RADOBIOLOGICAL ANALYSIS OF RADIOIODINE ABSORPTION IN THYROID CANCER THERAPY

• Main Author: Puspita Dewi Sudarso, Yuanita
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/54849
• Institution: Institut Teknologi Bandung

Despite radioiodine or I-131 has been used in thyroid cancer treatment as a therapy since a long time ago, there are patients that still doubting the safety and the effectiveness of this therapy. The usage of radioiodine in this therapy made a concern in case of the safety and the effectiveness of the therapy, since patients who undergo this therapy need to be isolated in the hospital which the duration of the isolation will be different for each patient, determined by exposure rate of their body, and because of that health officer will advised patients to do activities so the metabolic process increased. Due to these reasons, this thesis will discuss about the safety and the effectiveness of this therapy and the role of metabolic process in the decreasing of exposure rate. The methods used in this thesis will be different from others; this thesis will be using the body?s exposure rate and urine?s exposure rate of the patients. The exposure rates will be measured in 1-meter distance from the patients for 2, 14, 24, and 38 hours after radioiodine uptake. The body?s exposure rate used to calculate the absorbed dose with MIRD schema, the uptake percentage of the thyroid (to show thyroid?s ability to absorbed radioiodine), absorbed dose rate in the body and calculate the BED and SF from the therapy to know how safe this therapy is and how effective this therapy to ablate the thyroid remnants. The urine?s exposure rate used to calculate washing out percentage that shows how much radioactive waste and its effect to the decreasing of the exposure rates. From this thesis, the uptake percentage of the thyroid is around 8.4-8.7% which still in the range of general uptake percentage for radioiodine in thyroid (5-10%), this value shows that the methods that being used in this thesis can be used to determine how radioiodine being absorbed in the thyroid and its effect for the therapy. The absorbed dose rate in thyroid is 0.0054 rad/jam. It showed that thyroid absorbed dose much more than other organs and it is related to the aim of this therapy, to ablate the thyroid. From the washing out percentage, it can be known that there are differences between male and female patients where male patients have greater percentage, indicating that there is metabolic process that affecting how dose being absorbed and how exposure rate decreased. The BED and SF also can be determined, which the average measured BED is 1.15 Gy and average measured SF is 0.49. While the minimum value of SF to ablate cancer is 0.5, it is indicated that this therapy gives a good result, but patients are advised to retake this therapy in a mean time. This condition also supported by the doctor’s observation to the CT image of the patients, where doctor usually advised their patients to take another treatment. To conclude, the methods that being used in this thesis can be used to determine the safety and effectiveness of the therapy and determined the role of the metabolic process in this therapy. Hopes that this thesis can help the health officers to make sure to their patients that this therapy is safe and by following the instructions they gave; patients can go home faster than normal.