Reversal of Radioiodine-Induced Azoospermia in Thyroid Cancer: A Case Report

Introduction:Radioiodine-131 ( ¹³¹I) is a commonly used adjuvant therapy following surgery for differentiated thyroid cancer (DTC). The non-specific radiation damage may affect the male reproductive system, impacting sperm quality. However, reports of azoospermia are rare. Case Presentation: A 26-year-old male patient with papillary thyroid carcinoma underwent cumulative 14.06 GBq ¹³¹I ablation therapy postoperatively. Eight months post-treatment, he was diagnosed with azoospermia due to planned conception. After ruling out congenital factors, ¹³¹I-related iatrogenic injury was considered. Sperm was detected again in a semen analysis 13 months after treatment completion. Subsequently, successful natural conception occurred, and the spouse delivered a healthy infant vaginally. Conclusion: ¹³¹I therapy may induce azoospermia. However, the injury may be reversible. Clinicians should monitor reproductive risks in young patients and conduct follow-up evaluations.