Highlights
- •In vivo dosimetry for lung radiotherapy including SBRT is reviewed.
- •Clinical use (to date) of 3D patient dose estimation methods has been restricted to a small number of academic institutes.
- •Technical challenges that limit the accuracy of these methods are highlighted.
- •Limited data (to date) have been published on in vivo dosimetric methods applied to clinical lung SBRT.
- •This clinical data reveal that delivered dosimetry differs noticeably from the planned dosimetry in up to ∼35% of fractions.
Abstract
SBRT for lung cancer is being rapidly adopted as a treatment option in modern radiotherapy
centres. This treatment is one of the most complex in common clinical use, requiring
significant expertise and resources. It delivers a high dose per fraction (typically
∼6–30 Gy/fraction) over few fractions. The complexity and high dose delivered in only a
few fractions make powerful arguments for the application of in vivo dosimetry methods for these treatments to enhance patient safety. In vivo dosimetry is a group of techniques with a common objective – to estimate the dose
delivered to the patient through a direct measurement of the treatment beam(s). In
particular, methods employing an electronic portal imaging device have been intensely
investigated over the past two decades. Treatment verification using in vivo dosimetry approaches has been shown to identify errors that would have been missed
with other common quality assurance methods. With the addition of in vivo dosimetry to verify treatments, medical physicists and clinicians have a higher degree
of confidence that the dose has been delivered to the patient as intended.
In this review, the technical aspects and challenges of in vivo dosimetry for lung SBRT will be presented, focusing on transit dosimetry applications
using electronic portal imaging devices (EPIDs). Currently available solutions will
be discussed and published clinical experiences, which are very limited to date, will
be highlighted.
Keywords
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Article Info
Publication History
Published online: May 30, 2017
Accepted:
May 22,
2017
Received in revised form:
May 20,
2017
Received:
February 2,
2017
Identification
Copyright
© 2017 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.
