The irregular breathing effect on target volume and coverage for lung stereotactic body radiotherapy.

The irregular breathing effect on target volume and coverage for lung stereotactic body radiotherapy. J Appl Clin Med Phys. 2019 Jun 17;: Authors: Pan CH, Shiau AC, Li KC, Hsu SH, Liang JA Abstract The major challenge in treating a mobile target is obtaining the temporal and spatial information imaging and treatment details. This phantom study quantitatively evaluates the geometric and dosimetric effects of various treatment techniques under different respiratory patterns. The regular motion model was a sinusoidal waveform with a longitudinal range of ±1.5 cm and a period of 4 sec, while irregular motion models were generated by extracting signals from clinical cases. Helical CT for a static target and 4D CT with retrospective sorting were acquired. Phase bin, maximum, and average intensity projection (MIP and AIP) CT datasets were reconstructed. RapidArc and IMRT plans were generated on static and moving target CT datasets with different motion patterns using the phase-based gating and nongating treatment. Dose measurements were performed using EBT3 films. Dose profile and gamma analysis (±3%/1 mm criteria) were used for dose comparisons. For the irregular motions, internal target volume variations between AIP and MIP datasets (AIP/MIP) had slight differences (-6.2% to -7.7%) for gated plans, and larger differences (-12.3% to -15.2%) for nongated plans. Dosimetric measurements showed a high gamma passing rate (>98.5%) for...
Source: Journal of Applied Clinical Medical Physics - Category: Physics Authors: Tags: J Appl Clin Med Phys Source Type: research

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Proton therapy has an important role in the management of head and neck cancer, where the dosimetric characteristics of proton particles are advantageous for treating tumors in complex anatomic areas. In addition to highly targeted dose depositions owing to the Bragg peak and superior lateral dose distribution of proton therapy, the introduction of spot-scanning techniques that allow intensity-modulated proton therapy (IMPT) further improve dose distributions and normal-tissue sparing relative to intensity-modulated (photon) radiation therapy (IMRT), a finding that has been validated in case-matched analyses showing lower ...
Source: Radiotherapy and Oncology - Category: Radiology Authors: Tags: Original Article Source Type: research
Conclusion: VMAT combined with IC/IS BT can result in satisfactory curative outcomes and low incidences of late radiation enterocolitis and cystitis in CC treatment.
Source: Frontiers in Oncology - Category: Cancer & Oncology Source Type: research
Intermediate and long term pulmonary, renal, thyroid, and cataract toxicities are reported in 142 patients after total marrow irradiation (TMI). Mean lung dose of 8 Gy or less is associated with a significant decrease in pulmonary toxicity. IMRT delivery of TMI reduces organ doses and toxicities compared to conventional TBI. Further evaluation of IMRT to deliver TMI, TMLI and organ sparing conformal TBI is warranted.
Source: International Journal of Radiation Oncology * Biology * Physics - Category: Radiology Authors: Source Type: research
Conclusion: The current trial demonstrates that elective IMRT/IGRT of the pelvic nodes with SIB to the prostate for patients with a high-risk of lymphatic spread is safe and shows an excellent clinical outcome without compromising the quality of life. The PLATIN-1 trial delivers eminent baseline data for future studies using modern irradiation techniques.
Source: Frontiers in Oncology - Category: Cancer & Oncology Source Type: research
Introduction Data regarding treatment and survival outcome of patients with adenocarcinoma of the head and neck are limited to case reports and case series. As a consequence of lacking evidence, treatment guidelines do not exist. We aimed to analyze the effect of a bimodal irradiation regime with intensity modulated radiotherapy (IMRT) and carbon ion boost on local control (LC) and survival in adenocarcinoma patients for a large patient collective. Materials and Methods Patient records of eighty consecutive patients treated between 2009 and 2018 were analyzed retrospectively and Kaplan-Meier estimates for LC, overall ...
Source: Frontiers in Oncology - Category: Cancer & Oncology Source Type: research
Abstract PURPOSE: Interplay effects may influence dose distributions to a moving target when using dynamic delivery techniques such as intensity-modulated radiotherapy (IMRT). The aim of this study was to evaluate the impact of organ motion on volumetric and dosimetric parameters in stomach lymphomas treated with IMRT. METHODS: Ten patients who had been treated with IMRT for stomach lymphomas were enrolled. The clinical target volume (CTV) was contoured as the whole stomach. Considering interfractional uncertainty, the internal target volume (ITV) margin was uniformly 1.5 cm to the CTV and then modified ...
Source: Journal of Applied Clinical Medical Physics - Category: Physics Authors: Tags: J Appl Clin Med Phys Source Type: research
Comparing radiation treatment plans by using the same safety margins and dose objectives for all techniques, to ascertain the optimal radiation technique for the stereotactic body radiotherapy (SBRT) of low-ri...
Source: Radiation Oncology - Category: Cancer & Oncology Authors: Tags: Research Source Type: research
Node-positive bladder cancer (NPBC) carries a poor prognosis and has traditionally been treated palliatively. However, surgical series suggest that a subset of NPBC patients can achieve long-term control after cystectomy and lymph node dissection. There is little published data regarding the use of radiotherapy to treat NPBC patients. This is in part due to concerns regarding the toxicity of whole-pelvis radiotherapy using conventional techniques. We hypothesised that, using intensity-modulated radiotherapy (IMRT), the pelvic nodes and bladder could be treated within a radical treatment volume with acceptable toxicity profiles.
Source: Clinical Oncology - Category: Radiology Authors: Tags: Original Article Source Type: research
Conditions:   Esophagus Cancer;   Esophageal Cancer;   Cancer of the Esophagus Interventions:   Radiation: Intensity Modulated Radiation Therapy;   Drug: FOLFOX regimen;   Other: MD Anderson Symptom Inventory (MDASI)-Plus module;   Other: EuroQol (EQ-5D);   Other: SF-12;   Other: MOS Social Support Measure;   Other: CES-D;   Procedure: Blood for ctDNA;   Procedure:  Urine for ctDNA;   Procedure: Blood for SCCA Sponsor: &n...
Source: ClinicalTrials.gov - Category: Research Source Type: clinical trials
Conditions:   Anal Cancer Stage III A;   Anal Cancer Stage III B Intervention:   Drug: Pembrolizumab Sponsor:   Cardiff University Not yet recruiting
Source: ClinicalTrials.gov - Category: Research Source Type: clinical trials
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