Abstract
We examined the fetal dose from irradiation of glioblastoma during pregnancy using intensity modulated radiation therapy (IMRT), and describe fetal dose minimization using mobile shielding devices. A case report is described of a pregnant woman with glioblastoma who was treated during the third trimester of gestation with 60 Gy of radiation delivered via a 6 MV photon IMRT plan. Fetal dose without shielding was estimated using an anthropomorphic phantom with ion chamber and diode measurements. Clinical fetal dose with shielding was determined with optically stimulated luminescent dosimeters and ion chamber. Clinical target volume (CTV) and planning target volume (PTV) coverage was 100 and 98 % receiving 95 % of the prescription dose, respectively. Normal tissue tolerances were kept below quantitative analysis of normal tissue effects in the clinic (QUANTEC) recommendations. Without shielding, anthropomorphic phantom measurements showed a cumulative fetal dose of 0.024 Gy. In vivo measurements with shielding in place demonstrated a cumulative fetal dose of 0.016 Gy. The fetal dose estimated without shielding was 0.04 % and with shielding was 0.026 % of the target dose. In vivo estimation of dose equivalent received by the fetus was 24.21 mSv. Using modern techniques, brain irradiation can be delivered to pregnant patients in the third trimester with very low measured doses to the fetus, without compromising target coverage or normal tissue dose constraints. Fetal dose can further be reduced with the use of shielding devices, in keeping with the principle of as low as reasonably achievable.
Similar content being viewed by others
References
Andersen AP (1978) Postoperative irradiation of glioblastomas: results in a randomized series. Acta Radiol Oncol Radiat Phys Biol 17(6):475–484
Kristiansen K et al (1981) Combined modality therapy of operated astrocytomas grade III and IV. Confirmation of the value of postoperative irradiation and lack of potentiation of bleomycin on survival time: a prospective multicenter trial of the Scandinavian Glioblastoma Study Group. Cancer 47(4):649–652
Sandberg-Wollheim M et al (1991) A randomized study of chemotherapy with procarbazine, vincristine, and lomustine with and without radiation therapy for astrocytoma grades 3 and/or 4. Cancer 68(1):22–29
Shapiro WR, Young DF (1976) Treatment of malignant glioma: a controlled study of chemotherapy and irradiation. Arch Neurol 33(7):494–500
Walker MD et al (1978) Evaluation of BCNU and/or radiotherapy in the treatment of anaplastic gliomas: a cooperative clinical trial. J Neurosurg 49(3):333–343
Walker MD et al (1980) Randomized comparisons of radiotherapy and nitrosoureas for the treatment of malignant glioma after surgery. N Engl J Med 303(23):1323–1329
Jeswani S et al (2013) Comparison of survival between cerebellar and supratentorial glioblastoma patients: surveillance, epidemiology, and end results (SEER) analysis. Neurosurgery 73(2):240–246
Blumenthal DT et al (2008) Management of malignant gliomas during pregnancy: a case series. Cancer 113(12):3349–3354
McGrane J, Bedford T, Kelly S (2012) Successful pregnancy and delivery after concomitant temozolomide and radiotherapy treatment of glioblastoma multiforme. Clin Oncol (R Coll Radiol) 24(4):311
Stovall M et al (1995) Fetal dose from radiotherapy with photon beams: report of AAPM Radiation Therapy Committee Task Group No. 36. Med Phys 22(1):63–82
Brent RL (1983) The effects of embryonic and fetal exposure to X-ray, microwaves, and ultrasound. Clin Obstet Gynecol 26(2):484–510
Sneed PK et al (1995) Fetal dose estimates for radiotherapy of brain tumors during pregnancy. Int J Radiat Oncol Biol Phys 32(3):823–830
Jaffe TA et al (2009) Radiation dose for body CT protocols: variability of scanners at one institution. Am J Roentgenol 193(4):1141–1147
Conflict of interest
The authors declare that they have no relevant conflict of interest.
Funding
None.
Author information
Authors and Affiliations
Corresponding author
Additional information
David P. Horowitz and Tony J. C. Wang have contributed equally to this study.
Rights and permissions
About this article
Cite this article
Horowitz, D.P., Wang, T.J.C., Wuu, CS. et al. Fetal radiation monitoring and dose minimization during intensity modulated radiation therapy for glioblastoma in pregnancy. J Neurooncol 120, 405–409 (2014). https://doi.org/10.1007/s11060-014-1565-4
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11060-014-1565-4