A High Prevalence of Dual Thyroid Ectopy in Congenital Hypothyroidism: Evidence for Insufficient Signaling Gradients during Embryonic Thyroid Migration or for the Polyclonal Nature of the Thyroid Gland?

Abstract

Almost one in 10 cases with congenital hypothyroidism due to thyroid ectopy has dual ectopy. This suggests that two populations of cells diverged at an early stage of development, which may arise from insufficient signaling gradients in surrounding tissues during early organogenesis or may indirectly support the polyclonal nature of the thyroid.