J Korean Med Sci 2007; 22: 568-71 Copyright � The Korean Academy ISSN 1011-8934 of Medical Sciences Primary Malignant Teratoma with a Primitive Neuroectodermal Tumor Component in Thyroid Gland : A Case Report Teratomas comprise the most common extragonadal germ cell tumors in childhood. Eunyoung Kim, Tae Seok Bae, Most teratomas involving the thyroid are benign and occur in children. However, Youngmee Kwon, Tae Hyun Kim, the adult cases reported are mostly malignant and commonly arise in the thyroid. Ki-Wook Chung, Sun Wook Kim, We report a case of a 31-yr-old female with a huge neck mass. Pathologic examina- Jungsil Ro, Eun Sook Lee tion revealed it to be malignant teratoma composed of primitive neuroepithelial tis- Research Institute and Hospital, National Cancer sue with primitive neural tubes and loose myxoid to fibrous immature mesenchymal Center, Goyang, Korea stroma. The patient underwent extensive evaluation of the thyroid gland with com- puted tomography (CT) scan and positron emission tomography (PET) scan, which Received : 29 September 2005 revealed no evidence of metastatic disease. She underwent total thyroidectomy Accepted : 9 March 2006 with bilateral modified radical neck dissection, intensive chemotherapy and radio- therapy. At 22-months of follow-up, the patient has remained euthyroid and showed no evidence of recurrence. This is the first case, to our knowledge, of malignant Address for correspondence Eun Sook Lee, M.D. thyroid teratoma with a exuberant primitive neuroectodermal tumor component in Center for Breast Cancer, National Cancer Center, Korea. 809 Madu-1-dong, Ilsan-gu, Goyang 411-769, Korea Tel : +82.31-920-1633, Fax : +82.31-920-1759 Key Words : Malignant Teratoma; Thyroid Neoplasm; Thyroid Disease E-mail : [email protected] INTRODUCTION erogeneous enhancing mass arising in the right lobe of thy- roid gland (Fig. 1). It was invading beyond the thyroid gland Teratomas comprise the most common extragonadal germ and extended down to the anterior mediastinum. The trachea cell tumors in childhood (1). Teratomas of the neck in adults and right sternocleidomastoid muscle were deviated to the are extremely rare. The tumors of the head and neck account left. The supraclavicular, highest mediastinal, and bilateral for 5% of all benign and malignant germ cell tumors and for prevascular lymph nodes were all enlarged. The largest lymph 6% of all teratomas, where the most common sites of involve- node was over 2.5 cm at the levels II and III. ment are the soft tissue of the neck, thyroid, superficial facial The F-18-FDG positron emission tomography (PET) scan structures, oral cavity, nasopharynx, and orbit (1, 2). Most showed a huge hypermetabolic mass in the right thyroid gland teratomas involving the thyroid are benign and occur in chil- with multiple hypermetabolic lesions in the neck and in the dren. We report a case of primary malignant thyroid terato- prevascular area of mediastinum. Fine needle aspiration slides ma in a 31-yr-old female. To our knowledge, this is the first revealed diffusely scattered oval to spindle shaped atypical case of malignant teratoma with a primitive neuroectoder- cells with rare eosinophilic amorphous material suggesting mal tumor component in the thyroid in Korea. poorly differentiated carcinoma possibly consistent with me- dullary carcinoma. She underwent total thyroidectomy with bilateral modified radical neck dissection. The tumor was CASE REPORT penetrating the thyroid capsule and was invading the adja- cent tissue involving the right recurrent laryngeal nerve. The A 31-yr-old woman presented to our clinic with a two- upper portion of the sternum was cut to dissect the inferior month history of a fast growing non-tender mass in the neck. portion of right thyroid. The lymph nodes along the chain No pertinent past medical illness or family history was pre- were removed after the sheaths of the common carotid, and sent. On physical examination, a large hard and fixed mass internal jugular vein were opened. The postoperative period was palpated in the central neck, mostly occupying the thy- was uneventful except transient hypocalcemia. On the third roid gland. The laboratory findings were unremarkable, and day of operation, the total serum calcium level was 6.7 mg/ her thyroid function was normal. The computed tomogra- dL with a ionized calcium level of 0.88 mM/L. Calcium was phy scanning of the neck showed a 7.0×5.5 cm solid het- replaced by oral medication. 568 Malignant Thyroid Teratoma 569 On gross examination, the mass was occupying most of the mainly composed of primitive neuroepithelial tissue with right lobe of thyroid gland with a ill-defined border, measur- primitive neural tubes and loose myxoid to fibrous immature ing 7.5×5.0×4.7 cm. The cut surface was grayish white, mesenchymal stroma (Fig. 3). The normal thyroid follicles hemorrhagic, and necrotic with focal cystic changes. Many were intermingled or adjacent to the tumor. The tumor cells lymph nodes were grossly involved by the tumor (Fig. 2). were pleomorphic and partly necrotic with hyperchromatism The microscopic examination showed that the tumor was and frequent mitotic figures (4-6/10 high power fields). A Fig. 1. Computed tomography (CT) scan of malignant teratoma. Fig. 2. Gross finding of malignant teratoma. The mass is mainly A 7.0×5.5 cm mass is observed within the right anterior neck. located in the right lobe of thyroid with extrathyroidal extension The trachea and right sternocleidomastoid muscle are deviated and multiple lymph node involvement. to the left. Fig. 3. Microscopic findings of malignant teratoma. The tumor is Fig. 4. Microscopic findings. Mature cartilage is also noted within mainly composed of primitive neuroepithelial cells and neural tu- the primitive neuroepithelial tissue (H&E stain, ×100). bules (H&E stain, ×100). 570 E. Kim, T.S. Bae, Y. Kwon, et al. multitude of small cystic spaces was lined by mature squa- phamide and actinomycin-D (2, 6). mous or glandular epithelium. Islands of mature cartilage Chen et al. reported a 32-yr-old woman with malignant were noted within the primitive neuroepithelial tissue (Fig. thyroid teratoma who underwent a simple lobectomy of the 4). Metastases were present in 25 of total 58 lymph nodes, thyroid (8). She received chemotherapy of BEP and was still where metastatic components were only composed of a prim- alive without evidence of disease after 6.7 yr. No further local itive neuroepithelial component. The tumor cells were posi- radiotherapy or operation was arranged. tive for synaptophysin, focally positive for cytokeratin, neu- Djalilian, et al. reported a 33-yr-old woman with malignant rofilament, desmin, and CD99 on immunohistochemical thyroid teratoma who underwent 5 cycles of chemotherapy staining. The primitive neuroepithelial component comprised with vinblastin, ifosfamide, and cisplatin (1). After 3 further more than 4 in low power magnification fields (×4 objec- cycles of carboplatin and etoposide, the patient underwent tive with a ×10 ocular, using bvx.), which thus was catego- autologous bone marrow stem cell transplant. She did well rized as malignant teratoma according to the Thompson et with evidence of stable disease in the lungs at 21 months from al.’s criteria (3). the diagnosis but died of metastatic teratoma. Recently, high- After she recovered from the surgery, she was placed on dose chemotherapy in combination with autologous stem an intensive chemotherapy according to the National Can- cell transplant has been found to be effective in prolonging cer Institute protocol reported by Grier et al. (4). She received the survival in some patients with gonadal germ cell tumors 14 cycles of chemotherapy consisting of VAC (vincristine 2 (10, 11). mg, doxorubicin 75 mg/m2, cyclophosphamide 1,200 mg/ Jayaram et al. treated a malignant teratoma of the thyroid m2, every 3 weeks), alternate with IE (ifosfamide 1,800 mg/ with predominantly neuroepithelial differentiation with sur- m2 with mesna, and etoposide 100 mg/m2 for five days by gery alone (7). She died after 15 months with metastases to continuous infusion). liver, vertebra, paraaortic and paracaval lymph nodes. After the completion of the 10th cycle of chemotherapy, Craver et al. reported a 15-yr-old black girl with a malig- she received external beam radiation therapy (EBRT) with a nant thyroid teratoma with exuberant primitive neuroecto- total dose of 55.8 Gy, 5 days/week. The treated volume in- dermal tumor components. There were bilateral nodal involve- cluded the thyroid bed, cervical lymph nodes, and upper ment and mediastinal extension (6). She was treated with an mediastinum. Upon completion of radiation therapy, she aggressive combination chemotherapy of BEP and radiation. received further chemotherapy. Dactinomycin at 1.25 mg/ Further chemotherapy included vincristin, actinomycin-D, m2 replaced doxorubicin. The patient completed total 17 and cyclophosphamide alternating with ifosfamide and eto- cycles of chemotherapy. Dose reductions along with granu- poside for six cycles. These agents were included to treat the locyte colony-stimulating factor and erythropoietin supports sarcomatous component. Presently there is no residual dis- were done. ease 16 months after the diagnosis. She has been remains free of disease for 22 months after Kushner et al. treated 36 patients with poor-risk primi- the diagnosis. tive neuroectodermal tumor (12). The P6 protocol consists of high-dose cyclophosphamide, doxorubicin, and vincristine. The protocol achieved excellent pathological or clinical res- DISCUSSION ponses in 34 patients and partial responses in two patients. All six patients with metastatic disease limited to lungs Malignant teratoma of the thyroid in adult was first report- achieved a complete response and did not relapse for the fol- ed by Lurje in 1908, who described a case of a 53-yr-old wo- low-up period of 7 to 36 months. man (5). By 1999, nineteen cases of malignant teratoma of Primary thyroid malignant teratoma is rare.