Ectopic thyroid gland located on the L4 vertebral body: A case report

RATIONALE: The prevalence of ectopic thyroid is extremely low, with the condition observed in approximately 1 in 100,000 to 300,000 people. Thyroid gland ectopia develops as a result of the presence of developmental abnormalities during the migration of the thyroid anlage from the floor of the primitive foregut to its final position in the neck. Ectopic thyroid tissue is commonly observed in the lingual region, but can also present in other head and neck regions, as well as regions located at a large distance from the neck. PATIENT CONCERNS: A 67-year-old woman who had experienced left lumbago and leg pain was transferred to our hospital following the worsening of her lumbago-related symptoms in the 2 months preceding her presentation. Seven years ago, the patient had recurrent lumbago and leg pain without obvious inducement, and visited a local clinic for treatment. The severity of her symptoms fluctuated; their intensity increased after participation in activities and decreased after rest. DIAGNOSES: The patient was diagnosed as having an ectopic thyroid gland that was located on the L4 vertebral body. INTERVENTIONS: The patient chose to undergo surgery, with supportive care, following tumor discovery. OUTCOMES: After surgical treatment, the degree of lumbar spinal stenosis improved, and the patient's clinical symptoms were alleviated. LESSONS: Clinically, ectopic goiter is diagnosed through radionuclide thyroid imaging, ultrasound examination, computed tomography, magnetic resonance imaging, and biopsy pathology. However, the imaging manifestations in this case were atypical, leading to greater diagnostic difficulties. A conclusion was finally reached based on pathology.