Evaluation Target Volume and Distribution Organ at Risk in Rectal Cancer Using 3D-CRT Technique Based on QUANTEC

Abstract

Background: The 3D-CRT technique in rectal cancer patients is a radiation therapy treatment to destroy cancer cells. The success of radiation therapy depends on the accuracy of the target volume dose and Organ At Risk (OAR). Therefore, when administering the dose, it is necessary to calculate it appropriately using QUANTEC to avoid toxicity. Objective: This study is to describe radiotherapy radiation, measurement of Planning Target Volume (PTV) V95% dose distribution and OAR, as well as a comparative analysis of PTV dose distribution against ICRU and OAR against QUANTEC guidelines. Method: The research used is a quantitative descriptive comparative evaluation. This research was conducted in the Department OF Radiotherapy in Jakarta area from September to November 2023. The research was conducted on 20 rectal cancer patients using the 3D-CRT technique and data analysis was carried out using descriptive statistics. Result: The average dose value received by PTV V95% is 5133 or PTV V95% ≥ 4750. Meanwhile, the average dose received by the OAR bladder and femoral head exceeds QUANTEC criteria. This is because the cancer stage has metastasized, and the number of doses and fractions can also affect the dose received by the OAR.