Assessment of female fertility and carcinogenesis after iodine-131 therapy for differentiated thyroid carcinoma

Abstract

The aim of this study was to evaluate female fertility, carcinogenic, and genetic effects after treatment with 131I of differentiated thyroid carcinoma.

Methods: A total of 814 females of child-bearing age were studied. The fertility of 627 females who received 131I therapy was compared to 187 untreated females. Birth histories of the children born from these women were registered. The carcinogenic effect was evaluated by comparing the incidence of tumors in 730 patients treated with 131I with an internal control group, as well as with local population incidence.

Results: There was no significant difference in the fertility rate, birth weight and prematurity between the two groups. Only one case of a ventricular septal defect was observed in a child born to a women treated with 131I. The overall standardized incidence ratio (SIR) of second tumors was 1.19 (95% CI: 0.76-1.77) in patients treated with 131I. An elevated SIR was registered for salivary gland tumors and melanoma. No case of leukemia was registered.

Conclusion: The risk of long-term effects of 131I treatment of differentiated thyroid carcinoma is quite low. Iodine-131 may be safely used in treating cases with a high risk of recurrence.