Soru

A $31$-year-old man comes to the physician for evaluation of a painless neck mass he noticed while shaving two weeks ago. For the past four months, he has experienced episodic, severe headaches accompanied by profound sweating and palpitations, which he attributed to work-related stress. His blood pressure is $172/98$ mm Hg, and his pulse is $108$/min. Physical examination reveals a $2.5$-cm, firm, mobile, non-tender mass in the right anterior neck. Laboratory studies show a serum thyroid-stimulating hormone (TSH) level of $6.2$ $\mu$ U/mL (normal: $0.4$–$4.0$ $\mu$ U/mL) and a free thyroxine (T4) level of $1.1$ ng/dL (normal: $0.9$–$2.4$ ng/dL). An ultrasound of the neck demonstrates a $2.3$-cm solid, hypoechoic nodule with microcalcifications in the right thyroid lobe. Fine-needle aspiration biopsy of the nodule reveals clusters of spindle-shaped cells with pleomorphic nuclei and extracellular deposits that demonstrate apple-green birefringence under polarized light after Congo red staining. Which of the following is the most appropriate next step in the management of this patient?