scholarly journals Comparison of the Gross Target Volumes Based on Diagnostic PET/CT for Primary Esophageal Cancer

2021 ◽  
Vol 11 ◽  
Author(s):  
Jingzhen Shi ◽  
Jianbin Li ◽  
Fengxiang Li ◽  
Yingjie Zhang ◽  
Yanluan Guo ◽  
...  
Keyword(s):  
Esophageal Cancer ◽  
Three Dimensional ◽  
Target Volume ◽  
Conformity Index ◽  
Ct Image ◽  
Thoracic Esophageal Cancer ◽  
Imaging Results ◽  
Pet Ct ◽  
Significant Difference ◽  
Target Volumes

BackgroundClinically, many esophageal cancer patients who planned for radiation therapy have already undergone diagnostic Positron-emission tomography/computed tomography (PET/CT) imaging, but it remains unclear whether these imaging results can be used to delineate the gross target volume (GTV) of the primary tumor for thoracic esophageal cancer (EC).MethodsSeventy-two patients diagnosed with thoracic EC had undergone prior PET/CT for diagnosis and three-dimensional CT (3DCT) for simulation. The GTV3D was contoured on the 3DCT image without referencing the PET/CT image. The GTVPET-ref was contoured on the 3DCT image referencing the PET/CT image. The GTVPET-reg was contoured on the deformed registration image derived from 3DCT and PET/CT. Differences in the position, volume, length, conformity index (CI), and degree of inclusion (DI) among the target volumes were determined.ResultsThe centroid distance in the three directions between two different GTVs showed no significant difference (P > 0.05). No significant difference was found among the groups in the tumor volume (P > 0.05). The median DI values of the GTVPET-reg and GTVPET-ref in the GTV3D were 0.82 and 0.86, respectively (P = 0.006). The median CI values of the GTV3D in the GTVPET-reg and GTVPET-ref were 0.68 and 0.72, respectively (P = 0.006).ConclusionsPET/CT can be used to optimize the definition of the target volume in EC. However, no significant difference was found between the GTVs delineated based on visual referencing or deformable registration whether using the volume or position. So, in the absence of planning PET–CT images, it is also feasible to delineate the GTV of primary thoracic EC with reference to the diagnostic PET–CT image.

scholarly journals Comparison of planning target volumes based on three-dimensional and four-dimensional CT imaging of thoracic esophageal cancer

2016 ◽  
Vol Volume 9 ◽  
pp. 4785-4791
Author(s):  
Wei Wang ◽  
Jianbin Li ◽  
Yingjie Zhang ◽  
Qian Shao ◽  
Min Xu ◽  
...  
Keyword(s):  
Esophageal Cancer ◽  
Three Dimensional ◽  
Ct Imaging ◽  
Thoracic Esophageal Cancer ◽  
Target Volumes

scholarly journals [F18] FDG-PET/CT for manual or semiautomated GTV delineation of the primary tumor for radiation therapy planning in patients with esophageal cancer: is it useful?

2020 ◽  
Author(s):  
Franziska Walter ◽  
Constanze Jell ◽  
Barbara Zollner ◽  
Claudia Andrae ◽  
Sabine Gerum ◽  
...  
Keyword(s):  
Esophageal Cancer ◽  
Primary Tumor ◽  
Fdg Pet ◽  
Interobserver Variability ◽  
Target Volume ◽  
Standardized Uptake Values ◽  
Positron Emission ◽  
Pet Ct ◽  
Significant Difference ◽  
Fdg Pet Ct

Abstract Background Target volume definition of the primary tumor in esophageal cancer is usually based on computed tomography (CT) supported by endoscopy and/or endoscopic ultrasound and can be difficult given the low soft-tissue contrast of CT resulting in large interobserver variability. We evaluated the value of a dedicated planning [F18] FDG-Positron emission tomography/computer tomography (PET/CT) for harmonization of gross tumor volume (GTV) delineation and the feasibility of semiautomated structures for planning purposes in a large cohort. Methods Patients receiving a dedicated planning [F18] FDG-PET/CT (06/2011–03/2016) were included. GTV was delineated on CT and on PET/CT (GTVCT and GTVPET/CT, respectively) by three independent radiation oncologists. Interobserver variability was evaluated by comparison of mean GTV and mean tumor lengths, and via Sørensen–Dice coefficients (DSC) for spatial overlap. Semiautomated volumes were constructed based on PET/CT using fixed standardized uptake values (SUV) thresholds (SUV30, 35, and 40) or background- and metabolically corrected PERCIST-TLG and Schaefer algorithms, and compared to manually delineated volumes. Results 45 cases were evaluated. Mean GTVCT and GTVPET/CT were 59.2/58.0 ml, 65.4/64.1 ml, and 60.4/59.2 ml for observers A–C. No significant difference between CT- and PET/CT-based delineation was found comparing the mean volumes or lengths. Mean Dice coefficients on CT and PET/CT were 0.79/0.77, 0.81/0.78, and 0.8/0.78 for observer pairs AB, AC, and BC, respectively, with no significant differences. Mean GTV volumes delineated semiautomatically with SUV30/SUV35/SUV40/Schaefer’s and PERCIST-TLG threshold were 69.1/23.9/18.8/18.6 and 70.9 ml. The best concordance of a semiautomatically delineated structure with the manually delineated GTVCT/GTVPET/CT was observed for PERCIST-TLG. Conclusion We were not able to show that the integration of PET/CT for GTV delineation of the primary tumor resulted in reduced interobserver variability. The PERCIST-TLG algorithm seemed most promising compared to other thresholds for further evaluation of semiautomated delineation of esophageal cancer.

scholarly journals Computed Tomography-Based Evaluation of Volume and Position Changes of the Target Region and Organs at Risk During Radiotherapy for Esophageal Cancer: A Pilot Study

2021 ◽  
Vol 11 ◽  
Author(s):  
Yi-mei Liu ◽  
Ying-lin Peng ◽  
Qi-wen Li ◽  
Guanzhu Shen ◽  
Ya-ru Ma ◽  
...  
Keyword(s):  
Computed Tomography ◽  
At Risk ◽  
Esophageal Cancer ◽  
Cancer Patients ◽  
Organs At Risk ◽  
Three Dimensional ◽  
Intensity Modulated Radiation Therapy ◽  
Conformal Radiotherapy ◽  
Target Volume ◽  
Target Volumes

ObjectiveTo analyze changes in volume and position of target regions and organs at risk (OARs) during radiotherapy for esophageal cancer patients.MethodsOverall, 16 esophageal cancer patients who underwent radiotherapy, including 10 cases of intensity-modulated radiation therapy (IMRT) and six of three-dimensional conformal radiotherapy (3D-CRT), were enrolled. The prescription doses for the planning target volumes (PTVs) were as follows: PTV1, 64 Gy/32 fractions; and PTV2, 46 Gy/23 fractions. Repeat computed tomography (CT) was performed for patients after the 5th, 10th, 15th, 20th, and 25th fractions. Delineation of the gross tumor volume (GTV) and OAR volume was determined using five repeat CTs performed by the same physician. The target and OAR volumes and centroid positions were recorded and used to analyze volume change ratio (VCR), center displacement (ΔD), and changes in the distance from the OAR centroid positions to the planned radiotherapy isocenter (distance to isocenter, DTI) during treatment.ResultsNo patient showed significant changes in target volume (TV) after the first week of radiotherapy (five fractions). However, TV gradually decreased over the following weeks, with the rate slowing after the fourth week (40 Gy). The comparison of TV from baseline to 40 Gy (20 fractions) showed that average GTVs decreased from 130.7 ± 63.1 cc to 92.1 ± 47.2 cc, with a VCR of −29.21 ± 13.96% (p<0.01), while the clinical target volume (CTV1) decreased from 276.7 ± 98.2 cc to 246.7 ± 87.2 cc, with a VCR of −10.34 ± 7.58% (p<0.01). As TVs decreased, ΔD increased and DTI decreased. After the fourth week of radiotherapy (40 Gy), centroids of GTV, CTV1, and prophylactic CTV (CTV2) showed average deviations in ΔD of 7.6 ± 4.0, 6.9 ± 3.4, and 6.0 ± 3.0 mm, respectively. The average DTI of the heart decreased by 4.53 mm (from 15.61 ± 2.96 cm to 15.16 ± 2.27 cm).ConclusionDuring radiotherapy for esophageal cancer, Targets and OARs change significantly in volume and position during the 2nd–4th weeks. Image-guidance and evaluation of dosimetric changes are recommended for these fractions of treatment to appropriate adjust treatment plans.

scholarly journals Organ motion in linac-based SBRT for glottic cancer

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Annarita Perillo ◽  
Valeria Landoni ◽  
Alessia Farneti ◽  
Giuseppe Sanguineti
Keyword(s):  
Early Stage ◽  
Displacement Vector ◽  
Thyroid Cartilage ◽  
Three Dimensional ◽  
Target Volume ◽  
Glottic Cancer ◽  
Organ Motion ◽  
Delivery Times ◽  
Significant Difference ◽  
Pre Treatment

Abstract Purpose The purpose of this study is to evaluate inter- and intra-fraction organ motion as well as to quantify clinical target volume (CTV) to planning target volume (PTV) margins to be adopted in the stereotactic treatment of early stage glottic cancer. Methods and materials Stereotactic body radiotherapy (SBRT) to 36 Gy in 3 fractions was administered to 23 patients with early glottic cancer T1N0M0. Patients were irradiated with a volumetric intensity modulated arc technique delivered with 6 MV FFF energy. Each patient underwent a pre-treatment cone beam computed tomography (CBCT) to correct the setup based on the thyroid cartilage position. Imaging was repeated if displacement exceeded 2 mm in any direction. CBCT imaging was also performed after each treatment arc as well as at the end of the delivery. Swallowing was allowed only during the beam-off time between arcs. CBCT images were reviewed to evaluate inter- and intra-fraction organ motion. The relationships between selected treatment characteristics, both beam-on and delivery times as well as organ motion were investigated. Results For the population systematic (Ʃ) and random (σ) inter-fraction errors were 0.9, 1.3 and 0.6 mm and 1.1, 1.3 and 0.7 mm in the left-right (X), cranio-caudal (Y) and antero-posterior (Z) directions, respectively. From the analysis of CBCT images acquired after treatment, systematic (Ʃ) and random (σ) intra-fraction errors resulted 0.7, 1.6 and 0.7 mm and 1.0, 1.5 and 0.6 mm in the X, Y and Z directions, respectively. Margins calculated from the intra-fraction errors were 2.4, 5.1 and 2.2 mm in the X, Y and Z directions respectively. A statistically significant difference was found for the displacement in the Z direction between patients irradiated with > 2 arcs versus ≤ 2 arcs, (MW test, p = 0.038). When analyzing mean data from CBCT images for the whole treatment, a significant correlation was found between the time of delivery and the three dimensional displacement vector (r = 0.489, p = 0.055), the displacement in the Y direction (r = 0.553, p = 0.026) and the subsequent margins to be adopted (r = 0.626, p = 0.009). Finally, displacements and the subsequent margins to be adopted in Y direction were significantly greater for treatments with more than 2 arcs (MW test p = 0.037 and p = 0.019, respectively). Conclusions In the setting of controlled swallowing during treatment delivery, intra-fraction motion still needs to be taken into account when planning with estimated CTV to PTV margins of 3, 5 and 3 mm in the X, Y and Z directions, respectively. Selected treatments may require additional margins.

scholarly journals Interobserver variability in target volume delineation in definitive radiotherapy for thoracic esophageal cancer: a multi-center study from China

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Xiao Chang ◽  
Wei Deng ◽  
Xin Wang ◽  
Zongmei Zhou ◽  
Jun Yang ◽  
...  
Keyword(s):  
Esophageal Cancer ◽  
Gross Tumor Volume ◽  
Tumor Volume ◽  
Interobserver Variability ◽  
Target Volume ◽  
Thoracic Esophageal Cancer ◽  
Target Volume Delineation ◽  
Cancer Centers ◽  
Definitive Radiotherapy ◽  
Volume Delineation

Abstract Purpose To investigate the interobserver variability (IOV) in target volume delineation of definitive radiotherapy for thoracic esophageal cancer (TEC) among cancer centers in China, and ultimately improve contouring consistency as much as possible to lay the foundation for multi-center prospective studies. Methods Sixteen cancer centers throughout China participated in this study. In Phase 1, three suitable cases with upper, middle, and lower TEC were chosen, and participants were asked to contour a group of gross tumor volume (GTV-T), nodal gross tumor volume (GTV-N) and clinical target volume (CTV) for each case based on their routine experience. In Phase 2, the same clinicians were instructed to follow a contouring protocol to re-contour another group of target volume. The variation of the target volume was analyzed and quantified using dice similarity coefficient (DSC). Results Sixteen clinicians provided routine volumes, whereas ten provided both routine and protocol volumes for each case. The IOV of routine GTV-N was the most striking in all cases, with the smallest DSC of 0.37 (95% CI 0.32–0.42), followed by CTV, whereas GTV-T showed high consistency. After following the protocol, the smallest DSC of GTV-N was improved to 0.64 (95% CI 0.45–0.83, P = 0.005) but the DSC of GTV-T and CTV remained constant in most cases. Conclusion Variability in target volume delineation was observed, but it could be significantly reduced and controlled using mandatory interventions.

scholarly journals 18F-FDG PET/CT Parameters for Predicting Prognosis in Esophageal Cancer Patients Treated With Concurrent Chemoradiotherapy

2021 ◽  
Vol 20 ◽  
pp. 153303382110246
Author(s):  
Seokmo Lee ◽  
Yunseon Choi ◽  
Geumju Park ◽  
Sunmi Jo ◽  
Sun Seong Lee ◽  
...  
Keyword(s):  
Esophageal Cancer ◽  
Cancer Patients ◽  
Fdg Pet ◽  
Concurrent Chemoradiotherapy ◽  
Curative Intent ◽  
Squamous Cell Esophageal Cancer ◽  
Pet Ct ◽  
Significant Difference ◽  
Fdg Pet Ct

Background and Aims: This study evaluated the prognostic value of 18F-fluorodeoxyglucose positron emission tomography with integrated computed tomography (18F-FDG PET/CT) performed before and after concurrent chemoradiotherapy (CCRT) in esophageal cancer. Methods: We analyzed the prognosis of 50 non-metastatic squamous cell esophageal cancer (T1-4N0-2) patients who underwent CCRT with curative intent at Inje University Busan Paik Hospital and Haeundae Paik Hospital from 2009 to 2019. Median total radiation dose was 54 Gy (range 34-66 Gy). Our aim was to investigate the relationship between PET/CT values and prognosis. The primary end point was progression-free survival (PFS). Results: The median follow-up period was 9.9 months (range 1.7-85.7). Median baseline maximum standard uptake value (SUVmax) was 14.2 (range 3.2-27.7). After treatment, 29 patients (58%) showed disease progression. The 3-year PFS and overall survival (OS) were 24.2% and 54.5%, respectively. PFS was significantly lower ( P = 0.015) when SUVmax of initial PET/CT exceeded 10 (n = 22). However, OS did not reach a significant difference based on maximum SUV ( P = 0.282). Small metabolic tumor volume (≤14.1) was related with good PFS ( P = 0.002) and OS ( P = 0.001). Small total lesion of glycolysis (≤107.3) also had a significant good prognostic effect on PFS ( P = 0.009) and OS ( P = 0.025). In a subgroup analysis of 18 patients with follow-up PET/CT, the patients with SUV max ≤3.5 in follow-up PET/CT showed longer PFS ( P = 0.028) than those with a maximum SUV >3.5. Conclusion: Maximum SUV of PET/CT is useful in predicting prognosis of esophageal cancer patients treated with CCRT. Efforts to find more effective treatments for patients at high risk of progression are still warranted.

scholarly journals Dosimetric Comparison of Three Radiotherapy Techniques in Irradiation of Left-Sided Breast Cancer Patients after Radical Mastectomy

2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Jian Hu ◽  
Guang Han ◽  
Yu Lei ◽  
Ximing Xu ◽  
Wei Ge ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cancer Patients ◽  
Volumetric Modulated Arc Therapy ◽  
Intensity Modulated Radiation Therapy ◽  
Radical Mastectomy ◽  
Target Volume ◽  
Conformity Index ◽  
Breast Cancer Patients ◽  
Ipsilateral Lung ◽  
Significant Difference

Introduction. This study is aimed at evaluating the dosimetric differences among target segmented planning (TSP), conventional 9-field intensity modulated radiation therapy (9FIMRT) planning, and volumetric modulated arc therapy (VMAT) planning for postmastectomy radiotherapy of left-sided breast cancer patients. Material and Methods. Fifteen left-sided breast cancer patients who underwent radical mastectomy were enrolled. In TSP, the planning target volume (PTV) was divided into four regions (supra/infraclavicular, chest wall, external mammary region, and internal mammary region), and each individual PTV region was treated with respective fixed fields. Results. The VMAT plans showed superior to PTV dose conformity index (CI), homogeneity index (HI), protection of the ipsilateral lung, monitor units (MUs), and maximum dose (Dmax) to the contralateral breast compared with TSP and 9FIMRT plans. The TSP provided better protection for Dmean of the heart and left ventricle (p<0.05). A dose for left anterior descending artery from the three techniques had no significant difference. Compared with the 9FIMRT plans, the V5Gy (%) and V10Gy (%) for the ipsilateral lung were significantly reduced with TSP and VMAT (p<0.05). The V5Gy (%) and V10Gy (%) for the ipsilateral lung turned out to be similar between VMAT and TSP techniques. Conclusions. Our study indicates that VMAT should be a better choice of radiotherapy for left-sided breast cancer patients after radical mastectomy. If VMAT is unavailable, 9FIMRT can achieve better CI and HI values and be more MU-efficient compared with TSP; however, TSP can effectively reduce the low dose volume of the ipsilateral lungs and heart.

scholarly journals Significance of Tumor Length as Prognostic Factor for Esophageal Cancer

2013 ◽  
Vol 98 (3) ◽  
pp. 234-240 ◽  
Author(s):  
Arife Zeybek ◽  
Abdullah Erdoğan ◽  
Kemal Hakan Gülkesen ◽  
Makbule Ergin ◽  
Alpay Sarper ◽  
...  
Keyword(s):  
Esophageal Cancer ◽  
Lymph Node ◽  
Specific Treatment ◽  
Disease Free Survival ◽  
Curative Surgery ◽  
Thoracic Esophageal Cancer ◽  
Clinicopathologic Characteristics ◽  
Term Survival ◽  
Tumor Length ◽  
Significant Difference

Abstract Our study indicated the relationship between tumor length and clinicopathologic characteristics as well as long-term survival in esophageal cancer. A total of 116 patients who underwent curative surgery for thoracic esophageal cancer with standard lymphadenectomy in 2 fields between 2000 and 2010 were included in the study. The medical records of these patients were retrospectively reviewed. The patients with tumor length ≥3 cm had a highly significant difference in the involvement of adventitia and lymph node stations. The patients with tumor length ≤3 cm had significantly lower rates of involvement of the adventitia and lymph node stations. Tumor length could have a significant impact on both the overall survival and disease-free survival of patients with resected esophageal carcinomas and may provide additional prognostic value to the current tumor, node, and metastasis staging system before patients receive any cancer-specific treatment.

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