What is the optimal initial treatment of low-risk papillary thyroid cancer (and why is it controversial)?

Abstract

The incidence of papillary thyroid cancer has been rising steadily over the past 3 decades. Most tumors in this setting are regarded as low risk, but recurrence rates are high, producing controversy about initial therapy. Microcarcinomas smaller than 1 cm are generally best treated with lobectomy alone. Total thyroidectomy should be performed for tumors 1 cm or larger or for tumors that have metastasized. Prophylactic central and lateral neck lymph node compartment dissection uncovers unsuspected metastases in about half the patients, which may alleviate the need for postsurgical radioiodine therapy but can be associated with surgical complications. Radioiodine may diminish tumor recurrence but is complicated by injury to nonthyroidal tissues and by dose-related nonthyroidal cancers that occur in a small number of patients. Tumors that are metastatic, invasive, or multifocal or have aggressive histologic features should be treated with radioiodine. Total-body irradiation can be significantly reduced by preparing the patient with recombinant human thyrotropin and by using smaller amounts of radioiodine (approximately 30 mCi). The natural history of papillary cancer is such that patients who achieve disease-free status after total thyroidectomy and radioiodine therapy usually achieve normal life expectancy.