REPAIR EFFECT ON TUMOR CONTROL PROBABILITY (TCP) CALCULATION USING EQUIVALENT UNIFORM DOSE (EUD) MODEL

• Main Author: Fatimah, Nurul
• Format: Final Project
• Language: Indonesia
• Subjects: Fisika
• Online Access: https://digilib.itb.ac.id/gdl/view/32328
• Institution: Institut Teknologi Bandung

Tumor control probability (TCP) is a tool used for treatment planning evaluation that represents the probability of tumor controlled by radiotherapy treatment. The most dominant biological factor affecting TCP is repair effect which means the ability of cells to repair sublethal damage caused by radiotherapy treatment. In this study, TCP is modified with consideration of repair effect using EUD model based on assumption that clonogenic cells’ surviving fraction on tumor following linear-quadratic model. The modified model is then called as rEUD model. TCP calculation was performed using some EUD models (cEUD, cEUD-LQ, and rEUD) on 7 glioblastoma, brain cancer patients, so that the repair effects on TCP calculation using EUD model can be concluded. TCP calculation using cEUD-LQ model is sensitive to cold spot, so it is not appropriate for patients with relatively big tumor volume. In this research, TCP calculation using rEUD model also performed with fractionation scheme variations (standard fractionation, hipofractionation, and hyperfractionation). Based on the study, it can be concluded that hipofractionation scheme is better than the other schemes, especially on TCP calculation using EUD model with consideration of repair effect. Shorter overall treatment time, less fraction delivery, and higher dose per fraction given to the patient may cause the TCP higher.