Thyroid Hemiagenesis Associated with Papillary Thyroid Carcinoma

ABSTRACT

Thyroid hemiagenesis is a rare congenital anomaly that is caused by a developmental defect of a thyroid. Previous reports indicate that thyroid cancer associated with hemiagenesis is extremely rare. A 47-year-old woman presented with single nodule in the right thyroid gland that was incidentally detected during a routine medical checkup. Ultrasonography showed a 1.5×1.2 cm sized ill-defined irregular hypoehoic nodule in the right thyroid and the isthmus was present. However, the left thyroid was not seen and thyroid was disconnected at left paraisthmic area. Fine-needle aspiration cytology confirmed that the right thyroid nodule was papillary thyroid carcinoma. Total thyroidectomy with bilateral central compartment node dissection was performed. Permanent pathologic finding was 1.3×1 cm sized classical type papillary thyroid carcinoma with nodular hyperplasia. There was extensive lymphatic invasion and 3 metastatic lymph nodes out of 4 in central compartment. In conclusion, although thyroid hemiagenesis associated with thyroid carcinoma is extremely rare, treatment strategy is not different with patients with normal anatomy. And the possibility of developing a thyroid carcinoma should be considered in patients with hemiagenesis. Furthermore, it requires awareness of anatomical difference around the thyroid gland during operation.