Abstract
The risk of cataract following 131I therapy for cancer is unknown. The objective of this study was to evaluate the association between 131I therapy for thyroid cancer and risk of receiving cataract surgery in Taiwan. Methods: This was a nationwide population-based cohort study of patients with thyroid cancer diagnosed during the period 1998–2008. The data were obtained from the Taiwan National Health Insurance Research dataset. The cumulative 131I activity in each patient was calculated. Hazard ratios (HRs) were calculated using a time-dependent survival analysis to estimate the effect of 131I therapy on the risk of receiving cataract surgery. Results: A total of 8221 patients were eligible for the final analysis (mean age 43.2 years, mean follow-up 5.9 years). 69% received 131I with a median cumulative activity of 3.7 GBq. 200 patients received cataract surgery. The adjusted HRs were 0.77 (95%CI = 0.54 to 1.09), 0.92 (95%CI = 0.64 to 1.31) and 1.06 (95%CI = 0.58 to 1.94) for cumulative 131I activity of 0.1-3.6 GBq, 3.7-7.3 GBq and ≥7.4 GBq respectively, compared to a cumulative activity = 0. No trend was noted (P = 0.85). No interaction between 131I activity and age or between 131I activity and sex was noted (all P > 0.05). Conclusion: 131I treatment for thyroid cancer did not increase the risk of receiving cataract surgery up to 10-years following treatment. However, further research with direct lens examination and a longer follow-up period is needed to assess subtle and late adverse effects beyond 10 years.
- Endocrine
- Oncology: Endocrine
- Radiation Safety
- Radionuclide Therapy
- cataract
- iodine radioisotopes
- thyroid neoplasms
- Copyright © 2016 by the Society of Nuclear Medicine and Molecular Imaging, Inc.