scholarly journals Limited recurrence distance of glioblastoma under modern radiotherapy era

BMC Cancer ◽  
2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Ziwei Tu ◽  
Huifen Xiong ◽  
Yang Qiu ◽  
Guoqing Li ◽  
Li Wang ◽  
...  
Keyword(s):  
Tumor Volume ◽  
Planning System ◽  
Treatment Planning System ◽  
Target Area ◽  
Recurrent Lesion ◽  
Tumor Margins ◽  
Local Recurrences ◽  
Initial Tumor ◽  
Treatment Volume ◽  
Enhanced Imaging

Abstract Background The optimal treatment volume for Glioblastoma multiforme (GBM) is still a subject of debate worldwide. The current study was aimed to determine the distances between recurring tumors and the edge of primary lesions, and thereby provide evidence for accurate target area delineation. Methods Between October 2007 and March 2019, 68 recurrent patients with GBM were included in our study. We measured the distance from the initial tumor to the recurrent lesion of GBM patients by expanding the initial gross tumor volume (GTV) to overlap the center of recurrent lesion, with the help of the Pinnacle Treatment Planning System. Results Recurrences were local in 47(69.1%) patients, distant in 12(17.7%) patients, and both in 9(13.2%) patients. Factors significantly influencing local recurrence were age (P = 0.049), sex (P = 0.049), and the size of peritumoral edema (P = 0.00). A total number of 91 recurrent tumors were analyzed. All local recurrences occurred within 2 cm and 94.8% (55/58) occurred within 1 cm of the original GTV based on T1 enhanced imaging. All local recurrences occurred within 1.5 cm and 98.3%(57/58) occurred within 0.5 cm of the original GTV based on T2-FLAIR imaging. 90.9% (30/33) and 81.8% (27/33) distant recurrences occurred >3 cm of T1 enhanced and T2-Flair primary tumor margins, respectively. Conclusions The 1 cm margin from T1 enhanced lesions and 0.5 cm margin from T2-Flair abnormal lesions could cover 94.8 and 98.3% local recurrences respectively, which deserves further prospective study as a limited but effective target area.

scholarly journals Limited Recurrence Distance of Glioblastoma Under Modern Radiotherapy Era

2020 ◽  
Author(s):  
ZiWei Tu ◽  
Huifen Xiong ◽  
Yang Qiu ◽  
Guoqing Li ◽  
Li Wang ◽  
...  
Keyword(s):  
Tumor Volume ◽  
Planning System ◽  
Treatment Planning System ◽  
Target Area ◽  
Recurrent Lesion ◽  
Tumor Margins ◽  
Local Recurrences ◽  
Initial Tumor ◽  
Treatment Volume ◽  
Enhanced Imaging

Abstract Background: The optimal treatment volume for Glioblastoma multiforme (GBM) is still a subject of debate worldwide. The current study was aimed to determine the distances between recurring tumors and the edge of primary lesions, and thereby provide evidence for accurate target area delineation.Methods: Between October 2007 and March 2019, 68 recurrent patients with GBM were included in our study. We measured the distance from the initial tumor to the recurrent lesion of GBM patients by expanding the initial gross tumor volume (GTV) to overlap the center of recurrent lesion, with the help of the Pinnacle Treatment Planning System.Results: Recurrences were local in 56(82.3%) patients, distant in 21(30.9%) patients, and both in 9(13.2%) patients. Factors significantly influencing local recurrence were age (P = 0.049), sex (P = 0.049), and the size of peritumoral edema (P = 0.00). A total number of 91 recurrent tumors were analyzed. All local recurrences occurred within 2cm and 94.8% (55/58) occurred within 1cm of the original GTV based on T1 enhanced imaging. All local recurrences occurred within 1.5 cm and 98.3%(57/58) occurred within 0.5 cm of the original GTV based on T2-FLAIR imaging. 90.9% (30/33) and 81.8% (27/33) distant recurrences occurred ＞3 cm of T1 enhanced and T2-Flair primary tumor margins, respectively. Conclusions: The 1cm margin from T1 enhanced lesions and 0.5cm margin from T2-Flair abnormal lesions could cover 94.8% and 98.3% local recurrences respectively, which deserves further prospective study as a limited but effective target area.

scholarly journals Semi-supervised planning method for breast electronic tissue compensation treatments based on breast radius and separation

2020 ◽  
Vol 55 (1) ◽  
pp. 106-115
Author(s):  
Alexander R. Podgorsak ◽  
Lalith K. Kumaraswamy
Keyword(s):  
Penetration Depth ◽  
Treatment Plan ◽  
Planning System ◽  
Treatment Planning System ◽  
Breast Cancer Patients ◽  
User Input ◽  
Treatment Volume ◽  
Ct Simulation ◽  
Treatment Plans ◽  
Pre Treatment

AbstractBackgroundThe aim of the study was to develop and assess a technique for the optimization of breast electronic tissue compensation (ECOMP) treatment plans based on the breast radius and separation.Materials and methodsTen ECOMP plans for 10 breast cancer patients delivered at our institute were collected for this work. Pre-treatment CT-simulation images were anonymized and input to a framework for estimation of the breast radius and separation for each axial slice. Optimal treatment fluence was estimated based on the breast radius and separation, and a total beam fluence map for both medial and lateral fields was generated. These maps were then imported into the Eclipse Treatment Planning System and used to calculate a dose distribution. The distribution was compared to the original treatment hand-optimized by a medical dosimetrist. An additional comparison was performed by generating plans assuming a single tissue penetration depth determined by averaging the breast radius and separation over the entire treatment volume. Comparisons between treatment plans used the dose homogeneity index (HI; lower number is better).ResultsHI was non-inferior between our algorithm (HI = 12.6) and the dosimetrist plans (HI = 9.9) (p-value > 0.05), and was superior than plans obtained using a single penetration depth (HI = 17.0) (p-value < 0.05) averaged over the 10 collected plans. Our semi-supervised algorithm takes approximately 20 seconds for treatment plan generation and runs with minimal user input, which compares favorably with the dosimetrist plans that can take up to 30 minutes of attention for full optimization.ConclusionsThis work indicates the potential clinical utility of a technique for the optimization of ECOMP breast treatments.

Tumor volume as a prognostic factor in patients (pts) with locoregionally advanced head and neck squamous cell carcinoma (LAHNSCC) treated with induction chemotherapy (IC).

2017 ◽  
Vol 35 (15_suppl) ◽  
pp. e17507-e17507
Author(s):  
Daniel Moore Freitas Palhares ◽  
Fernando Coutinho Batista ◽  
Ana Lima Veneziani ◽  
Marcos Duarte Mattos ◽  
Augusto Elias Mamere ◽  
...  
Keyword(s):  
Head And Neck ◽  
Tumor Volume ◽  
Univariate Analysis ◽  
Stage Iv ◽  
Progression Free Survival ◽  
Primary Site ◽  
Planning System ◽  
Treatment Planning System ◽  
Definitive Treatment ◽  
Volumetric Change

e17507 Background: Tumor volume and the ratio of volumetric change have been demonstrated to have a prognostic role in head and neck cancers during definitive treatment in LAHNSCC. The aim of this study was to evaluate the prognostic value of tumor volume assessment during IC. Methods: We retrospectively assessed the tumor volume of 58 pts with LAHNSCC included in a prospective phase II trial which evaluated the safety of a non–5-fluorouracil-based IC (paclitaxel; cisplatin) followed by chemoradiotherapy (cisplatin; 70Gy/35fx) during 2009-2012. The volume of primary tumor (PrimV), all suspicious lymph nodes (LNV) and their sum (SumV) were determined on tomography before (CT1) and after (CT2) IC using a radiotherapy treatment planning system and the ratio of volumetric change was calculated for each variable (PrimV%, LNV% and SumV%). Results: The median follow-up time, the progression free survival (PFS) and the overall survival (OS) was 78,1, 19,3 and 22,5 months, respectively. Fifty-four pts were men, mean age 55,3±8,3y. Most had oropharynx (53%) and stage IV (72%) cancer. The median volume (cm3) was PrimV1= 25,5, LNV1= 7,5, SumV1= 40,7, PrimV2= 10,9, LNV2= 3,0, SumV2= 18,8 and median ratio of change (%) was PrimV% = 55, LNV% = 51 and SumV% = 54. Volume wa s associated with resectability (PrimV1, AUC ROC curve = 0,66, p = 0,04; LNV1, AUC = 0,85, p < 0,001; SumV1, AUC = 0,86, p < 0,001). Pts with SumV% reduction > 35% had better PFS (median 84,0 vs 10,1 months, 3y 52% vs 29%; HR = 0,39, p = 0,01) and OS (median 45,5 vs 17,0 months, 48% vs 21%; HR = 0,49, p = 0,04). On univariate analysis the PFS was correlated with T (p = 0,004), N (p = 0,01), stage (p = 0,03), primary site (p = 0,01), resectability (HR = 0,32, p = 0,001), PrimV1 (p = 0,002), SumV1 (p = 0,001), PrimV2 (p = 0,02), LNV2 (p = 0,04), SumV2 (p = 0,004), PrimV% (p = 0,04), LNV% (p = 0,003) and SumV% (p = 0,04) and OS was associated with T (p = 0,04), N (p = 0,02), stage (p = 0,04), primary site (p = 0,01), resectability (HR = 0,29, p < 0,001) PrimV1 (p = 0,003), LNV1 (p = 0,002) and SumV1 (p < 0,001). Conclusions: Tumor volume and the volumetric response during IC were associated with prognosis in LAHNSCC in the present study. Clinical trial information: NCT00959387.

scholarly journals Dose Painting with a Variable Collimator for the Small Animal Radiation Research Platform (SARRP)

2014 ◽  
Author(s):  
Nathan Cho ◽  
John Wong ◽  
Peter Kazanzides
Keyword(s):  
Radiation Treatment ◽  
Small Animal ◽  
Planning System ◽  
Treatment Planning System ◽  
Target Area ◽  
Dose Painting ◽  
Target Region ◽  
Research Platform ◽  
Minimum Number ◽  
Radiation Research

The goal of radiation treatment is to irradiate cancer cells (i.e., a target region) without destroying adjacent healthy tissue. Thus, it is advantageous to form the beam so that it best approximates the target, thereby reducing the amount of dose absorbed in critical regions outside the target area. While multi-leaf collimators are common in human clinical systems, small animal radiotherapy systems are typically limited to a set of fixed-size collimators. For these systems, dose painting can be used for conformal dose delivery, but is significantly slower than a multi-leaf collimator. As a compromise solution, a variable rectangular collimator has been developed for the Small Animal Radiation Research Platform (SARRP). This enables more efficient dose painting via the decomposition of a 2D target region into a minimum number of rectangles of variable size, which is the topic of this paper. The proposed method consists of several distinct steps and was implemented on the SARRP Treatment Planning System (TPS).

scholarly journals Multi-criteria optimization for planning volumetric-modulated arc therapy for prostate cancer

PLoS ONE ◽  
2021 ◽  
Vol 16 (9) ◽  
pp. e0257216
Author(s):  
Jongmoo Park ◽  
Jaehyeon Park ◽  
Sean Oh ◽  
Ji Woon Yea ◽  
Jeong Eun Lee ◽  
...  
Keyword(s):  
Prostate Cancer ◽  
Treatment Planning ◽  
Volumetric Modulated Arc Therapy ◽  
Planning System ◽  
Treatment Planning System ◽  
Target Coverage ◽  
Arc Therapy ◽  
Femoral Heads ◽  
Treatment Volume ◽  
Dose Constraints

We aimed to compare the volumetric-modulated arc therapy (VMAT) plans with or without multi-criteria optimization (MCO) on commercial treatment-planning systems (Eclipse, Varian Medical System, Palo Alto, CA, USA) for patients with prostate cancer. We selected 25 plans of patients with prostate cancer who were previously treated on the basis of a VMAT plan. All plans were imported into the Eclipse Treatment Planning System version 15.6, and re-calculation and re-optimization were performed. The MCO plan was then generated. The dosimetric quality of the plans was evaluated using dosimetric parameters and dose indices that account for target coverage and sparing of the organs at risk (OARs). We defined the rectum, bladder, and bilateral femoral heads. The VMAT-MCO plan offers an improvement of gross treatment volume coverage with increased minimal dose and reduced maximal dose. In the planning treatment volume, the Dmean and better gradient, homogeneity, and conformity indexes improved despite the increasing hot and cold spots. When implemented through the MCO plan, a steeper fall off the adjacent OARs in the overlap area was achieved to obtain lower dose parameters. MCO generated better sparing of the rectum and bladder through a tradeoff of the increasing dose to the bilateral femoral heads within the tolerable dose constraints. Compared with re-optimization and re-calculation, respectively, significant dose reductions were observed in the bladder (241 cGy and 254 cGy; p<0.001) and rectum (474 cGy and 604 cGy, p<0.001) with the MCO. Planning evaluation and dosimetric measurements showed that the VMAT-MCO plan using visualized navigation can provide sparing of OAR doses without compromising the target coverage in the same OAR dose constraints.

scholarly journals Consistency Study of Multiparametric Magnetic Resonance and Computed Tomography Targeting in Targeted Radiotherapy for Prostate Cancer

2020 ◽  
Author(s):  
Zhen Xu ◽  
Xiao-Dong Li ◽  
Lu Fu ◽  
Yong-Hua Yu
Keyword(s):  
Prostate Cancer ◽  
Computed Tomography ◽  
Magnetic Resonance ◽  
Organs At Risk ◽  
Target Volume ◽  
Planning System ◽  
Treatment Planning System ◽  
Target Area ◽  
Target Delineation ◽  
Significant Difference

Abstract Background: To compare the difference of location by computed tomography (CT) and multiparametric magnetic resonance imaging (mpMRI) on the target delineation and volume for organs at risk (OARs) among patients with prostate cancer. Methods: T1-weighted imaging (T1WI), T2-weighted imaging (T2WI), and CT were performed among 11 patients who received radiotherapy for prostate cancer at our center between August 2018 and December 2019. The target areas were delineated using the Eclipse system, and the radiotherapy plans were made based on the treatment planning system (TPS) to compare target volume and dose-volume histogram (DVH) relative to rectum and bladder. Results: The clinical target volume (CTV) of T1WI and T2WI decreased by 18.8% (P=0.001) and 22.72% (P=0.003), respectively, compared with CT. The planning target volume (PTV) on T1WI and T2WI were 20.45% (P=0.015) and 22.31% (P= 0.008) smaller than that defined by CT. There was no significant difference in either CTV or PTV between the areas outlined on T1WI and T2WI. The DVH resulting from CT and MRI comparisons showed that the rectum and bladder dose levels were lower with MRI images compared with CT. It should be noted that at the lateral directions, the range of outlining on T2WI sequence were significantly smaller than others. Conclusion: Target planning based on mpMRI (T1WI, T2WI) is more precise than CT, which can significantly reduce the range of the target area and the volume of rectum and bladder exposed to high levels of radiation, improve the fitness and radiographic accuracy of the target area, especially on T2WI.

scholarly journals DELINEATION OF TARGET VOLUME FOR BRAIN TUMORS IN RADIOTHERAPY USING ACTIVE CONTOUR SEGMENTATION AND SIMPSON INTEGRATION

2020 ◽  
Vol 6 (6) ◽  
pp. 137-145
Author(s):  
Walimatul Fitriyah ◽  
Evi Setiawati ◽  
Kusworo Adi
Keyword(s):  
Brain Tumor ◽  
Active Contour ◽  
Target Volume ◽  
Planning System ◽  
Treatment Planning System ◽  
Target Area ◽  
Three Dimension ◽  
Contour Segmentation ◽  
Volume Calculations ◽  
Radio Therapy

This research conducts the delineation process for a brain tumor on the radio therapy. Delineation means the imaging process of target volume that is conducted in the beginning of Treatment Planning System (TPS). Target volume consists of gross tumor volume (GTV), clinical target volume (CTV), planning target volume (PTV), and Organ at Risk (OAR). This research aims to delineate target volume and measure the target volume axial brain tumor. The images that are used are Magnetic Resonance Imaging (MRI) including axial, coronal, and sagittal slice. Evaluation is only done with one patient affected by a brain tumor. Delineation process is performed by the active contour segmentation method and volume calculations using Simpson integration method. The delineation of target volume is conducted by segmenting each slice of images moreover they are reconstructed until the three dimension of visualized target volume is obtained. Having done this process, target area and target volume calculations are conducted. This research results range error rate for target area is 0.0006 to 0.0059 and target volume is 0.0001 to 0.0013

scholarly journals The Influence of SSO on the Optimization Result of Nasopharynx Carcinoma Plan

2021 ◽  
Author(s):  
Xiaolong HUA ◽  
Jianhe YU ◽  
Lu WANG ◽  
Li CHEN ◽  
Yanshu MU ◽  
...  
Keyword(s):  
Organs At Risk ◽  
Planning System ◽  
Treatment Planning System ◽  
Target Area ◽  
Delivery Time ◽  
Parotid Glands ◽  
Similar Dose ◽  
Significant Difference ◽  
Clinical Radiotherapy ◽  
Better Than

Abstract PurposeTo study the influence of Monaco 5.4 treatment planning system (TPS) on the dosimetry of radiotherapy for nasopharynx carcinoma (NPC) under the condition of different segment shape optimization (SSO) times.MethodsFifteen patients with T3-4N0-2M0 stage NPC were enrolled, and each case was designed with SSO of 3, 5, 7 and 10 times respectively. The dose results of the target area and the major organs at risk (OARs) were statistically analyzed by DVH statistics; moreover, the isodose lines of 70Gy, 60Gy and 54Gy were intercepted at the same plane in the transverse, coronal and sagittal views and the segment shapes were compared at the angle of 30°, 120°, 240° and 330° in beam eye view (BEV); In addition, optimization time (OT), delivery time (DT), segments# and monitor unit (MU#) were obtained and analyzed by optimization console; the plans were verified and analyzed by using ArcCheck phantom.ResultsFor target area D2, the results of the SSO7 group and the SSO10 group were similar and both better than those of SSO3 and SSO5 groups, and the D2 results of the SSO3 group were notable higher than those of the other three groups; for the major OARs, the results of the maximum dose of spinal cord, brain stem, and lens and the mean dose and V30 of parotid glands showed the same trend. It showed that SSO7 and SSO10 share similar dose results, too which are notable better than the similar dose results shared by SSO3 and SSO5; in the dose deprogram distribution of 70Gy, 60Gy and 54Gy, partial 70Gy dose spillover occurred in both groups SSO3 and SSO5 and it was more obvious in group SSO3. While there was a no significant dose spillover in group SSO7 and group SSO10; in the sub-field alignment comparison under the same angle, the alignment became more complicated and the sub-fields were smaller as the number of SSO increased; the results of segment#, MU# and plan delivery time between different SSO groups were slightly different, while the plan optimization time changed significantly. The difference between group SSO3 and group SSO10 was more than 500s; the results were compared in ArcCheck, there was no significant difference between the groups.ConclusionsThe user-defined SSO function of Monaco 5.4 TPS effectively balances the relationship between plan design efficiency and plan quality. When SSO is 7, it is better value for efficiency and quality in clinical radiotherapy for NPC.

scholarly journals The Influence of SSO on the Optimization Result of Nasopharynx Carcinoma Plan

2021 ◽  
Author(s):  
Xiaolong HUA ◽  
Jianhe YU ◽  
Lu WANG ◽  
Jiaqi DAI ◽  
Qun REN ◽  
...  
Keyword(s):  
Nasopharyngeal Carcinoma ◽  
Organs At Risk ◽  
Planning System ◽  
Treatment Planning System ◽  
Target Area ◽  
Delivery Time ◽  
Parotid Glands ◽  
Similar Dose ◽  
Significant Difference ◽  
Better Than

Abstract PurposeTo study the influence of Monaco 5.4 treatment planning system (TPS) on the dosimetry of radiotherapy for nasopharynx carcinoma (NPC) under the condition of different segment shape optimization (SSO) times.MethodsFifteen patients with T3-4N0-2M0 stage nasopharyngeal carcinoma were enrolled, and each case was designed with SSO of 3, 5, 7 and 10 times respectively. The dose results of the target area and the major organs at risk (OAR) were statistically analyzed by DVH statistics; moreover, the isodose lines of 70Gy, 60Gy and 54Gy were intercepted at the same plane in the transverse, coronal and sagittal views and the segment shapes were compared at the angle of 30°, 120°, 240° and 330° in beam eye view (BEV); In addition, optimization time (OT), delivery time (DT), segments# and MU# were obtained and analyzed by optimization console; the plans were verified and analyzed by using ArcCheck phantom.ResultsFor target area D2, the results of the SSO7 group and the SSO10 group were similar and both better than those of SSO3 and SSO5 groups, and the D2 results of the SSO3 group were notable higher than those of the other three groups; for the major OARs, the results of the maximum dose of spinal cord, brain stem, and lens and the mean dose and V30 of parotid glands showed the same trend. It showed that SSO7 and SSO10 share similar dose results, too which are notable better than the similar dose results shared by SSO3 and SSO5; in the dose deprogram distribution of 70Gy, 60Gy and 54Gy, partial 70Gy dose spillover occurred in both groups SSO3 and SSO5 and it was more obvious in group SSO3. While there was a no significant dose spillover in group SSO7 and group SSO10; in the sub-field alignment comparison under the same angle, the alignment became more complicated and the sub-fields were smaller as the number of SSO increased; the results of segment#, MU# and plan delivery time between different SSO groups were slightly different, while the plan optimization time changed significantly. The difference between group SSO3 and group SSO10 was more than 500s; the results were compared in ArcCheck, there was no significant difference between the groups.ConclusionsThe user-defined SSO function of Monaco 5.4 TPS effectively balances the relationship between plan design efficiency and plan quality. When SSO is 7, it is better value for efficiency and quality in clinical radiotherapy for nasopharyngeal carcinoma.

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