Perpustakaan Digital ITB

Cervical cancer is the most common cause of women’s mortality in the world. In treating cervical cancer with radiotherapy, IAEA suggested the combination of EBRT as a primary treatment and HDR Brachytherapy as a dosage boost. However, it is still a major problem to treat patients within the recommended time or 8 weeks. The prolongation of the treatment time can cause an increase of failure by 1% per day. To understand the ability of HDR brachytherapy as a monotherapy, DOSXYZnrc was used to simulate the dose distribution of the source inside a voxelized phantom. The dose distribution data were then used as an input to modeled the DVH as a quality indicator and also to calculate 2 radiobiological metrics: TCP and NTCP as a quantity measure of the treatment plan. EUD is a mathematical model used to calculate the value of TCP and NTCP. The radiobiological parameters were evaluated for 10 fractionations of a total dose of 80 Gy. The simulation results in a high TCP value for the target and low NTCP value for the bladder and rectum. The tumor able to achieve TCP of 99.433% and the OARs, bladder and rectum, achieve NTCP of 0% and 0.041%, respectively. Variation of fractionations were calculated, and it was found that rectum had a higher complication probability than bladder when the treatment was done in 7 fractionations or more. From this research, 6 fractionations can produce a good radiobiological result with TCP of 99.882% for the tumor, and NTCP of 0% and 10.787% for the bladder and rectum. This configuration will also increase the chances to finish the treatment less than 8 weeks.