| dc.description.abstract | A critical component of the radiation regimen for treating cancer patients is the precise dose
delivery to the treatment organ while minimizing the dose to the healthy tissue. This study aims
to evaluate in-fi eld organ dose and dose distribution outside the target organs to estimate the
excess lifetime risk of second cancer. The study was carried out with a male Alderson Rando
Phantom. 20 sets of thermoluminescence dosimeters (MTS-100) were used in this study. The
in-fi eld organs absorbed dose was measured by inserting TLDs at diff erent geometrical depths
of the left lung, right lung, and stomach, and for peripheral organs skin dose TLDs were placed
at the surface of the corresponding organs. Target organs were irradiated at 100 cGy and 200
cGy by a 60Co teletherapy unit, and irradiated TLDs were read out by a RE-2000 TLD reader.
For precise dose delivery to the cancerous organs by 60Co teletherapy, the depth dose correction
factor for lung cancer treatment is 0.8667 ± 0.01, and for the stomach is 0.7856 ± 0.017. In the
case of the treatment for the lung and stomach, the closest organs received signifi cant doses
compared to the other distant organs. Thus, the risk of second cancer due to the peripheral dose
is obtained. The stomach is at the highest risk when the lung is the target and the liver is at the
highest risk when the stomach is the targeted organ. | en_US |
