Evidence map›Paper›PMID 32267535›Full record

ArticleMedical physics2020

Dose escalation in the definite target volume.

W Tyler Watkins, Hamidreza Nourzadeh, Jeffrey V Siebers

Abstract read
In one paragraph

Article in Medical physics, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 1 paper.

0numbers the graph read from it
0cells of the map it votes in
1citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

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Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

1 citing paper in PubMed.

  1. Article
4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

3 authors.

W Tyler WatkinsDepartment of Radiation Oncology, University of Virginia, Charlottesville, VA, 22908, USA.
Hamidreza NourzadehDepartment of Radiation Oncology, University of Virginia, Charlottesville, VA, 22908, USA.
Jeffrey V SiebersDepartment of Radiation Oncology, University of Virginia, Charlottesville, VA, 22908, USA.

Funding

Comprehensive analysis and mitigation of the clinical effects of delineation and geometric uncertainties in conformal radiation therapyR01CA222216 · NCI · UNIVERSITY OF VIRGINIA · PI SIEBERS, JEFFREY VINCENT · 2018 to 2023
$1.6M
Biomedical Innovation FundIvy FoundationNCI NIH HHS R01 CA222216NIH HHS R01CA22221601AUniversity of Virginia
6 · The paper itself

Abstract

purposeTo introduce the definite target volume (DTV) and evaluate dosimetric consequences of boosting dose to this region of high clinical target volume (CTV)- and low organs at risk (OAR)-probability.

methodsThis work defines the DTV via occupancy probability and via contraction of the CTV by margin M less any planning risk volume (PRV) volumes. The equivalence to within varying occupancy probability of the two methods is established for spherical target volumes. We estimate a margin for four radiation treatment sites based on modern images guided radiation therapy-literature utilizing repeat volumetric imaging. Based on margins and patient-specific DTV targets, the ability to dose escalate the DTV including the effects of spatial uncertainty was evaluated. We simulate delivery assuming violation of the underlying spatial uncertainty of 130%.

resultsContracting the planning target volume (PTV) by M and excluding PRV volumes, the DTV ranged from 7.3 to 93.6 cc. In a brain treatment, DTV-Dmax increased to 66.8 Gy (145% of prescription isodose); in advanced lung DTV-Dmax increased to 122.2 Gy (204% of prescription isodose), in a pancreatic case DTV-Dmax was boosted up to 87.3 Gy (173% or prescription isodose), and in retroperitoneal sarcoma to 74.6 Gy (249% of prescription isodose). The high point doses were not associated with increased dose to OARs, even when considering the effects of spatial uncertainty. Simulated delivery at 130% of assumed spatial uncertainties revealed DTV-based planning can result in minor increases in OAR Dmean/Dmax of 2.7 ± 2.1 Gy/1.8 ± 2.2 Gy with duodenum Dmax > 110% of prescription isodose in the pancreatic case. These dose increases were consistent with simulation of clinical, homogenous PTV-dose distributions.

conclusionWe have proposed and tested a method to deliver extremely high doses to subvolumes of target volumes in multiple treatment sites by defining a new target volume, the DTV. Based on simulated delivery, the method does not result in significant increases in dose to OARs if spatial uncertainty can be estimated.

Indexed as

Organs at RiskRadiotherapy Planning, Computer-AssistedHumansRadiometryRadiotherapy DosageUncertaintydose escalationgeometric uncertaintyradiation therapy

Identifiers

PMID32267535
PMCPMC8259326

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.