TITLE:
Case Report: Anaplastic Astrocytoma Treated with Postoperative Radiotherapy Using Flattening Filter-Free Volumetric Arc Therapy (FFF-VMAT) during Pregnancy—Acceptable Fetal Dosimetry
AUTHORS:
Tomoyuki Noyama, Wataru Takahashi, Yuki Nozawa, Kanabu Nawa, Hideomi Yamashita, Osamu Abe, Keiichi Nakagawa
KEYWORDS:
Pregnancy, Radiotherapy, Flattening Filter-Free, Volumetric Arc Therapy, An-aplastic Astrocytoma, Fetal Dose
JOURNAL NAME:
Journal of Cancer Therapy,
Vol.11 No.11,
November
26,
2020
ABSTRACT: Background: Postoperative irradiation for brain tumor in pregnant women is a matter
of concern. Aim: We aimed to assess the safety of radiotherapy for brain
tumors in pregnancy. We here report a successful treatment for anaplastic
astrocytoma during pregnancy: surgery + postoperative irradiation. We wish to
emphasize how we devised irradiation procedure to achieve both therapeutic
effectiveness and safety to the fetus/infant. Case Presentation: A
34-year-old pregnant woman suffered with brain anaplastic astrocytoma. Tumor
resection under craniotomy was performed with success. We decided to conduct
postoperative radiotherapy at 25 weeks of gestation to reduce the risk of
recurrence. We used a flattening filter-free volumetric arc therapy (FFF-VMAT)
technique, which can achieve lower out-of-field dose than VMAT with a
flattening filter or helical tomotherapy. We prescribed 60 Gy over 30
fractions. During actual beam delivery, surface and rectal dose to the patient
(mother) were measured. The total fetal dose was estimated at 0.006 - 0.018 Gy,
which is under the threshold set by the ICRP. A male healthy infant was born
vaginally at the 37th week of pregnancy. The patient (mother) and the infant
are healthy at the time of writing. Conclusion: FFF-VMAT is a good
choice for brain tumors during pregnancy.