title: Investigation of conformal and intensity-modulated radiation therapy techniques to determine the absorbed fetal dose in pregnant patients with breast cancer.
abstract: The aim of this research was to investigate the fetal doses of pregnant patients undergoing conformal radiotherapy or intensity-modulated radiation therapy (IMRT) for breast cancers. An Alderson Rando phantom was chosen to simulate a pregnant patient with breast cancer who is receiving radiation therapy. This phantom was irradiated using the Varian Clinac DBX 600 system (Varian Medical System, Palo Alto, CA) linear accelerator, according to the standard treatment plans of both three-dimensional conformal radiation therapy (3-D CRT) and IMRT techniques. Thermoluminescent dosimeters were used to measure the irradiated phantom׳s virtually designated uterus area. Thermoluminescent dosimeter measurements (in the phantom) revealed that the mean cumulative fetal dose for 3-D CRT is 1.39cGy and for IMRT it is 8.48cGy, for a pregnant breast cancer woman who received radiation treatment of 50Gy. The fetal dose was confirmed to increase by 70% for 3-D CRT and 40% for IMRT, if it is closer to the irradiated field by 5cm. The mean fetal dose from 3-D CRT is 1.39cGy and IMRT is 8.48cGy, consistent with theoretic calculations. The IMRT technique causes the fetal dose to be 5 times more than that of 3-D CRT. Theoretic knowledge concerning the increase in the peripheral doses as the measurements approached the beam was also practically proven.
authors.affiliation: Division of Basic Oncology, Institute of Medical Sciences, Istanbul University, Istanbul, Turkey. Electronic address: akinogretici@gmail.com.
authors.forename: Akın
authors.initials: A
authors.lastname: Öğretici
authors.affiliation: Division of Basic Oncology, Institute of Medical Sciences, Istanbul University, Istanbul, Turkey.
authors.forename: Uğur
authors.initials: U
authors.lastname: Akbaş
authors.affiliation: Division of Basic Oncology, Institute of Medical Sciences, Istanbul University, Istanbul, Turkey.
authors.forename: Canan
authors.initials: C
authors.lastname: Köksal
authors.affiliation: Division of Basic Oncology, Institute of Medical Sciences, Istanbul University, Istanbul, Turkey.
authors.forename: Hatice
authors.initials: H
authors.lastname: Bilge
mesh_terms: D001943:Breast Neoplasms / Q000532:radiotherapy*; D005260:Female; D005333:Fetus / Q000528:radiation effects*; D006801:Humans; D019047:Phantoms, Imaging; D011247:Pregnancy; D011829:Radiation Dosage; D011880:Radiotherapy Planning, Computer-Assisted; D020266:Radiotherapy, Conformal / Q000379:methods*; D050397:Radiotherapy, Intensity-Modulated / Q000379:methods*; D013819:Thermoluminescent Dosimetry
keywords: 3-D CRT; Breast cancer; Fetal dose; IMRT; Pregnancy; TLD