Thyroid Cancer Patients Treated with ¹³¹I: Radiation Dose to Relatives After Discharge from the Hospital

Background: Thyroid cancer patients treated with radioiodine are potential source of radiation exposure for other individuals. Thus, we evaluated the radiation dose received by family members of thyroid cancer patients treated with 131I after hospital discharge. Materials and Methods: Seventy-six family members of 56 thyroid cancer patients were included in the study. Thyroid cancer patients were given 3.7 GBq of 131I and remained in a radiation protection ward for 3 days. Radiation protection recommendations were given to patients and relatives. Life conditions were recorded and radiation doses were monitored using a personal dosimeter. Results and Discussion: At discharge, the mean residual activity was 188 MBq. The mean radiation dose delivered to relatives during the 7 days after discharge was low (51.5 μSv) and was similar with either recombinant human thyrotropin (rhTSH) (59 μSv) or withdrawal (50 μSv) (p = 0.37). Conclusion: With our current practice, radiation doses to relatives are low and well below international recommendations.