Surgical approach and radioactive iodine therapy for small well-differentiated thyroid cancer

Abstract

Management of small well-differentiated thyroid cancer (DTC) has generated much debate regarding the surgical approach and radioactive iodine treatment (RAI). The aim of the study was to evaluate the impact of surgical extension and RAI on the outcome of DTC ≤2cm. A retrospective analysis of 176 cases of DTC ≤2cm was performed. At diagnosis, tumor size was 1.38±0.55cm, age 40.2±13.6years. After a mean follow-up period of 14.1±4.5years, 15.9% patients had recurrent/persistent structural disease, with cervical neck disease (thyroid gland area and/or cervical lymph nodes) in 11.9% cases and distant metastasis in 5.1%. Disease specific mortality was of 1.1%. No difference in outcome was observed between patients submitted to total or subtotal thyroidectomy. After total and subtotal thyroidectomy, the rate of recurrent/persistent structural disease was 19.1 and 10.6% (p=1.00), respectively. Using the multivariate cox proportion hazards analysis, no difference in the clinical outcome was observed after total or subtotal thyroidectomy (p=0.703) neither after RAI (p=0.807). Similar results were observed after stratification by tumor size. Multifocal disease (p=0.007), extra-thyroid extension (p=0.007) and presence of lymph node metastasis (p=0.000) were associated with unfavorable outcome. Total thyroidectomy and RAI did not improve clinical outcomes of DTC ≤2.0cm when compared with less extensive surgery and no RAI in selected patients. Therefore, in carefully selected patients with DTC ≤2.0cm and no unfavorable risk factors (multifocal disease, extra-thyroid extension, lymph node and/or distant metastasis), less extensive surgery and no RAI may be acceptable treatment options.