Abstract
The risk of inducing contralateral breast (CLB) cancer in patients undergoing tangential field irradiation for the treatment of breast cancer is a serious concern in radiation oncology. A bilateral breast phantom made of wax attached onto the Alderson Rando phantom was used for studying the CLB dose for techniques using physical wedges, EDWs, IMRT and open fields. The skin dose to the CLB was measured at four different points (3 cm from the medial border of the tangential field (P1), nipple (P3), axilla (P4), midpoint between P3 and P1 (P2)). The highest measured dose occurred at P1 with the 60° physical wedges; it was 15.3 % of the dose at isocentre. Similarly, the dose measured at P3 (nipple) with 60° physical wedges was 1.90 times higher than the dose with 60° EDWs. The dose at P1 for IMRT (7.8%) was almost the same as that for the open field (8.7%). The skin dose measured at the nipple was 2.1 – 10.9 % of the isocentre dose. The highest CLB doses were contributed by medial wedged fields. The dose to the CLB can be reduced by using IMRT or avoiding wedging the medial tangential fields. A set-up error in the longitudinal direction has little impact on the CLB dose. Set-up errors >1 cm in the vertical and lateral directions have significant impact on the CLB dose.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Boice, J.D., Harvey, E.B., Blettner, M., Stovall, M. and Flannery, J.T.Cancer in the contralateral breast after radiotherapy for breast cancer. N. Engl. J. Med. 326:781–785, 1992.
Tercilla, O., Krasin, F. and Lawn-Tsao L.Comparison of contralateral breast doses from 1/2 beam block and isocentric treatment techniques for patients treated with primary breast irradiation with 60 Co. Int. J. Radiat. Oncol. Biol. Phys. 17:205–210, 1989.
Fraass, B.A., Roberson, P.L. and Lichter, A.S.Dose to the contralateral breast due to primary breast irradiation. Int. J. Radiat. Oncol. Biol. Phys. 11:485–497, 1985.
Chuang, C.F., Verhey, L.J. and Xia, P.Investigation of the use of MOSFET for clinical IMRT dosimetric verification. Med. Phys. 29:1109–15, 2002.
Weides, C.D., Mok, E.C., Chang, W.C., Findley, D.O. and Shostak, C.A.Evaluating the dose to the contralateral breast when using a dynamic wedge versus a regular wedge. Med. Dosim. 20:287–293, 1995.
McParland, B.J.The effect of a dynamic wedge in the medial tangential field upon the contralateral breast dose. Int. J. Radiat. Oncol. Biol. Phys. 19:1515–1520, 1990.
Kelly, C.A., Wang, X.Y., Chu, J.C. and Hartsell, W.F.Dose to contralateral breast: a comparison of four primary breast irradiation techniques. Int. J. Radiat. Oncol. Biol. Phys. 34:727–732, 1996.
Epstein, R.J., Kelly. S.A., Cook, M., Bateman, A., Paddick, I., Kam, K.C., Dunn, P., Hanham, I.W., Dale, R.G. and Price, P.M.Active minimisation of radiation scatter during breast radiotherapy: management implications for young patients with good-prognosis primary neoplasms. Radiother. Oncol. 40: 69–74, 1996.
Warlick, W.B., O’Rear, J.H., Earley, L., Moeller, J.H., Gaffney, D.K. and Leavitt, D.D.Dose to the contralateral breast: a comparison of two techniques using the enhanced dynamic wedge versus a standard wedge. Med. Dosim. 2:185–191, 1997.
Chang, S.X., Deschesne, K.M., Cullip, T.J., Parker, S.A. and Earnhart, J.A comparison of different intensity modulation treatment techniques for tangential breast irradiation. Int. J. Radiat. Oncol. Biol. Phys. 45:1305–14, 1999.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Prabhakar, R., Haresh, K.P., Julka, P.K. et al. A study on contralateral breast surface dose for various tangential field techniques and the impact of set-up error on this dose. Australas. Phys. Eng. Sci. Med. 30, 42–45 (2007). https://doi.org/10.1007/BF03178408
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF03178408