Science and Education Publishing International Journal of Physics 2333-4576 4 3 2016 5 11 A 5 Year Retrospective Study of 131I Therapy for Thyroid Cancer Practice in King Abdulaziz University Hospital 69 73 EN Mawya A. Khafaji Majdi R. ALnowaimi Department of Nuclear engineering, faculty of Engineering Kind Abdulaziz University, Jeddah, Saudi Arabia IJP2016435 10.12691/ijp-4-3-5 2016 1 19 2016 3 15 2016 5 9 Since 1940s, intake of Iodine 131 is a deeprooted postoperative therapy for malignant thyroid. However, clinical practice does differ significantly between hospitals. This paper presents a retrospective study of a clinical practice for patients diagnosed with thyroid cancer at King Abdulaziz University Hospital (KAUH). The aim of this study was to benchmark KAUH practice patterns against international guidelines. A total of 100 patients with thyroid cancer were included, 70% females and 30% males with median age of 42.5 and 43.5 years respectively. Cases were patients, diagnosed with thyroid cancer and treated with radioactive iodine at KAUH in Saudi Arabia between 2005 and 2011. Some additional patient's data were excluded from the study because of missing information or lost to follow-up. Medical records included patient's gender, age, clinical diagnoses, iodine dose, and the recurrence. Where, thirty-three percent (33%) of the patients had papillary carcinoma, (3%) had follicular carcinoma and (1%) had Hurtle cell tumors. All patients had their total/partial thyroidectomy at KAUH. Dose administered ranged from (50 to 300) mCi with the 61% receiving a dose of 100mCi. A statistical test, Chisquare test, were used to allow us to test for deviations of observed frequencies from expected frequencies. The medical record showed that 3% of the patient had died and 4% had a recurrence that was successfully treated by the time of the study. Moreover, the 5-year survival rates for patients with thyroid cancers was 93%. The thyroid cancer incidence and the I-131 practice in KAUH is consistent with international data and standards.