Distinguishing Molecular Markers in Thyroid Tumors: A Tribute to Dr. Orlo Clark

Excerpt

Because the surgical management of benign and malignant thyroid neoplasms differ, and because the distinction between benign and malignant thyroid lesions that are indeterminate or inadequate on fine needle aspiration biopsy (FNA) cannot be made preoperatively or intraoperatively, surgeons typically decide upon the surgical management based on clinical presentation, rapidity of tumor growth, gross intraoperative findings of invasion, and/or frozen section results, all of which are notoriously inaccurate [1‐7]. Near-total or total thyroidectomy for every patient with an indeterminate FNA at the first operation is unacceptable, because at least 50% of the lesions suspicious for papillary thyroid cancer or the follicular variant of papillary thyroid cancer and 80% of all FNAs suspicious for follicular or Hürthle cell neoplasms are ultimately determined to be benign on final histopathology [8‐10]. Furthermore, patients with benign lesions would unnecessarily be subjected to the increased surgical risks of hypoparathyroidism and recurrent laryngeal nerve injury on the contralateral side, as well as a lifelong requirement for thyroid hormone replacement. A second option, and one that is frequently practiced, includes performing unilateral lobectomy alone for all indeterminate lesions. However, in this scenario, surgeons then encounter the situation in which they need to perform a completion thyroidectomy days after an initial operation, and once a diagnosis of carcinoma has been rendered on permanent histological section, a practice that can be riskier than a single operation. Because of this clinical dilemma, additional diagnostic markers for thyroid malignancy are greatly needed. …