scholarly journals Reduction of inter-observer differences in the delineation of the target in spinal metastases SBRT using an automatic contouring dedicated system

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Niccolò Giaj-Levra ◽  
Vanessa Figlia ◽  
Francesco Cuccia ◽  
Rosario Mazzola ◽  
Luca Nicosia ◽  
...  
Keyword(s):  
Organs At Risk ◽  
Performance Status ◽  
Spinal Metastases ◽  
Dice Similarity Coefficient ◽  
Normal Tissues ◽  
Correct Definition ◽  
Target Definition ◽  
Target Volumes ◽  
Treatment Volume ◽  
Automatic Contouring

Abstract Background Approximately one third of cancer patients will develop spinal metastases, that can be associated with back pain, neurological symptoms and deterioration in performance status. Stereotactic radiosurgery (SRS) and stereotactic body radiotherapy (SBRT) have been offered in clinical practice mainly for the management of oligometastatic and oligoprogressive patients, allowing the prescription of high total dose delivered in one or few sessions to small target volumes, minimizing the dose exposure of normal tissues. Due to the high delivered doses and the proximity of critical organs at risk (OAR) such as the spinal cord, the correct definition of the treatment volume becomes even more important in SBRT treatment, thus making it necessary to standardize the method of target definition and contouring, through the adoption of specific guidelines and specific automatic contouring tools. An automatic target contouring system for spine SBRT is useful to reduce inter-observer differences in target definition. In this study, an automatic contouring tool was evaluated. Methods Simulation CT scans and MRI data of 20 patients with spinal metastases were evaluated. To evaluate the advantage of the automatic target contouring tool (Elements SmartBrush Spine), which uses the identification of different densities within the target vertebra, we evaluated the agreement of the contours of 20 spinal target (2 cervical, 9 dorsal and 9 lumbar column), outlined by three independent observers using the automatic tool compared to the contours obtained manually, and measured by DICE similarity coefficient. Results The agreement of GTV contours outlined by independent operators was superior with the use of the automatic contour tool compared to manually outlined contours (mean DICE coefficient 0.75 vs 0.57, p = 0.048). Conclusions The dedicated contouring tool allows greater precision and reduction of inter-observer differences in the delineation of the target in SBRT spines. Thus, the evaluated system could be useful in the setting of spinal SBRT to reduce uncertainties of contouring increasing the level of precision on target delivered doses.

Stereotactic body radiotherapy for T1 glottic cancer: dosimetric data in 27 consecutive patients

2021 ◽  
pp. 030089162110004
Author(s):  
Giuseppe Sanguineti ◽  
Raul Pellini ◽  
Antonello Vidiri ◽  
Simona Marzi ◽  
Pasqualina D’Urso ◽  
...  
Keyword(s):  
Stereotactic Body Radiotherapy ◽  
Organs At Risk ◽  
Glottic Cancer ◽  
True Vocal Cord ◽  
Dosimetric Data ◽  
Planning Treatment ◽  
Target Volumes ◽  
Treatment Volume ◽  
Planning Treatment Volume ◽  
Prospective Phase

Aim: Because the clinical feasibility of stereotactic body radiotherapy (SBRT) for early glottic cancer (T1) is controversial, we report dosimetric results in 27 consecutive patients from a prospective phase I and II study that started in 2017. Methods: In our approach, only the parts of the true vocal cord containing cancer and those immediately adjacent are planned to be treated to 36 Gy and 30 Gy, respectively, in 3 fractions. Several dosimetric metrics for both target volumes and organs at risk were extracted from individual plans and results were compared to those achieved by other authors in a similar setting. Results: Proper coverage was reached at planning in 2/3 of planning treatment volume 30 Gy, but only 4 planning treatment volume 36 Gy; conversely, the maximum dose objective was met for most of the patients on either arytenoid cartilage, but this was not the case for 51.9% and 96.3% of cricoid and thyroid cartilages, respectively. Our dosimetric results are similar to if not better than those achieved by others. Conclusion: SBRT in 3 fractions for T1 glottic lesions is dosimetrically challenging. Clinical validation is awaited.

Evaluation of the impact of teaching on delineation variation during a virtual stereotactic ablative radiotherapy contouring workshop

2021 ◽  
pp. 1-8
Author(s):  
Finbar Slevin ◽  
Romélie Rieu ◽  
Matthew Beasley ◽  
Richard Speight ◽  
Katharine Aitken ◽  
...  
Keyword(s):  
Organs At Risk ◽  
Primary Lung Cancer ◽  
Target Volume ◽  
Pelvic Bone ◽  
Stereotactic Ablative Radiotherapy ◽  
Dice Similarity Coefficient ◽  
Multiple Target ◽  
Pelvic Node ◽  
Target Volumes ◽  
The Impact

Abstract Introduction: Variation in delineation of target volumes/organs at risk (OARs) is well recognised in radiotherapy and may be reduced by several methods including teaching. We evaluated the impact of teaching on contouring variation for thoracic/pelvic stereotactic ablative radiotherapy (SABR) during a virtual contouring workshop. Materials and methods: Target volume/OAR contours produced by workshop participants for three cases were evaluated against reference contours using DICE similarity coefficient (DSC) and line domain error (LDE) metrics. Pre- and post-workshop DSC results were compared using Wilcoxon signed ranks test to determine the impact of teaching during the workshop. Results: Of 50 workshop participants, paired pre- and post-workshop contours were available for 21 (42%), 20 (40%) and 22 (44%) participants for primary lung cancer, pelvic bone metastasis and pelvic node metastasis cases, respectively. Statistically significant improvements post-workshop in median DSC and LDE results were observed for 6 (50%) and 7 (58%) of 12 structures, respectively, although the magnitude of DSC/LDE improvement was modest in most cases. An increase in median DSC post-workshop ≥0·05 was only observed for GTVbone, IGTVlung and SacralPlex, and reduction in median LDE > 1 mm was only observed for GTVbone, CTVbone and SacralPlex. Post-workshop, median DSC values were >0·7 for 75% of structures. For 92% of the structures, post-workshop contours were considered to be acceptable or within acceptable variation following review by the workshop faculty. Conclusions: This study has demonstrated that virtual SABR contouring training is feasible and was associated with some improvements in contouring variation for multiple target volumes/OARs.

scholarly journals Management of recurrent or progressive spinal metastases: reirradiation techniques and surgical principles

2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. i45-i53
Author(s):  
Rupesh Kotecha ◽  
Nicolas Dea ◽  
Jay S Detsky ◽  
Arjun Sahgal
Keyword(s):  
Progressive Disease ◽  
Organs At Risk ◽  
Methodological Approach ◽  
Spinal Metastases ◽  
Multidisciplinary Care ◽  
Rehabilitation Medicine ◽  
Surgical Approaches ◽  
Mechanical Instability ◽  
Conventional Radiotherapy ◽  
Treated Site

Abstract With the growing incidence of new cases and the increasing prevalence of patients living longer with spine metastasis, a methodological approach to the management of patients with recurrent or progressive disease is increasing in relevance and importance in clinical practice. As a result, disease management has evolved in these patients using advanced surgical and radiotherapy technologies. Five key goals in the management of patients with spine metastases include providing pain relief, controlling metastatic disease at the treated site, improving neurologic deficits, maintaining or improving functional status, and minimizing further mechanical instability. The focus of this review is on advanced reirradiation techniques, given that the majority of patients will be treated with upfront conventional radiotherapy and further treatment on progression is often limited by the cumulative tolerance of nearby organs at risk. This review will also discuss novel surgical approaches such as separation surgery, minimally invasive percutaneous instrumentation, and laser interstitial thermal therapy, which is increasingly being coupled with spine reirradiation to maximize outcomes in this patient population. Lastly, given the complexities of managing recurrent spinal disease, this review emphasizes the importance of multidisciplinary care from neurosurgery, radiation oncology, medical oncology, neuro-oncology, rehabilitation medicine, and palliative care.

scholarly journals Prospective cohort study of surgical outcome for spinal metastases in patients aged 70 years or older

2020 ◽  
Vol 102-B (12) ◽  
pp. 1709-1716
Author(s):  
Yutaro Kanda ◽  
Kenichiro Kakutani ◽  
Yoshitada Sakai ◽  
Takashi Yurube ◽  
Shingo Miyazaki ◽  
...  
Keyword(s):  
Quality Of Life ◽  
Performance Status ◽  
Eastern Cooperative Oncology Group ◽  
Spinal Metastases ◽  
Palliative Surgery ◽  
Advanced Age ◽  
Health State ◽  
Survival Times ◽  
The Mean

Aims With recent progress in cancer treatment, the number of advanced-age patients with spinal metastases has been increasing. It is important to clarify the influence of advanced age on outcomes following surgery for spinal metastases, especially with a focus on subjective health state values. Methods We prospectively analyzed 101 patients with spinal metastases who underwent palliative surgery from 2013 to 2016. These patients were divided into two groups based on age (< 70 years and ≥ 70 years). The Eastern Cooperative Oncology Group (ECOG) performance status (PS), Barthel index (BI), and EuroQol-5 dimension (EQ-5D) score were assessed at study enrolment and at one, three, and six months after surgery. The survival times and complications were also collected. Results In total, 65 patients were aged < 70 years (mean 59.6 years; 32 to 69) and 36 patients were aged ≥ 70 years (mean 75.9 years; 70 to 90). In both groups, the PS improved from PS3 to PS1 by spine surgery, the mean BI improved from < 60 to > 80 points, and the mean EQ-5D score improved from 0.0 to > 0.7 points. However, no significant differences were found in the improvement rates and values of the PS, BI, and EQ-5D score at any time points between the two groups. The PS, BI, and EQ-5D score improved throughout the follow-up period in approximately 90% of patients in each group. However, the improved PS, BI, and EQ-5D scores subsequently deteriorated in some patients, and the redeterioration rate of the EQ-5D was significantly higher in patients aged ≥ 70 than < 70 years (p = 0.027). Conclusion Palliative surgery for spinal metastases improved the PS, activities of daily living, and quality of life, regardless of age. However, clinicians should be aware of the higher risk of redeterioration of the quality of life in advanced-age patients. Cite this article: Bone Joint J 2020;102-B(12):1709–1716.

scholarly journals Feasibility of Continual Deep Learning-Based Segmentation for Personalized Adaptive Radiation Therapy in Head and Neck Area

Cancers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 702
Author(s):  
Nalee Kim ◽  
Jaehee Chun ◽  
Jee Suk Chang ◽  
Chang Geol Lee ◽  
Ki Chang Keum ◽  
...  
Keyword(s):  
Deep Learning ◽  
Head And Neck ◽  
Organs At Risk ◽  
Subjective Assessment ◽  
Turing Test ◽  
Similar Rate ◽  
Dice Similarity Coefficient ◽  
Adaptive Planning ◽  
Test Set ◽  
Using Data

This study investigated the feasibility of deep learning-based segmentation (DLS) and continual training for adaptive radiotherapy (RT) of head and neck (H&N) cancer. One-hundred patients treated with definitive RT were included. Based on 23 organs-at-risk (OARs) manually segmented in initial planning computed tomography (CT), modified FC-DenseNet was trained for DLS: (i) using data obtained from 60 patients, with 20 matched patients in the test set (DLSm); (ii) using data obtained from 60 identical patients with 20 unmatched patients in the test set (DLSu). Manually contoured OARs in adaptive planning CT for independent 20 patients were provided as test sets. Deformable image registration (DIR) was also performed. All 23 OARs were compared using quantitative measurements, and nine OARs were also evaluated via subjective assessment from 26 observers using the Turing test. DLSm achieved better performance than both DLSu and DIR (mean Dice similarity coefficient; 0.83 vs. 0.80 vs. 0.70), mainly for glandular structures, whose volume significantly reduced during RT. Based on subjective measurements, DLS is often perceived as a human (49.2%). Furthermore, DLSm is preferred over DLSu (67.2%) and DIR (96.7%), with a similar rate of required revision to that of manual segmentation (28.0% vs. 29.7%). In conclusion, DLS was effective and preferred over DIR. Additionally, continual DLS training is required for an effective optimization and robustness in personalized adaptive RT.

scholarly journals Investigation of whether in-room CT-based adaptive intracavitary brachytherapy for uterine cervical cancer is robust against interfractional location variations of organs and/or applicators

2016 ◽  
Vol 57 (6) ◽  
pp. 677-683 ◽  
Author(s):  
Yoshifumi Oku ◽  
Hidetaka Arimura ◽  
Tran Thi Thao Nguyen ◽  
Yoshiyuki Hiraki ◽  
Masahiko Toyota ◽  
...  
Keyword(s):  
Cervical Cancer ◽  
Radiation Treatment ◽  
Organs At Risk ◽  
Normal Tissue Complication Probability ◽  
Uterine Cervical Cancer ◽  
Intracavitary Brachytherapy ◽  
Conformity Index ◽  
Tumor Control ◽  
Tumor Control Probability ◽  
Target Volumes

Abstract This study investigates whether in-room computed tomography (CT)-based adaptive treatment planning (ATP) is robust against interfractional location variations, namely, interfractional organ motions and/or applicator displacements, in 3D intracavitary brachytherapy (ICBT) for uterine cervical cancer. In ATP, the radiation treatment plans, which have been designed based on planning CT images (and/or MR images) acquired just before the treatments, are adaptively applied for each fraction, taking into account the interfractional location variations. 2D and 3D plans with ATP for 14 patients were simulated for 56 fractions at a prescribed dose of 600 cGy per fraction. The standard deviations (SDs) of location displacements (interfractional location variations) of the target and organs at risk (OARs) with 3D ATP were significantly smaller than those with 2D ATP (P &lt; 0.05). The homogeneity index (HI), conformity index (CI) and tumor control probability (TCP) in 3D ATP were significantly higher for high-risk clinical target volumes than those in 2D ATP. The SDs of the HI, CI, TCP, bladder and rectum D2cc, and the bladder and rectum normal tissue complication probability (NTCP) in 3D ATP were significantly smaller than those in 2D ATP. The results of this study suggest that the interfractional location variations give smaller impacts on the planning evaluation indices in 3D ATP than in 2D ATP. Therefore, the 3D plans with ATP are expected to be robust against interfractional location variations in each treatment fraction.

scholarly journals PD-1 Inhibitor Maintenance Therapy Combined Iodine-125 Seed Implantation Successfully Salvage Recurrent Cervical Cancer after CCRT: A Case Report

2021 ◽  
Vol 28 (6) ◽  
pp. 4577-4586
Author(s):  
Guangchao Wei ◽  
Fuxin Guo ◽  
Ang Qu ◽  
Weijuan Jiang ◽  
Yuliang Jiang ◽  
...  
Keyword(s):  
Cervical Cancer ◽  
Partial Response ◽  
Checkpoint Inhibitors ◽  
Organs At Risk ◽  
Recurrence Rates ◽  
Recurrent Cervical Cancer ◽  
Seed Implantation ◽  
Normal Tissues ◽  
Gynecology And Obstetrics ◽  
Choice Of Treatment

Cervical cancer is the fourth most common cancer in females worldwide. Patients with stage III and IV cervical cancer based on the Federation of Gynecology and Obstetrics (FIGO) classification have higher recurrence rates. Because of organs at risk (OAR) protection and the low indication rate of salvage surgery, the choice of treatment is always challenging. Systemic chemotherapy is palliative and can be performed in conjunction with surgery or radiotherapy; however, it has no significant benefit to survival. Brachytherapy and stereotactic body radiotherapy (SBRT) are characterized by extremely high radiation doses applied to tumor cells while sparing the normal tissues. Several studies have investigated the efficacy of these technologies in recurrent cervical cancer and showed promising results. The immune checkpoint inhibitors approach was also investigated and showed promising results too. Herein, we report a case of a patient with cervical cancer that recurred five months after adjuvant chemotherapy and concurrent chemoradiotherapy. The disease prognosis after interstitial implantation brachytherapy (IIB) was determined. Then, the patient underwent radioactive 125I-seed implantation combined with PD-1 inhibitor treatment. The patient exhibited a partial response after seed implantation, and up to now, the duration of this partial response was 24 months.

scholarly journals Determination of Radiosurgery Treatment Volume for Intracranial Germ Cell Tumors (GCTS)

2020 ◽  
Vol 8 (3) ◽  
Author(s):  
Murat Beyzadeoglu ◽  
Ferrat Dincoglan ◽  
Omer Sager ◽  
Selcuk Demiral
Keyword(s):  
Germ Cell ◽  
Background Radiation ◽  
Germ Cell Tumors ◽  
Target Volume ◽  
Whole Brain Irradiation ◽  
Volume Determination ◽  
Radiation Oncologists ◽  
Intracranial Germ Cell Tumors ◽  
Target Definition ◽  
Treatment Volume

Background: Radiation therapy (RT) volumes for intracranial germ cell tumors (GCTs) may include focal treatment volumes, whole ventricle irradiation, whole brain irradiation, or irradiation of the entire neuroaxis. RT doses and volumes for management of primary intracranial GCTs have been an area of active research over the years. Improved sparing of critical organs by use of less extensive RT volumes and lower doses has been investigated for avoiding excessive morbidity of treatment. Herein, we assess intracranial GCT treatment volume determination. Methods: Treatment volume definition for intracranial GCT by incorporation of Magnetic Resonance Imaging (MRI) was comparatively assessed in our study. Reference volume for comparison purposes was defined after thorough assessment and collaboration of the board certified radiation oncologists. Definition of radiosurgery target volume was based solely on CT images or fusion of CT with MRI. Comparative evaluation of treatment volume determination was performed. Results: Ground truth target volume defined after thorough evaluation and collaboration of the board certified radiation oncologists was similar with treatment volume definition based on CT-MR fusion based imaging. Conclusions: In conclusion, radiosurgery treatment planning for intracranial GCTs may be improved by incorporation of MRI into target definition process. Clearly, further studies are warranted to draw firm conclusions on optimal target definition for intracranial GCT radiosurgery.  

scholarly journals Investigation of Autosegmentation Techniques on T2-Weighted MRI for Off-line Dose Reconstruction in MR-Linac Adapt to Position Workflow for Head and Neck Cancers

2021 ◽  
Author(s):  
Brigid A McDonald ◽  
Carlos Cardenas ◽  
Nicolette O'Connell ◽  
Sara Ahmed ◽  
Mohamed A. Naser ◽  
...  
Keyword(s):  
Head And Neck ◽  
Execution Time ◽  
Organs At Risk ◽  
Ground Truth ◽  
Dice Similarity Coefficient ◽  
Observer Variability ◽  
Dose Reconstruction ◽  
Inter Observer Variability ◽  
Significant Difference ◽  
Delivered Dose

Purpose: In order to accurately accumulate delivered dose for head and neck cancer patients treated with the Adapt to Position workflow on the 1.5T magnetic resonance imaging (MRI)-linear accelerator (MR-linac), the low-resolution T2-weighted MRIs used for daily setup must be segmented to enable reconstruction of the delivered dose at each fraction. In this study, our goal is to evaluate various autosegmentation methods for head and neck organs at risk (OARs) on on-board setup MRIs from the MR-linac for off-line reconstruction of delivered dose. Methods: Seven OARs (parotid glands, submandibular glands, mandible, spinal cord, and brainstem) were contoured on 43 images by seven observers each. Ground truth contours were generated using a simultaneous truth and performance level estimation (STAPLE) algorithm. 20 autosegmentation methods were evaluated in ADMIRE: 1-9) atlas-based autosegmentation using a population atlas library (PAL) of 5/10/15 patients with STAPLE, patch fusion (PF), random forest (RF) for label fusion; 10-19) autosegmentation using images from a patient's 1-4 prior fractions (individualized patient prior (IPP)) using STAPLE/PF/RF; 20) deep learning (DL) (3D ResUNet trained on 43 ground truth structure sets plus 45 contoured by one observer). Execution time was measured for each method. Autosegmented structures were compared to ground truth structures using the Dice similarity coefficient, mean surface distance, Hausdorff distance, and Jaccard index. For each metric and OAR, performance was compared to the inter-observer variability using Dunn's test with control. Methods were compared pairwise using the Steel-Dwass test for each metric pooled across all OARs. Further dosimetric analysis was performed on three high-performing autosegmentation methods (DL, IPP with RF and 4 fractions (IPP_RF_4), IPP with 1 fraction (IPP_1)), and one low-performing (PAL with STAPLE and 5 atlases (PAL_ST_5)). For five patients, delivered doses from clinical plans were recalculated on setup images with ground truth and autosegmented structure sets. Differences in maximum and mean dose to each structure between the ground truth and autosegmented structures were calculated and correlated with geometric metrics. Results: DL and IPP methods performed best overall, all significantly outperforming inter-observer variability and with no significant difference between methods in pairwise comparison. PAL methods performed worst overall; most were not significantly different from the inter-observer variability or from each other. DL was the fastest method (33 seconds per case) and PAL methods the slowest (3.7 - 13.8 minutes per case). Execution time increased with number of prior fractions/atlases for IPP and PAL. For DL, IPP_1, and IPP_RF_4, the majority (95%) of dose differences were within 250 cGy from ground truth, but outlier differences up to 785 cGy occurred. Dose differences were much higher for PAL_ST_5, with outlier differences up to 1920 cGy. Dose differences showed weak but significant correlations with all geometric metrics (R2 between 0.030 and 0.314). Conclusions: The autosegmentation methods offering the best combination of performance and execution time are DL and IPP_1. Dose reconstruction on on-board T2-weighted MRIs is feasible with autosegmented structures with minimal dosimetric variation from ground truth, but contours should be visually inspected prior to dose reconstruction in an end-to-end dose accumulation workflow.

Sign in / Sign up

Export Citation Format

Share Document