Multifocal papillary thyroid cancer in children and adolescents: 12-year experience in a single center

Background: Thyroid cancer is the most common endocrine malignant disease in children and adolescents. There is a trend of more conservative strategies including lobectomy and less radioactive iodine therapy (RAI) in multifocal papillary thyroid cancer (PTC) for its good survival outcome. The aim of our study was to define long-time outcome of a large cohort of multifocal PTC patients less than 20 years old treated at our institution. Methods: Data were collected from 276 cases who were initially diagnosis of PTC under the age of 20 from January 2006 to December 2015 at Fudan University Shanghai Cancer Center. All patients received total/near total thyroidectomy or lobectomy. Therapeutic central-compartment (level VI) and lateral neck lymph node dissection performed for patients with clinically involved neck nodes. RAI therapy used in selected patients. No patients received chemotherapy or kinase inhibitor therapy. Thyroid-stimulating hormone (TSH) suppression therapy was performed in all patients for at least 5 years. Results: Ninety among 276 were multifocal PTC patients and included in this study. The median followup time was 54.28 months, ranging from 6.10 to 141.27 months. Fifteen patients had tumor recurrence during the follow-up. On Kaplan-Meier survival curves, lymphovascular invasion and extrathyroidal extension was associated with a decline in recurrence-free survival. However, there was no difference in recurrence-free survival curves in patients no matter which treatment they had received, either lobectomy or total thyroidectomy, RAI or not. Conclusions: More conservative strategies including lobectomy and less RAI in multifocal PTC among children and adolescents are safe and effective.