The Usefulness of Bolus of Radiation Therapy in Patients with Whole Breast Cancer

Radiation Therapy has been used in the treatment of breast cancer for over 80 years. Technically, it should include a part or all of such areas as chest wall or breast, axilla, internam mammary nodes and supraclavicular nodes. The purpose of this study is treated breast cancer patient to use 6 MV, 10 MV with bolus so that we observe changing of skin dose and evaluate those usefulness. Using woman's phantom, after CT simulate scanning, Through RTP system to make treatment plan, select three any place. And then, we measure that dose rate. After moving the phantom to linac, we put for TLD to three point same as RTP system which we put on the phantom. We exposed 6 MV, 10 MV with bolus and without so that it is measured dose by TLD device(4000 Harshaw). As a reult expose 6 MV,10 MV, it differences 10%, 15% according to bolus and withoout bolus where lateral point from RAO, LPO beam, other one is 20% where the furthest from both beams. To use bolus in the hospital is material to include closely part at skin among tissue of breast cancer. Acquired skin dose from RTP system is uncertainity. So it has to test another system likely TLD or other dosimetry system. Also exposed field of breast cancer is included inhomogeneity such as lung, bone and so on. Therefore it has to be accomplished a dose calculating of inhomogeneity part from treatment plan.