Malignant Thyroid Teratoma: Report of an Aggressive Tumor in a 64-Year-Old Man

Abstract

Malignant teratoma of the thyroid is a rare and aggressive tumor, frequent in children than in adults. Histologically, thyroid teratomas usually show a predominance of a neuroectodermal component. Mature cartilage and bone may be present. We present the case of primary malignant teratoma of the thyroid in a 64-year-old man. Histologically, the tumor displayed a predominant neuroectodermal component. The diagnosis was confirmed by immunohistochemistry. The patient underwent a radical thyroidectomy with central neck dissection as primary treatment and radioiodine treatment afterwards. The patient had local and distant recurrence. A second surgery was performed with poor results and the patient died 3 months afterwards.

Malignant teratoma of the thyroid: A difficult diagnosis by fine‐needle aspiration

“…However, in most cases, the primitive nature of the malignant cells is not apparent by FNA, and the correct diagnosis has never been suggested in previous reports (Table ). On the other hand, abundant immature neuroepithelium is the defining feature of malignancy in resection specimens . As in the current case, immature neuroepithelium usually greatly predominates, sometimes to the extent that tissue from other germ cell lines may be difficult to find (Table ).…”

“…The most common sites of extragonadal disease involve midline structures such as the sacral area, retroperitoneum, and mediastinum. However, about 6% of extragonadal teratomas occur in the head and neck . Teratomas specifically involving the thyroid gland are rare, most often occur in infants and children, and are benign .…”

“…However, about 6% of extragonadal teratomas occur in the head and neck. 1 Teratomas specifically involving the thyroid gland are rare, most often occur in infants and children, and are benign. 2 Here, we report the unusual occurrence of a primary malignant teratoma of the thyroid in a young man.…”

“…2 In previous case reports of primary malignant teratoma with FNA findings, patients have ranged in age from 13 to 64 years old, and as with most other thyroid malignancies, the majority were female. 1,5,[7][8][9][10][11][12][13][14] Given the germ cell origin of thyroid teratomas, and the overall rarity of these tumors, it is interesting that four cases have been previously reported during pregnancy 15 ; all were malignant.…”

Long-Term Follow-Up of a Primary Teratoma With Somatic-Type Malignancy Within the Thyroid Gland Mimicking Thyroid Carcinoma

“…1 Whereas most teratomas involving the thyroid are benign and occur in children, the adult cases are rare and mostly malignant, 2 with one exception of recurrent benign teratoma reported by Keynes in 1959. 3 To date, 2 fatal cases of primary teratoma within the thyroid in men have been described in the literature 4,5 ; the present report is the first describing a long-term disease-free survival of 12 years after salvage chemotherapy.…”