Low expression of sodium iodide symporter expression in aggressive variants of papillary thyroid carcinoma

摘要

Background A decreased radioiodine uptake is associated with high recurrence rate and reduced survival in papillary thyroid carcinoma (PTC). Sodium iodide symporter (NIS) expression status in aggressive PTC variants is unknown. Methods NIS expression in conventional PTC and aggressive PTC variants such as tall cell variant (TCV) and diffuse sclerosing variant (DSPTC) was investigated using immunohistochemical detection. Results Patients having TCV and DSPTC were significantly more likely to have extrathyroidal extension and lymph nodes metastases (P < 0.05). Positive NIS staining was identified in 228 of 312 (73.1 %) patients with conventional PTC, 9 of 28 (32.1 %) patients with TCV and 12 of 30 (40.0 %) patients with DSPTC. NIS expression distinguished conventional PTC from TCV and DSPTC significantly (P < 0.01). Conclusion Due to their low NIS expression, TCV and DSPTC need higher cumulative doses of radioactive iodine therapy to improve their prognosis.