The alternative dose/volume parameters were compared with the original relative-volume (%) DVH of the whole rectal contour, itself fitted as a weak predictor of toxicity (AUC range, 0.57-0.65 across the 8 toxicity measures). There were no significant differences in toxicity prediction for: (1) original versus reviewed rectal contours (AUCs, 0.57-0.66; P = .21-.98); (2) relative- versus absolute-volumes (AUCs, 0.56-0.63; P = .07-.91); and (3) whole-rectum versus truncation at PTV ± 2 cm (AUCs, 0.57-0.65; P = .05-.99) or PTV ± 0 cm (AUCs, 0.57-0.66; P = .27-.98). CONCLUSIONS We used whole-rectum relative-volume DVH, submitted by the treating center, as the standard-of-care dosimetric predictor for rectal toxicity. There were no statistically significant differences in prediction performance when using central rectal contour review, with the use of absolute-volume dosimetry, or with rectal truncation relative to PTV. Whole-rectum relative-volumes were not improved upon for toxicity prediction and should remain standard-of-care.
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Affiliation(s)
- Douglas H Brand
- Division of Radiotherapy and Imaging, The Institute of Cancer Research, London, United Kingdom; Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom.
| | - Sarah C Brüningk
- Department of Health Science and Technology, ETH Zurich, Basel, Switzerland; Swiss Institute for Bioinformatics (SIB), Lausanne, Switzerland
| | - Anna Wilkins
- Division of Radiotherapy and Imaging, The Institute of Cancer Research, London, United Kingdom; Urology Unit
| | - Olivia Naismith
- Radiotherapy Trials QA Group (RTTQA), Royal Marsden NHS Foundation Trust, London, United Kingdom
| | - Annie Gao
- Division of Radiotherapy and Imaging, The Institute of Cancer Research, London, United Kingdom; Urology Unit
| | - Isabel Syndikus
- Radiotherapy Department, Clatterbridge Cancer Centre, Liverpool, United Kingdom
| | - David P Dearnaley
- Division of Radiotherapy and Imaging, The Institute of Cancer Research, London, United Kingdom; Urology Unit
| | - Emma Hall
- Clinical Trials and Statistics Unit, The Institute of Cancer Research, London, United Kingdom
| | - Nicholas van As
- Division of Radiotherapy and Imaging, The Institute of Cancer Research, London, United Kingdom; Urology Unit
| | - Alison C Tree
- Division of Radiotherapy and Imaging, The Institute of Cancer Research, London, United Kingdom; Urology Unit
| | - Sarah Gulliford
- Department of Medical Physics and Biomedical Engineering, University College London, London, United Kingdom; Department of Radiotherapy Physics, University College London Hospitals NHS Foundation Trust, London, United Kingdom
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Tong N, Gou S, Chen S, Yao Y, Yang S, Cao M, Kishan A, Sheng K. Multi-task edge-recalibrated network for male pelvic multi-organ segmentation on CT images. Phys Med Biol 2021; 66:035001. [PMID: 33197901 DOI: 10.1088/1361-6560/abcad9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Automated male pelvic multi-organ segmentation on CT images is highly desired for applications, including radiotherapy planning. To further improve the performance and efficiency of existing automated segmentation methods, in this study, we propose a multi-task edge-recalibrated network (MTER-Net), which aims to overcome the challenges, including blurry boundaries, large inter-patient appearance variations, and low soft-tissue contrast. The proposed MTER-Net is equipped with the following novel components. (a) To exploit the saliency and stability of femoral heads, we employed a light-weight localization module to locate the target region and efficiently remove the complex background. (b) We add an edge stream to the regular segmentation stream to focus on processing the edge-related information, distinguish the organs with blurry boundaries, and then boost the overall segmentation performance. Between the regular segmentation stream and edge stream, we introduce an edge recalibration module at each resolution level to connect the intermediate layers and deliver the higher-level activations from the regular stream to the edge stream to denoise the irrelevant activations. (c) Finally, using a 3D Atrous Spatial Pyramid Pooling (ASPP) feature fusion module, we fuse the features at different scales in the regular stream and the predictions from the edge stream to form the final segmentation result. The proposed segmentation network was evaluated on 200 prostate cancer patient CT images with manually delineated contours of bladder, rectum, seminal vesicle, and prostate. The segmentation performance of the proposed method was quantitatively evaluated using three metrics including Dice similarity coefficient (DSC), average surface distance (ASD), and 95% surface distance (95SD). The proposed MTER-Net achieves average DSC of 86.35%, ASD of 1.09 mm, and 95SD of 3.53 mm on the four organs, which outperforms the state-of-the-art segmentation networks by a large margin. Specifically, the quantitative DSC evaluation results of the four organs are 96.49% (bladder), 86.39% (rectum), 76.38% (seminal vesicle), and 86.14% (prostate), respectively. In conclusion, we demonstrate that the proposed MTER-Net efficiently attains superior performance to state-of-the-art pelvic organ segmentation methods.
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Affiliation(s)
- Nuo Tong
- Key Lab of Intelligent Perception and Image Understanding of Ministry of Education, Xidian University, Xi'an, Shaanxi 710071, People's Republic of China
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Patel D, Tan A, Brown A, Pain T. Absence of prostate oedema obviates the need for delay between fiducial marker insertion and radiotherapy simulation. J Med Radiat Sci 2020; 67:302-309. [PMID: 32614152 PMCID: PMC7753875 DOI: 10.1002/jmrs.412] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 04/16/2020] [Accepted: 05/20/2020] [Indexed: 11/29/2022] Open
Abstract
INTRODUCTION Fiducial markers (FMs) are commonly inserted into the prostate for image guided radiation therapy. This study aimed to quantify prostate oedema immediately following FM insertion compared to prostate volumes measured a week later, at the time of simulation for radiation therapy. METHODS Thirty patients underwent a verification computed tomography (VCT) scan in treatment position immediately after the fiducial insertion and their planning computed tomography scan (PCT) one week after. Patient data sets were retrospectively evaluated, comparing prostate volumes and planning target volumes (PTV). Volumes were delineated by a single radiation oncologist, blinded to whether the scan was VCT or PCT. Distances between the FMs were measured on both scans. Descriptive statistics described the data, DICE similarity co-efficient (DSC) calculated, and paired t-tests were used to compare paired data. RESULTS The median prostate volume was 35.09 cc and 36.31 cc for VCT and PCT data sets, respectively, and median PTV was 118.56 cc and 127.04 cc for VCT and PCT, respectively. There was no significant difference in prostate volumes (P = 0.3037) or PTV (P = 0.1279), with a DSC of 0.87 (range 0.76-0.91) and 0.91 (range 0.85 to 0.95), respectively. Similarly, there was no significant difference in distance between fiducial markers (P > 0.05). CONCLUSION This study demonstrates no statistically significant difference in prostate or PTV volumes (P > 0.05) between the CT acquired at fiducial marker insertion compared with the CT acquired a week later. Therefore, oedema is not significant enough to justify a delay between FM insertion and simulation.
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Affiliation(s)
- Deepti Patel
- Townsville Cancer Centre, Townsville University HospitalTownsvilleQueenslandAustralia
| | - Alex Tan
- Townsville Cancer Centre, Townsville University HospitalTownsvilleQueenslandAustralia
- James Cook UniversityTownsvilleQueenslandAustralia
| | - Amy Brown
- Townsville Cancer Centre, Townsville University HospitalTownsvilleQueenslandAustralia
| | - Tilley Pain
- James Cook UniversityTownsvilleQueenslandAustralia
- Townsville University HospitalTownsvilleQueenslandAustralia
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Barber J, Yuen J, Jameson M, Schmidt L, Sykes J, Gray A, Hardcastle N, Choong C, Poder J, Walker A, Yeo A, Archibald‐Heeren B, Harrison K, Haworth A, Thwaites D. Deforming to Best Practice: Key considerations for deformable image registration in radiotherapy. J Med Radiat Sci 2020; 67:318-332. [PMID: 32741090 PMCID: PMC7754021 DOI: 10.1002/jmrs.417] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 05/15/2020] [Accepted: 06/12/2020] [Indexed: 12/11/2022] Open
Abstract
Image registration is a process that underlies many new techniques in radiation oncology - from multimodal imaging and contour propagation in treatment planning to dose accumulation throughout treatment. Deformable image registration (DIR) is a subset of image registration subject to high levels of complexity in process and validation. A need for local guidance to assist in high-quality utilisation and best practice was identified within the Australian community, leading to collaborative activity and workshops. This report communicates the current limitations and best practice advice from early adopters to help guide those implementing DIR in the clinic at this early stage. They are based on the state of image registration applications in radiotherapy in Australia and New Zealand (ANZ), and consensus discussions made at the 'Deforming to Best Practice' workshops in 2018. The current status of clinical application use cases is presented, including multimodal imaging, automatic segmentation, adaptive radiotherapy, retreatment, dose accumulation and response assessment, along with uptake, accuracy and limitations. Key areas of concern and preliminary suggestions for commissioning, quality assurance, education and training, and the use of automation are also reported. Many questions remain, and the radiotherapy community will benefit from continued research in this area. However, DIR is available to clinics and this report is intended to aid departments using or about to use DIR tools now.
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Affiliation(s)
- Jeffrey Barber
- Sydney West Radiation Oncology NetworkBlacktown and WestmeadNSWAustralia
- Institute of Medical PhysicsUniversity of SydneySydneyNSWAustralia
| | - Johnson Yuen
- St George Cancer Care CentreSydneyNSWAustralia
- Ingham Institute for Applied Medical ResearchSydneyNSWAustralia
- South Western Clinical SchoolThe University of New South WalesSydneyNSWAustralia
| | - Michael Jameson
- Liverpool and Macarthur Cancer Therapy CentresSydneyNSWAustralia
- Ingham Institute for Applied Medical ResearchSydneyNSWAustralia
- South Western Clinical SchoolThe University of New South WalesSydneyNSWAustralia
| | | | - Jonathan Sykes
- Sydney West Radiation Oncology NetworkBlacktown and WestmeadNSWAustralia
- Institute of Medical PhysicsUniversity of SydneySydneyNSWAustralia
| | - Alison Gray
- Liverpool and Macarthur Cancer Therapy CentresSydneyNSWAustralia
- Ingham Institute for Applied Medical ResearchSydneyNSWAustralia
- South Western Clinical SchoolThe University of New South WalesSydneyNSWAustralia
| | - Nicholas Hardcastle
- Peter MacCallum Cancer CentreVictoriaAustralia
- Physical SciencesPeter MacCallum Cancer CentreVICAustralia
| | - Callie Choong
- Liverpool and Macarthur Cancer Therapy CentresSydneyNSWAustralia
| | - Joel Poder
- St George Cancer Care CentreSydneyNSWAustralia
- Physical SciencesPeter MacCallum Cancer CentreVICAustralia
| | - Amy Walker
- Liverpool and Macarthur Cancer Therapy CentresSydneyNSWAustralia
- Ingham Institute for Applied Medical ResearchSydneyNSWAustralia
- South Western Clinical SchoolThe University of New South WalesSydneyNSWAustralia
| | - Adam Yeo
- Peter MacCallum Cancer CentreVictoriaAustralia
- RMIT UniversityMelbourneVICAustralia
| | | | | | - Annette Haworth
- Institute of Medical PhysicsUniversity of SydneySydneyNSWAustralia
| | - David Thwaites
- Sydney West Radiation Oncology NetworkBlacktown and WestmeadNSWAustralia
- Institute of Medical PhysicsUniversity of SydneySydneyNSWAustralia
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Thor M, Apte A, Haq R, Iyer A, LoCastro E, Deasy JO. Using Auto-Segmentation to Reduce Contouring and Dose Inconsistency in Clinical Trials: The Simulated Impact on RTOG 0617. Int J Radiat Oncol Biol Phys 2020; 109:1619-1626. [PMID: 33197531 DOI: 10.1016/j.ijrobp.2020.11.011] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 10/14/2020] [Accepted: 11/05/2020] [Indexed: 12/25/2022]
Abstract
PURPOSE Contouring inconsistencies are known but understudied in clinical radiation therapy trials. We applied auto-contouring to the Radiation Therapy Oncology Group (RTOG) 0617 dose escalation trial data. We hypothesized that the trial heart doses were higher than reported due to inconsistent and insufficient heart segmentation. We tested our hypothesis by comparing doses between deep-learning (DL) segmented hearts and trial hearts. METHODS AND MATERIALS The RTOG 0617 data were downloaded from The Cancer Imaging Archive; the 442 patients with trial hearts and dose distributions were included. All hearts were resegmented using our DL pipeline and quality assured to meet the requirements for clinical implementation. Dose (V5%, V30%, and mean heart dose) was compared between the 2 sets of hearts (Wilcoxon signed-rank test). Each dose metric was associated with overall survival (Cox proportional hazards). Lastly, 18 volume similarity metrics were assessed for the hearts and correlated with |DoseDL - DoseRTOG0617| (linear regression; significance: P ≤ .0028; corrected for 18 tests). RESULTS Dose metrics were significantly higher for DL hearts compared with trial hearts (eg, mean heart dose: 15 Gy vs 12 Gy; P = 5.8E-16). All 3 DL heart dose metrics were stronger overall survival predictors than those of the trial hearts (median, P = 2.8E-5 vs 2.0E-4). Thirteen similarity metrics explained |DoseDL - DoseRTOG0617|; the axial distance between the 2 centers of mass was the strongest predictor (CENTAxial; median, R2 = 0.47; P = 6.1E-62). CENTAxial agreed with the qualitatively identified inconsistencies in the superior direction. The trial's qualitative heart contouring score was not correlated with |DoseDL - DoseRTOG0617| (median, R2 = 0.01; P = .02) or with any of the similarity metrics (median, Rs = 0.13 [range, -0.22 to 0.31]). CONCLUSIONS Using a coherent heart definition, as enabled through our open-source DL algorithm, the trial heart doses in RTOG 0617 were found to be significantly higher than previously reported, which may have led to an even more rapid mortality accumulation. Auto-segmentation is likely to reduce contouring and dose inconsistencies and increase the quality of clinical RT trials.
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Affiliation(s)
- Maria Thor
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York.
| | - Aditya Apte
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Rabia Haq
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Aditi Iyer
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Eve LoCastro
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York
| | - Joseph O Deasy
- Department of Medical Physics, Memorial Sloan Kettering Cancer Center, New York, New York
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Roach D, Holloway LC, Jameson MG, Dowling JA, Kennedy A, Greer PB, Krawiec M, Rai R, Denham J, De Leon J, Lim K, Berry ME, White RT, Bydder SA, Tan HT, Croker JD, McGrath A, Matthews J, Smeenk RJ, Ebert MA. Multi-observer contouring of male pelvic anatomy: Highly variable agreement across conventional and emerging structures of interest. J Med Imaging Radiat Oncol 2019; 63:264-271. [PMID: 30609205 DOI: 10.1111/1754-9485.12844] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Accepted: 11/27/2018] [Indexed: 12/16/2022]
Abstract
INTRODUCTION This study quantified inter-observer contouring variations for multiple male pelvic structures, many of which are of emerging relevance for prostate cancer radiotherapy progression and toxicity response studies. METHODS Five prostate cancer patient datasets (CT and T2-weighted MR) were distributed to 13 observers for contouring. CT structures contoured included the clinical target volume (CTV), seminal vesicles, rectum, colon, bowel bag, bladder and peri-rectal space (PRS). MR contours included CTV, trigone, membranous urethra, penile bulb, neurovascular bundle and multiple pelvic floor muscles. Contouring variations were assessed using the intraclass correlation coefficient (ICC), Dice similarity coefficient (DSC), and multiple additional metrics. RESULTS Clinical target volume (CT and MR), bladder, rectum and PRS contours showed excellent inter-observer agreement (median ICC = 0.97; 0.99; 1.00; 0.95; 0.90, DSC = 0.83 ± 0.05; 0.88 ± 0.05; 0.93 ± 0.03; 0.81 ± 0.07; 0.80 ± 0.06, respectively). Seminal vesicle contours were more variable (ICC = 0.75, DSC = 0.73 ± 0.14), while colon and bowel bag contoured volumes were consistent (ICC = 0.97; 0.97), but displayed poor overlap (DSC = 0.58 ± 0.22; 0.67 ± 0.21). Smaller MR structures showed significant inter-observer variations, with poor overlap for trigone, membranous urethra, penile bulb, and left and right neurovascular bundles (DSC = 0.44 ± 0.22; 0.41 ± 0.21; 0.66 ± 0.21; 0.16 ± 0.17; 0.15 ± 0.15). Pelvic floor muscles recorded moderate to strong inter-observer agreement (ICC = 0.50-0.97), although large outlier variations were observed. CONCLUSIONS Inter-observer contouring variation was significant for multiple pelvic structures contoured on MR.
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Affiliation(s)
- Dale Roach
- Faculty of Medicine, University of New South Wales, Sydney, New South Wales, Australia.,Ingham Institute for Applied Medical Research, Sydney, New South Wales, Australia
| | - Lois C Holloway
- Faculty of Medicine, University of New South Wales, Sydney, New South Wales, Australia.,Ingham Institute for Applied Medical Research, Sydney, New South Wales, Australia.,Centre for Medical Radiation Physics, University of Wollongong, Wollongong, New South Wales, Australia.,Department of Radiation Oncology, Liverpool and Macarthur Cancer Therapy Centres, New South Wales, Australia
| | - Michael G Jameson
- Faculty of Medicine, University of New South Wales, Sydney, New South Wales, Australia.,Ingham Institute for Applied Medical Research, Sydney, New South Wales, Australia.,Centre for Medical Radiation Physics, University of Wollongong, Wollongong, New South Wales, Australia.,Department of Radiation Oncology, Liverpool and Macarthur Cancer Therapy Centres, New South Wales, Australia
| | - Jason A Dowling
- Faculty of Medicine, University of New South Wales, Sydney, New South Wales, Australia.,Centre for Medical Radiation Physics, University of Wollongong, Wollongong, New South Wales, Australia.,Australian e-Health Research Centre, CSIRO, Royal Brisbane Hospital, Brisbane, Queensland, Australia.,School of Mathematical and Physical Sciences, University of Newcastle, Newcastle, New South Wales, Australia
| | - Angel Kennedy
- Radiation Oncology, Sir Charles Gairdner Hospital, Perth, Western Australia, Australia
| | - Peter B Greer
- School of Mathematical and Physical Sciences, University of Newcastle, Newcastle, New South Wales, Australia.,Calvary Mater Newcastle Hospital, Newcastle, New South Wales, Australia
| | - Michele Krawiec
- Radiation Oncology, Sir Charles Gairdner Hospital, Perth, Western Australia, Australia
| | - Robba Rai
- Faculty of Medicine, University of New South Wales, Sydney, New South Wales, Australia.,Ingham Institute for Applied Medical Research, Sydney, New South Wales, Australia.,Department of Radiation Oncology, Liverpool and Macarthur Cancer Therapy Centres, New South Wales, Australia
| | - Jim Denham
- School of Medicine and Population Health, University of Newcastle, Newcastle, New South Wales, Australia
| | - Jeremiah De Leon
- Illawarra Cancer Care Centre, Wollongong, New South Wales, Australia
| | - Karen Lim
- Department of Radiation Oncology, Liverpool and Macarthur Cancer Therapy Centres, New South Wales, Australia.,South Western Sydney Clinical School, University of New South Wales, Sydney, New South Wales, Australia
| | - Megan E Berry
- Department of Radiation Oncology, Liverpool and Macarthur Cancer Therapy Centres, New South Wales, Australia.,South Western Sydney Clinical School, University of New South Wales, Sydney, New South Wales, Australia
| | - Rohen T White
- Radiation Oncology, Sir Charles Gairdner Hospital, Perth, Western Australia, Australia
| | - Sean A Bydder
- Radiation Oncology, Sir Charles Gairdner Hospital, Perth, Western Australia, Australia
| | - Hendrick T Tan
- Radiation Oncology, Sir Charles Gairdner Hospital, Perth, Western Australia, Australia
| | | | - Alycea McGrath
- Radiation Oncology, Sir Charles Gairdner Hospital, Perth, Western Australia, Australia
| | - John Matthews
- Radiation Oncology, Auckland City Hospital, Auckland, New Zealand
| | - Robert J Smeenk
- Department of Radiation Oncology, Radboud University Medical Centre, Nijmegen, The Netherlands
| | - Martin A Ebert
- Centre for Medical Radiation Physics, University of Wollongong, Wollongong, New South Wales, Australia.,Radiation Oncology, Sir Charles Gairdner Hospital, Perth, Western Australia, Australia.,School of Physics and Astrophysics, Faculty of Science, University of Western Australia, Perth, Western Australia, Australia
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