Publication Date


Document Type


Committee Members

Brent Foy (Committee Chair), Paul Hanny (Committee Member), David Smith (Committee Member)

Degree Name

Master of Science (MS)


The treatment outcomes of many forms of breast cancer have become very favorable. The usual standard of successful treatment of five years without a recurrence is not adequate any longer for breast cancer. Many patients live well beyond this time interval only to have a second malignancy develop in the contralateral breast ten or twenty years later. Boice et al (1992) found that there was a correlation between the amount of dose to the contralateral breast and the likelihood of a secondary malignancy forming.

The normal practice today is to use multi-leaf collimators (MLC) to modulate the photon beam in radiation therapy. Due to the limited use of physical compensators, very little data has been presented as to their effectiveness in reducing dose to the contralateral breast. This study will use a Varian 2100 C/D linear accelerator to irradiate a Rando phantom with simulated breast material using both the traditional method and the compensator method. The dose to the contralateral breast will be measured using MOSFETs at various depths in the tissue.

The results suggest that the compensators do not reduce the dose to the contralateral breast as effectively as the MLC method. There were a few instances for specific cases where the compensator performed better and these cases require further study for verification and clarity.

Page Count


Department or Program

Department of Physics

Year Degree Awarded


Included in

Physics Commons