A dumbbell spinal mass derived from ectopic thyroid

Ectopic thyroid is a defect of embryologic development characterized by dislocation of the gland with or without an orthotopic thyroid gland, among other developmental issues. We report about an ectopic thyroid condition featured as an epidural dumbbell-shaped mass at the T6-7 level, also, with another gland located pre-tracheally. However, thyroid ectopy usually occurs along the trajectory of the embryologic migration of the thyroid, which is far from where the spine and spinal cord originate. To our knowledge, this is the first case reporting an ectopic thyroid tissue masquerading as a spinal neurogenic tumor but that the tumor was later confirmed to be an ectopic follicular variant of papillary thyroid carcinoma (FVPTC). Spinal epidural ectopy is a serious matter and we discuss some plausible explanations that may further our understanding of origination of ectopic thyroid.