Simultaneous Occurrence of Thyroiditis in Ectopic and Eutopic Thyroid Masquerading as Thyroglossal Cyst

Chronic thyroiditis in lateral ectopic thyroid mimicking cervical metastasis of thyroid cancer

SUMMARY

We present the case of a 45-year-old Caucasian woman who attended the Endocrinology Unit for a left cervical mass discovered during follow-up for autoimmune chronic thyroiditis. The ultrasound-guided fine-needle aspiration biopsy of the lesion was consistent with a metastasis of follicular thyroid carcinoma. The sonographic neck evaluation revealed no thyroid nodules but three markedly hypoechoic and highly vascularized areas, with irregular margins and hyperechoic spots. In the clinical suspicion of primary thyroid neoplasm, ultrasound-guided fine-needle aspiration biopsy of two of the three areas was performed, but both cytological reports were non-diagnostic, revealing only colloid and blood. Subsequently, the patient underwent surgical removal of the cervical mass, with the intra-operatory consultation with frozen section examination suggesting follicular-like neoplasia. For this reason, thyroidectomy with both central and lateral neck dissection was performed. Surprisingly, the final histologic examination revealed chronic thyroiditis in the thyroid specimen and no evidence of metastasis in the left neck mass. Consequently, the pathological revision of the frozen section assessment led to the final diagnosis of chronic thyroiditis on the lateral ectopic thyroid. This case represents an uncommon example of lateral ectopic thyroid tissue with coexisting normally located thyroid tissue both affected by chronic thyroiditis.

LEARNING POINTS

Ectopic thyroid must be considered in the diagnostic work-up of lateral neck mass. Even if rare, ectopic thyroid tissue can be found lateral to the carotid sheath and with coexisting normally located thyroid tissue. As the orthotopic tissue, lateral ectopic thyroid tissue can be affected by chronic thyroiditis, which may complicate the diagnosis both on ultrasound and cytology.

A Uniquely Challenging Case of Poorly Controlled Hyperthyroidism With a Coexisting Thyroglossal Cyst

Hyperthyroidism is a common disease. Thyroglossal duct cysts are also a very common type of congenital anomalies. Their co-existence is, however, rare with only a few cases described in the literature of the same. We describe the case of a 44-year-old female who presented initially 16 years ago with hyperthyroid symptoms related to Graves’ disease diagnosed serologically and by thyroid scan and ultrasound. Incidentally, she was also noted to have a non-complicated thyroglossal duct cyst. She was initially started on anti-thyroid medications but remained in a hyperthyroid state throughout most of her illness. Radioiodine ablative therapy and surgical resection were delayed due to the patient’s dispreference. After a long period of missed follow up, she presented with a thyroid storm and underwent a total thyroidectomy and cyst resection. The key endocrine issues learned from this case include: 1) dealing with non-compliant patients in terms of poorly controlled hyperthyroidism and refusal to follow the recommended treatment, 2) observing the natural disease progression of untreated Graves’ disease coexisting with a thyroglossal duct cyst, and 3) describing a rare incidental finding of a thyroglossal duct cyst coexisting with Graves' disease in the absence of ectopic hormone production. A few cases have described hyperthyroidism related to remnants of thyroid tissue in the thyroglossal duct or related to the thyroid gland. To the best of our knowledge, there are no cases reported of Graves’ disease coexisting with a non-complicated thyroglossal duct cyst making our case unique and first of its kind.