Dosimetric and radiobiological comparison of external beam radiotherapy using simultaneous integrated boost technique for esophageal cancer in different location.

2019 ◽  
Vol 37 (15_suppl) ◽  
pp. e15505-e15505
Author(s):  
Lu Wang ◽  
Jinming Yu
Keyword(s):  
Esophageal Cancer ◽  
External Beam Radiotherapy ◽  
Intensity Modulated Radiotherapy ◽  
Target Volume ◽  
Simultaneous Integrated Boost ◽  
Conformity Index ◽  
Tumor Control ◽  
Tumor Control Probability ◽  
Integrated Boost ◽  
Treatment Plans

e15505 Background: Based on dosimetry and radiobiology to compare treatment plans for esophageal cancer (EC) in different location using intensity modulated radiotherapy (IMRT), volumetric modulated arc radiotherapy (VMAT) and helical tomotherapy(HT) with simultaneous integrated boost (SIB) technique. Methods: A total of 20 patients including 5 cases respectively located in the cervix, upper, middle and lower thorax were generated for IMRT, VMAT and HT plans. The dose volume histogram statistics, conformity index (CI), homogeneity index (HI), tumor control probability (TCP) and normal tissues control probability (NTCP) were analyzed to evaluate treatment plans. Results: HT showed significantly improvement over IMRT and VMAT in terms of CI(0.93±0.03), HI(0.07±0.03) and TCP(88.08±0.82%) in cervical EC(p<0.05). IMRT greatly developed TCP(88.29±1.79%;85.11±0.79%), and offered superior CIs (0.87±0.04;0.90±0.01) and HIs(0.10±0.01; 0.06±0.01) compared with VMAT and HT in upper and middle thoracic EC(p<0.05). Meanwhile, the V30(33.30±6.49%), mean dose (2559.00±219.64cGy) and NTCP(0.50±0.61%) of heart for IMRT were significantly reduced than other two techniques in middle thoracic EC. Patients with lower thoracic EC yielded the similar CIs and HIs(all p>0.05) for the 3 techniques, but VMAT showed the lowest NTCP of lungs (0.01±0.01%) with improved TCP (84.84±1.13%). Conclusions: HT was a good option with little lung and heart involvement as it achieved superior dose conformality and uniformity. IMRT was a perfect strategy with large thoracic involvement. It significantly improved tumor local control and reduced heart dose and complications with acceptable dose to lungs. VMAT was preferred with a smaller target volume but surrounded by more heart and less lungs. Individually choosing optimal technique for EC in different location will be warranted.

Challenges and Differences in External Radiation Therapy for Retinoblastoma: From Standard Techniques to New Developments

2015 ◽  
Vol 103 (5) ◽  
pp. 438-442
Author(s):  
Ayşe Hiçsönmez ◽  
Yıldız Güney ◽  
Ayşen Dizman ◽  
Bahar Dirican ◽  
Yakup Arslan ◽  
...  
Keyword(s):  
Bone Growth ◽  
External Beam Radiotherapy ◽  
Intensity Modulated Radiotherapy ◽  
Target Volume ◽  
Dose Volume Histograms ◽  
Normal Tissues ◽  
Dose Volume ◽  
Significant Difference ◽  
Treatment Plans ◽  
External Radiation Therapy

Aims The purpose of this study is to calculate the treatment plans and to compare the dose distributions and dose-volume histograms (DVH) for 6 external radiotherapy techniques for the treatment of retinoblastoma as well as intensity-modulated radiotherapy (IMRT) and fractionated stereotactic radiotherapy (Cyberknife). Methods Treatment plans were developed using 6 techniques, including an en face electron technique (ET), an anterior and lateral wedge photon technique (LFT), a 3D conformal (6 fields) technique (CRT), an inverse plan IMRT, tomotherapy, and conventional focal stereotactic external beam radiotherapy with Cyberknife (SBRT). Dose volume analyses were carried out for each technique. Results All techniques except electron provided similar target coverage. When comparing conformal plan with IMRT and SBRT, there was no significant difference in planning target volume dose distribution. The mean volume of ipsilateral bony orbit received more than 20 Gy, a suggested threshold for bone growth inhibition. The V20 Gy was 73% for the ET, 57% for the LFT, 87% for the CRT, 65% for the IMRT, 66% for the tomotherapy, and 2.7% for the SBRT. Conclusions This work supports the potential use of IMRT and SBRT to spare normal tissues in these patients.

scholarly journals Simultaneous integrated boost concepts in definitive radiation therapy for esophageal cancer: outcomes and toxicity

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
J. Ristau ◽  
M. Thiel ◽  
S. Katayama ◽  
I. Schlampp ◽  
K. Lang ◽  
...  
Keyword(s):  
Esophageal Cancer ◽  
Radiation Therapy ◽  
Retrospective Analysis ◽  
Dose Escalation ◽  
Cancer Survival ◽  
Intensity Modulated Radiotherapy ◽  
Progression Free Survival ◽  
Distant Metastases ◽  
Simultaneous Integrated Boost ◽  
Integrated Boost

Abstract Background Radiation therapy and chemoradiation therapy play a major role in the definitive management of esophageal cancer. Survival in esophageal cancer patients is still relatively poor, mostly due to high rates of local recurrence and distant metastases. It is hypothesized that dose escalation in radiotherapy could improve outcomes. Therefore, this retrospective analysis aimed to investigate the outcomes and toxicity in patients treated with local dose escalation by means of using simultaneous integrated boost concepts. Methods Between 2012 and 2018, 101 patients with esophageal carcinoma were analyzed in this monocentric, retrospective study. All patients received definitive chemoradiation or radiation therapy alone as intensity modulated radiotherapy. The prescribed dose was 50.4 Gy in 28 fractions to the primary tumor and the elective lymph nodes as well as a simultaneous integrated boost (SIB) with 58.8 Gy to macroscopic tumor and lymph node metastases. Endpoints were overall survival (OS), progression free survival (PFS), local control rate (LCR) and toxicity. Results 60 patients (59.4%) received chemoradiation, 41 patients (40.6%) radiotherapy alone. The median follow up was 17 months (range 0–75 months). OS, PFS and LCR were at 63.9%, 53.9% and 59.9% after 1 year and 37.6%, 34.5% and 36.1%, respectively after 3 years. 16 patients (15.8%) in total developed a locoregional recurrence within the field of radiation. In 48 patients (47.5%) at least one grade III° (CTCAE) toxicity was documented during radiotherapy, mostly dysphagia (36 pat., 75%). One patient suffered from a grade IV° pneumonia. Conclusion This retrospective analysis demonstrates that a SIB concept in definitive (chemo)radiation therapy is safe and feasible, showing acceptable outcomes in this patient cohort. Considering that this cohort mainly consists of elderly patients not eligible for chemotherapy in many cases, we emphasize the aspect of SIB radiation therapy as potential partial compensation for omitted simultaneous chemotherapy. Prospective studies are needed for validation.

Dosimetric comparison between intensity-modulated radiotherapy and volumetric-modulated arc therapy in hippocampus sparing in brain metastasis treated by whole-brain irradiation and simultaneous integrated boost

2019 ◽  
Vol 19 (1) ◽  
pp. 45-51 ◽  
Author(s):  
Ehab Saad ◽  
Khaled Elshahat ◽  
Hussein Metwally
Keyword(s):  
Brain Metastasis ◽  
Organs At Risk ◽  
Volumetric Modulated Arc Therapy ◽  
Intensity Modulated Radiotherapy ◽  
Simultaneous Integrated Boost ◽  
Conformity Index ◽  
Whole Brain ◽  
Intensity Modulated ◽  
Arc Therapy ◽  
Integrated Boost

AbstractBackground:While treating brain metastasis with whole-brain radiotherapy incorporating a simultaneous integrated boost (WBRT-SIB), the risk of hippocampus injury is high. The aim of this study is to compare dosimetrically between intensity-modulated radiotherapy (IMRT) and volumetric-modulated arc therapy (VMAT) in sparing of hippocampus and organs at risk (OARs) and planning target volume (PTV) coverage.Methods:In total, 16 patients presenting with more than one brain metastases were previously treated and then retrospectively planned using VMAT and IMRT techniques. For each patient, a dual-arc VMAT and another IMRT (five beams) plans were created. For both techniques, 30 Gy in 10 fractions was prescribed to the whole brain (WB) minus the hippocampi and 45 Gy in 10 fractions to the tumour with 0·5 cm margin. Dose–volume histogram (DVH), conformity index (CI) and homogeneity index (HI) of PTV, hippocampus mean and maximum dose and other OARs for both techniques were calculated and compared.Results:A statistically significant advantage was found in WB-PTV CI and HI with VMAT, compared to IMRT. There were lower hippocampus mean and maximum doses in VMAT than IMRT. The maximum hippocampus dose ranged between 15·5 and 19·2 Gy and between 18·4 and 20·6 Gy in VMAT and IMRT, respectively. The mean dose of the hippocampus ranged between 11·5 and 17·7 Gy and between 13·2 and 18·3 Gy in VMAT and IMRT, respectively.Conclusion:Using WBRT-SIB technique, VMAT showed better PTV coverage with less mean and maximum doses to the hippocampus than IMRT. Clinical randomised studies are needed to confirm safety and clinical benefit of WBRT-SIB.

scholarly journals Differential Dose Distribution in Transition from 3-D CRT to IMRT Treatment Plans for Glioblastoma Multiforme' at Stage III or IV: A Clinical Study of a Brain Tumor

2018 ◽  
Vol 19 (1) ◽  
pp. 64
Author(s):  
Sadiq R Malik ◽  
Shohel Reza ◽  
MM Shakhawat Hossain
Keyword(s):  
Radiation Therapy ◽  
Dose Distribution ◽  
Selection Process ◽  
Organs At Risk ◽  
Treatment Plan ◽  
Target Volume ◽  
Conformity Index ◽  
Tumor Control ◽  
Treatment Plans

<p><span>Advancement in Cancer Therapy Technology (CTT) due to Software, Hardware and precise delivery of radiation dose has enhanced the quality of life of cancer patients. This report aims at the application of 3-D CRT (Three Dimensional Conformal Radiation Therapy) and IMRT (Intensity Modulated Radiation Therapy) for a quality of treatment. Other anatomical sites viz. Prostate, Lung, etc. may also be treated provided a better tool is applied for target delineation for which FUSION of CT and MRI images are used to ascertain differences in tissue density. This Fusion image of 3 mm slices offer accurate contouring of the tumor. The oncologist and/or physicist perform delineation of (I) GTV (Gross Tumor Volume), (II) CTV (Clinical Target Volume), (III) PTV (Planning Target Volume), (IV) TV (Treated Volume) and (V) OARs (Organs at Risk). This is done to secure conformal dose distribution and justify the clinical objectives of Tumor Control Probability (TCP) by reducing the normal tissue complication probability (NTCP). <span> </span><span> </span>The implication of this study outlines the fundamental goal of effective treatment procedures by comparing treatment plans of 3-D CRT and IMRT. Tolerance levels of dose to different organs are optimized by the analysis of random and systemic geometrical deviations, margin on target volumes, conformity index (CI), patient selection process and, of course, the shape and stage of target. The comparative parameters of treatment plans are segmented and tabulated to implicate the application of necessary tools to decide on a treatment plan for similar patients.</span></p><p><span>Bangladesh J. Nuclear Med. 19(1): 64-67, January 2016</span></p>

scholarly journals Dosimetric and Radiobiological Comparison of Five Techniques for Postmastectomy Radiotherapy with Simultaneous Integrated Boost

2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
Du Tang ◽  
Zhan Liang ◽  
Fada Guan ◽  
Zhen Yang
Keyword(s):  
Breast Cancer ◽  
Organs At Risk ◽  
Intensity Modulated Radiotherapy ◽  
Normal Tissue Complication Probability ◽  
Simultaneous Integrated Boost ◽  
Conformity Index ◽  
Postmastectomy Radiotherapy ◽  
Integrated Boost ◽  
Similar Good ◽  
Delivery Efficiency

Purpose. To compare five techniques for the postmastectomy radiotherapy (PMRT) with simultaneous integrated boost (SIB). Materials and Methods. Twenty patients with left-sided breast cancer were retrospectively selected. Five treatment plans were created for each patient: TomoDirect (TD), unblocked helical TomoTherapy (unb-HT), blocked HT (b-HT), hybrid intensity-modulated radiotherapy (hy-IMRT), and fixed-field IMRT (ff-IMRT). A dose of 50.4 Gy in 28 fractions to PTVtotal and 60.2 Gy in 28 fractions to PTVboost were prescribed. The dosimetric parameters for targets and organs at risk (OARs), the normal tissue complication probability (NTCP), the second cancer complication probability (SCCP) for OARs, and the treatment efficiency were assessed and compared. Results. TD plans and hy-IMRT plans had similar good dose coverage and homogeneity for both PTVboost and PTVtotal and superior dose sparing for the lungs and heart. The ff-IMRT plans had similar dosimetric results for the target volumes compared with the TD and hy-IMRT plans, but gave a relatively higher NTCP and SCCP for the lungs. The unb-HT plans exhibited the highest OAR mean dose, highest NTCP for the lungs (0.97±1.25‰) and heart (4.58±3.62%), and highest SCCP for the lungs (3.57±0.05%) and contralateral breast (2.75±0.29%) among all techniques. The b-HT plans significantly outperformed unb-HT plans with respect to the sparing of the lungs and heart. This technique also showed the best conformity index (0.73±0.08) for PTVboost and the optimal NTCP for the lungs (0.03±0.03‰) and heart (0.61±0.73%). Concerning the delivery efficiency, the hy-IMRT and ff-IMRT achieved much higher delivery efficiency compared with TomoTherapy plans. Conclusion. Of the five techniques studied, TD and hy-IMRT are considered the preferable options for PMRT with SIB for left-sided breast cancer treatment and can be routinely applied in clinical practice.

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