Aims and objectives
The purpose of the present study was to estimate the fetal dose resulting from radiotherapy for common malignancies presented during pregnancy.
Methods and materials
Pregnancy simulation An adult anthropomorphic Rando phantom (Alderson Research Labs,
CA) made of tissue-equivalent material was used.
The phantom consists of 36 numbered 2.5-cm-thick transverse sections.
It can simulate pregnant woman at the 1 st trimester of gestation.
The Rando phantom was modified to represent the geometry of a pregnant woman at the 2 nd and 3 rd trimester of gestation.
The Rando slices 25-31 and 22-31 were replaced with 7 and 10 Lucite slices 2.5-cm-thick,
The fetaldose from radiotherapy for all examined malignancies at the 1 st trimester of gestation was below the well-established threshold of 10 cGy  (Fig 1).
The radiation dose from lymphoma irradiation at the 2 nd trimester of gestation varied from 5.6- 22.4 cGy depending upon the distance between the fetal level and the field edge (Fig 2).
The corresponding dose range in late pregnancy was 5.6-57.9 cGy (Fig 3).
The radiation dose from treatment of neck,
breast and lung...
The fetal dose from radiotherapy for common malignancies presented in pregnancy may exceed the threshold of 10 cGy depending upon the site of treatment and the gestational age.
The presented data are useful for patient management whenever difficult decisions about fetal shielding or pregnancy termination should be taken.
International Commission on Radiological Protection (2000).
Pregnancy and Medical Radiation,
ICRP Publication 84,
Oxford and New York