A 42-year-old woman undergoes total thyroidectomy for papillary thyroid carcinoma. During dissection of the right lobe near the inferior thyroid artery, the surgeon notices the recurrent laryngeal nerve (RLN) is adherent to a large lymph node. Careful dissection is attempted, but the nerve appears to be invaded by tumor. The nerve cannot be separated cleanly. What is the most appropriate next step?