A 60-year-old gentleman with past medical history of cervical disk herniation presented with a 3-year history of progressive fatigue and bilateral upper extremity weakness. MRI was performed to evaluate the spine and was consistent with cervical spinal stenosis. T2 non-contrast images incidentally revealed an infiltrating mass in the left thyroid that was incompletely visualized. Ultrasound-guided fine needle aspiration showed atypia of undetermined significance. The patient was referred to surgery and was noted to have dysphonia but no stridor or dysphagia. The differential diagnosis was felt to include papillary thyroid carcinoma, follicular thyroid carcinoma, rare thyroid neoplasms including Hurthle cell carcinoma or anaplastic carcinoma, abscess, or autoimmune thyroid disease. He underwent total thyroidectomy with central neck dissection. On exploration, the thyroid mass was seen encasing the left recurrent laryngeal nerve and was shaved off the nerve and the trachea. The nerve was not stimulatable after resection and the patient developed left vocal cord paralysis. The tumor grossly measured 7 cm with extrathyroidal extension. There was lymphvascular space invasion and perineural invasion. Three lymph nodes were identified, and all were negative. Surgical margins had extensive involvement of tumor. Histopathologic analysis of the specimen showed high-grade carcinoma with thymus-like differentiation. Immunohistochemical staining was positive for pan-CK, p63 (cyokeratin and epithelial markers) and negative for chromogranin, thyroglobulin, and calcitonin (neuroendocrine, papillary and follicular thyroid, and medullary makers, respectively).\nThe tumor was arranged in broad, pushing, smooth-bordered islands abutted against a lymphocyte rich stroma. The lobules of tumor were surrounded by lymphocytes and plasma cells (Figures and ). The tumor cells were squamoid and syncytial to spindled, with eosinophilic cytoplasm, and the nuclei show mild pleomorphism with pale vesicular chromatin. The neoplastic cells were strongly immunoreactive for pancytokeratin and p63, as shown in Figures and . These cells were also strongly positive for CD5, which marks background T lymphocytes (Figure ). The neoplastic cells were non-reactive with TTF1 and thyroglobulin.\nPostoperative staging surveillance with PET scan was performed for systemic staging and due to positive margins. It showed no abnormal FDG uptake at distant sites and increased uptake at the operative bed, indeterminate between residual disease and postoperative changes. The patient underwent adjuvant treatment with radiation therapy to 64 Gy in 32 fractions with intensity modulated radiotherapy. Concurrent chemotherapy was given based on his extensive positive margins for radiosensitization. A dose of 60 Gy was delivered to the bilateral neck including paratracheal nodes into the upper mediastinum, with a 4 Gy sequential boost to the operative site. A coronal section of the radiotherapy plan is shown in Figure . Six cycles of intravenous concurrent cisplatin 35 mg/m2 were infused. During therapy, he developed grade 2 skin reaction characterized by dry desquamation and moderate erythema of the neck and upper chest. Skin moisturizer was used for therapy. He experienced grade 2 esophagitis and mucositis of the oropharynx and grade 2 nausea requiring topical analgesics, oral narcotics, antiemetics, and intravenous fluid administration. Weight decreased from 108 to 95.5 kg by the end of therapy. Nutritional counseling by dietician and oral nutritional supplementation were provided. With chemotherapy, the patient developed a tinnitus grade 1. Toxicities are reported per the Common Terminology Criteria for Adverse Events ().\nAfter treatment, the patient initially experienced continued weight loss, and as a result underwent percutaneous endoscopic gastrostomy tube placement. Five months after end of treatment, the tube was removed after the patient was able to gain significant weight and completely obtain nutrition per oral route for 6 weeks. Dysphagia to solid foods is improving. He experienced persistent dysphonia secondary to left vocal cord paralysis since surgery and underwent left medialization thyroplasty 1 year later. He displayed improvement in voice quality. At 3-years follow-up after completion of radiotherapy, our patient is without evidence of locally recurrent or distant disease.
Patient 1 was a 61-year-old female who presented with a 5-cm anterior neck mass with retrosternal extension. She was surgically treated with a right thyroid lobectomy at another institution. The lesion was interpreted to be a poorly differentiated papillary thyroid cancer. Postoperative treatment consisted of sequential and combined chemoradiotherapy. Local recurrence in the region of the right thyroid occurred 20 months later, and radiotherapy was performed to relieve symptoms. Six years later, the patient had local recurrence again and was referred to our institution for further treatment. After curative wide local excision and central neck dissection, postoperative radiotherapy was given to the thyroid bed and bilateral cervical lymph node areas (55 Gy/16 fractions). Histological re-evaluation of the recurrent tumor specimens revealed CASTLE (pT4bN1M0). A third local recurrence was diagnosed 1 year later, and concurrent chemotherapy (paclitaxel 210 mg/m2 and cisplatin 40 mg/m2) and radiotherapy (50.4 Gy /28 fractions) were applied. The patient died from acute respiratory distress 1 month after the initiation of treatment.