Ectopic intrapulmonary thyroid: a case report

Abstract

An ectopic thyroid is caused by abnormalities in migration of the thyroid during development and rarely occurs in the thoracic cavity or the abdominal cavity. We report the case of a 64-year-old female who had abnormal findings from a thyroid hormone test during follow-up after thyroid cancer surgery. Based on the radioisotope diagnostic test, an ectopic thyroid inside the thoracic cavity was suspected. Through surgical treatment, the patient was diagnosed with ectopic intrapulmonary thyroid. Ectopic intrapulmonary thyroid is reported to be very rare and the case is described along with a literature review.

Keywords: Lung neoplasm; Thyroid dysgenesis; Thyroid neoplasms.

Fig. 1

I-131 scan: extrathyroidal distant functioning metastasis. RT, right; LT, left; ANT, anterior; POST, posterior.

Fig. 2

Chest computed tomography: a 1.2 cm ovoid lesion with homogeneous enhancement in the left lower lobe (se2/31).

Fig. 3

Intraoperative findings.

Fig. 4

Microscopically, there is shallow demarcation of the fibrous capsule between the solid mass and lung parenchyme (H&E, ×100).

Fig. 5

On low magnitude power, the solid mass is composed of thyroid tissue. Variably sized follicle structures and benign follicular cells were found (H&E, ×100).