A 60-year-old female presented with a neck mass that had been present for some time, associated with discomfort. Her past medical and surgical histories were unremarkable, with no significant family history. She was not taking any regular medications.

Thyroid function tests were within normal limits, with TSH 1.72 µIU/mL, free T4 15.61 pmol/L, and total T3 1.21 ng/mL, consistent with a euthyroid state. Serum calcitonin was <0.500 pg/mL, which is within the normal range for females and showed no biochemical evidence of elevated calcitonin. Overall, the laboratory findings demonstrated normal thyroid function with a normal serum calcitonin level.

Ultrasound of the thyroid demonstrated a mildly enlarged right thyroid lobe, measuring 74 × 38 × 30 mm, while the left lobe was normal in size, measuring 50 × 16 × 15 mm. The isthmus measured 4 mm. Both lobes showed homogeneous echotexture. A large solid hypoechoic nodule measuring 49 × 35 × 28 mm was identified, occupying most of the right thyroid lobe. The nodule had a focally irregular surface along the posteromedial aspect, with microcalcifications and macrocalcifications, as well as increased perinodular and intranodular vascularity. The lesion was classified as TI-RADS 5 (TR5), highly suspicious. Several smaller nodules measuring less than 6 mm and classified as TR3 were also seen in both thyroid lobes, consistent with multinodular goiter (MNG). Multiple highly suspicious central cervical lymph nodes were identified, with the largest measuring 21 × 14 mm and located below the right lower thyroid pole, with partial retrosternal extension. Multiple enlarged and highly suspicious lateral cervical lymph nodes were also noted, the largest measuring 40 × 27 mm in right level II. No significant left lateral cervical lymphadenopathy was identified. The bilateral parotid and submandibular glands appeared normal, with no focal lesions.

Contrast-enhanced CT demonstrated a large, well-defined but irregular-surfaced solid enhancing nodule involving the right thyroid lobe, measuring approximately 38 × 31 × 30 mm. The lesion was heterogeneous with areas of cystic necrosis and macrocalcification, corresponding to the previously identified TR5 nodule on ultrasound. There was posterior and medial extension, with no definite preserved cleavage plane between the lesion and the right lateral wall of the esophagus, raising suspicion for possible esophageal involvement. Multiple pathological right cervical lymph nodes were identified, including enlarged nodes at right level II, the largest measuring approximately 28 × 25 mm, as well as abnormal central compartment lymph nodes measuring up to 22 × 15 mm, consistent with metastatic nodal disease. No significant left cervical lymphadenopathy was identified. Multiple small bilateral pulmonary nodules measuring 4 mm or less were noted, in keeping with pulmonary metastatic deposits in the clinical context. No dominant lung mass, consolidation, pleural or pericardial effusion, or mediastinal/hilar/axillary lymphadenopathy was identified. The remaining abdominal and pelvic viscera showed no definite focal metastatic lesions.

Fine-needle aspiration cytology of the right thyroid lobe nodule was positive for malignancy, confirming papillary thyroid carcinoma (Bethesda VI). The thyroid aspirate demonstrated characteristic nuclear features, including irregular nuclear membranes, nuclear grooves, and intranuclear pseudoinclusions. Fine-needle aspiration of the right group II cervical lymph node was also positive for malignancy and consistent with metastatic papillary thyroid carcinoma. Overall, the cytological findings confirmed papillary thyroid carcinoma of the right thyroid lobe with metastatic involvement of the right cervical lymph node.

Under general anesthesia, the patient was placed in the supine position with the neck extended. Through an extended collar incision, total thyroidectomy with bilateral central lymph node dissection and right lateral lymph node dissection was performed. The bilateral recurrent laryngeal nerves and parathyroid glands were identified and preserved. The right recurrent laryngeal nerve was found to be invaded by the tumor, and the right internal jugular vein was ligated. Hemostasis was secured, and a Redivac drain was placed. The wound was subsequently closed in layers.

Histopathology of the total thyroidectomy with bilateral central and right lateral cervical lymph node dissection revealed a 3.6 cm unifocal, well-differentiated papillary thyroid carcinoma, conventional subtype, arising in the right thyroid lobe. The tumor demonstrated lymphovascular and perineural invasion, with minimal extrathyroidal extension and no tumor necrosis. The mitotic activity was low at 1–2 mitoses per 2 mm², and no tumor capsule was identified.

A total of 55 lymph nodes were examined, of which 6 were positive for metastatic carcinoma with extranodal extension. Metastatic disease was identified in 3 of 7 right central lymph nodes and 3 of 40 right lateral lymph nodes, while all 8 left central lymph nodes were negative for tumor. Other findings included thyroid follicular nodular disease with focal lymphocytic thyroiditis and an ultimobranchial remnant in the isthmus. No parathyroid tissue was identified.

The patient had an uncomplicated postoperative course following surgery. The patient was followed postoperatively for wound healing and recovery, with referral for appropriate oncology follow-up and consideration of adjuvant radioactive iodine therapy.