Variation in accumulated dose of volumetric-modulated arc therapy for pancreatic cancer due to different beam starting phases.

Variation in accumulated dose of volumetric-modulated arc therapy for pancreatic cancer due to different beam starting phases. J Appl Clin Med Phys. 2019 Sep 20;: Authors: Sasaki M, Nakamura M, Mukumoto N, Goto Y, Ishihara Y, Nakata M, Sugimoto N, Mizowaki T Abstract PURPOSE: To assess the effects of different beam starting phases on dosimetric variations in the clinical target volume (CTV) and organs at risk (OARs), and to identify the relationship between plan complexity and the dosimetric impact of interplay effects in volumetric-modulated arc therapy (VMAT) plans for pancreatic cancer. METHODS: Single and double full-arc VMAT plans were generated for 11 patients. A dose of 50.4 Gy in 28 fractions was prescribed to cover 50% of the planning target volume. Patient-specific Digital Imaging and Communications in Medicine-Radiation Therapy plan files were divided into 10 files based on the respiratory phases in four-dimensional computed tomography (4DCT) simulations. The phase-divided VMAT plans were calculated in consideration of the beam starting phase for each arc and were then combined in the mid-ventilation phase of 4DCT (4D plans). The dose-volumetric parameters were compared with the calculated dose distributions without consideration of the interplay effects (3D plans). Additionally, relationships among plan parameters such as modulation complexity scores, monitor units (MUs), and dose-volumetric parameters were evaluated. RESULTS: ...
Source: Journal of Applied Clinical Medical Physics - Category: Physics Authors: Tags: J Appl Clin Med Phys Source Type: research

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ConclusionsThis study demonstrates that intra-fraction targeting errors can be within 2mm while inter-fraction shifts from free-breathing spine to ABC breath-hold target can be as high as 8mm. Values that deviate significantly would need further investigation to rule out factors such as local progression, bowel gas or fiducial shift prior to treatment.
Source: Practical Radiation Oncology - Category: Cancer & Oncology Source Type: research
ConclusionSurgical treatment should be considered for pancreatic metastasis from lung cancer if the disease is localized and the patient’s condition is good. Additionally, combined therapy, including surgical resection, may be effective for repeated recurrence.
Source: International Journal of Surgery Case Reports - Category: Surgery Source Type: research
jalmar van Santvoort Bas Groot Koerkamp Olivier R. Busch I. Quintus Molenaar Casper H. van Eijck Marc G. Besselink the Dutch Pancreatic Cancer Group and International Collaborative Group on Locally Advanced Pancreatic Cancer Locally advanced pancreatic cancer (LAPC) has several definitions but essentially is a nonmetastasized pancreatic cancer, in which upfront resection is considered not beneficial due to extensive vascular involvement and consequent high chance of a nonradical resection. The introduction of FOLFIRINOX chemotherapy and gemcitabine-nab-paclitaxel (gem-nab) has had major implications for th...
Source: Cancers - Category: Cancer & Oncology Authors: Tags: Review Source Type: research
CONCLUSION: When mapping of local relapses was evaluated according to the CTVRTOG, the CJ site was identified as a high-risk area of local recurrence but was insufficiently covered within the CTVRTOG. These findings may help construct a target volume for postoperative radiotherapy in DEHC. ADVANCES IN KNOWLEDGE: Mapping local recurrences can aid in defining appropriate target volume for postoperative radiotherapy in DEHC. PMID: 31145644 [PubMed - as supplied by publisher]
Source: The British Journal of Radiology - Category: Radiology Authors: Tags: Br J Radiol Source Type: research
Conclusions The recent, first randomized clinical trial demonstrated overall and progression free survival benefits after SBRT to oligometastatic disease which supports prior retrospective case series (6). The spine is a common site of metastatic bone disease, and as high quality data continue to mature, along with completion of additional randomized clinical trials, it is expected that utility of SBRT to the spine will increase in the future. Spine SBRT is unique due to the requirement of sharp dose falloff to prevent serious neurologic morbidity. With recent advances in radiotherapy planning, robotic patient positionin...
Source: Frontiers in Oncology - Category: Cancer & Oncology Source Type: research
ConclusionHPB surgeons should adopt an aggressive policy to treat patients who have undergone previous major abdominal surgery.
Source: International Journal of Surgery Case Reports - Category: Surgery Source Type: research
Abstract PURPOSE: Stereotactic body radiation therapy is a promising treatment modality for locally advanced pancreatic cancer. To determine the optimal radiation treatment, we compared the plan characteristics of volumetric-modulated arc therapy and intensity-modulated radiation therapy when administered with stereotactic body radiation therapy to treat pancreatic cancer. PATIENTS AND METHODS: Fifteen patients with locally advanced pancreatic cancer were treated by stereotactic body radiation therapy at a dose of 24-32Gy in four fractions with marker-guided gated volumetric-modulated arc therapy. Four dimens...
Source: Cancer Radiotherapie - Category: Cancer & Oncology Authors: Tags: Cancer Radiother Source Type: research
ConclusionAn MRI/CT-based treatment planning for high-precision IGRT using different techniques was established in an orthotopic pancreatic tumor model. Advanced radiation techniques allow considering perfect coverage of GTV and sparing of OARs in the preclinical setting and reflect clinical treatment plans of pancreatic cancer patients.
Source: Strahlentherapie und Onkologie - Category: Cancer & Oncology Source Type: research
ConclusionsFLT-PET improves interobserver concordance in GTV definition. Further studies will focus on verification of these findings, pathologic verification of the FLT-PET signal, and optimization of the FLT-PET signal threshold for autosegmentation.
Source: Practical Radiation Oncology - Category: Cancer & Oncology Source Type: research
ConclusionAn MRI/CT-based treatment planning for high-precision IGRT using different techniques was established in an orthotopic pancreatic tumor model. Advanced radiation techniques allow considering perfect coverage of GTV and sparing of OARs in the preclinical setting and reflect clinical treatment plans of pancreatic cancer patients.
Source: Strahlentherapie und Onkologie - Category: Cancer & Oncology Source Type: research
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