Abstract:
:The management of a pregnant patient in radiation oncology is an infrequent event requiring careful consideration by both the physician and physicist. The aim of this manuscript was to highlight treatment planning techniques and detail measurements of fetal dose for a pregnant patient recently requiring treatment for a brain cancer. A 27-year-old woman was treated during gestational weeks 19-25 for a resected grade 3 astrocytoma to 50.4 Gy in 28 fractions, followed by an additional 9 Gy boost in five fractions. Four potential plans were developed for the patient: a 6 MV 3D-conformal treatment plan with enhanced dynamic wedges, a 6 MV step-and-shoot (SnS) intensity-modulated radiation therapy (IMRT) plan, an unflattened 6 MV SnS IMRT plan, and an Accuray TomoTherapy HDA helical IMRT treatment plan. All treatment plans used strategies to reduce peripheral dose. Fetal dose was estimated for each treatment plan using available literature references, and measurements were made using thermoluminescent dosimeters (TLDs) and an ionization chamber with an anthropomorphic phantom. TLD measurements from a full-course radiation delivery ranged from 1.0 to 1.6 cGy for the 3D-conformal treatment plan, from 1.0 to 1.5 cGy for the 6 MV SnS IMRT plan, from 0.6 to 1.0 cGy for the unflattened 6 MV SnS IMRT plan, and from 1.9 to 2.6 cGy for the TomoTherapy treatment plan. The unflattened 6 MV SnS IMRT treatment plan was selected for treatment for this particular patient, though the fetal doses from all treatment plans were deemed acceptable. The cumulative dose to the patient's unshielded fetus is estimated to be 1.0 cGy at most. The planning technique and distance between the treatment target and fetus both contributed to this relatively low fetal dose. Relevant treatment planning strategies and treatment delivery considerations are discussed to aid radiation oncologists and medical physicists in the management of pregnant patients.
journal_name
J Appl Clin Med Physjournal_title
Journal of applied clinical medical physicsauthors
Labby ZE,Barraclough B,Bayliss RA,Besemer AE,Dunkerley DAP,Howard SPdoi
10.1002/acm2.12262subject
Has Abstractpub_date
2018-09-01 00:00:00pages
368-374issue
5issn
1526-9914journal_volume
19pub_type
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journal_title:Journal of applied clinical medical physics
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journal_title:Journal of applied clinical medical physics
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更新日期:2018-01-01 00:00:00
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更新日期:2014-01-08 00:00:00
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journal_title:Journal of applied clinical medical physics
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更新日期:2017-01-01 00:00:00
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journal_title:Journal of applied clinical medical physics
pub_type: 杂志文章
doi:10.1120/jacmp.v3i2.2580
更新日期:2002-04-01 00:00:00
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journal_title:Journal of applied clinical medical physics
pub_type: 杂志文章
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更新日期:2015-07-08 00:00:00
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更新日期:2000-10-01 00:00:00
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更新日期:2006-01-01 00:00:00
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pub_type: 临床试验,杂志文章
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更新日期:2004-01-01 00:00:00
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更新日期:2010-10-13 00:00:00
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更新日期:2018-05-01 00:00:00
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更新日期:2016-11-08 00:00:00