Patient 2 was a 48-year-old male pathologically diagnosed with stage pT4aN0M0 CASTLE postsurgery. He presented with rapidly growing thyroid nodules with fixation to underlying structures. He underwent total thyroidectomy with central neck dissection. On exploration, the thyroid mass was seen extended to the left laryngeal nerve, strap muscle, trachea, and esophagus. Curative wide local excision was attempted on patients with gross residual local disease. Postoperative external beam radiation therapy (50.4 Gy/28 fractions) was given to the thyroid bed and bilateral cervical lymph node area. He remained well 2 years post therapy with no palpable neck 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.