Serum Antimüllerian Hormone is Lower in Patients with Multiple Radioiodine Dose for Treatment of Pediatric Thyroid Cancer.

INTRODUCTION: Treatment of patients with pediatric thyroid cancer (DTC) often involves radioiodine (RAI), which is associated with increased risks of short and long-term adverse outcomes. The impact of RAI treatment on the female reproductive system remains uncertain. Antimüllerian hormone (AMH) is a marker of ovarian reserve and is related to fertility.

OBJECTIVE: To analyze the association between RAI and serum AHM level in women treated with RAI Methods: We evaluated women with pediatric DTC treated with RAI at the age of ≤19 years. Serum AMH was measured Results: The study included 47 patients with a mean age of 25.1 years (12.4-50.8) at AMH measurement and follow-up of 11.8±8.4 years. The mean RAI activity administered was 235mCi (30-1150). Sixteen (34%) received multiple RAI doses (471±215 mCi). Mean AMH level was 2.49ng/mL (0.01-7.81); the level was 1.57 ng/mL (0.01-7.81) after multiple RAI doses and 2.99ng/mL (0.01-6.63) after a single RAI dose (p=0.01). Patients who received a cumulative RAI lower than 200mCi had lower AMH levels (2.23ng/mL, 0.39-7.81) than those who received more (1.0ng/mL, 0.01-6.63; p=0.02). Among patients with similar cumulative RAI activities, administration of multiple RAI doses was significantly and independently associated with AMH level out of range for age (HR 5.9, 1.55-52.2, p=0.014) after age adjustments.

CONCLUSION: Levels of AMH were lower after multiple RAI doses, especially after a cumulative RAI activity above 200mCi. More studies are needed to clarify the impact of RAI on fertility considering its cumulative activity and treatment strategy.