Biochemical follow-up of nonfunctioning benign thyroid nodules

Area of Science:

• Endocrinology
• Thyroidology
• Biochemistry

Background:

• Lifelong thyroid-stimulating hormone (TSH) monitoring is recommended for benign thyroid nodules to detect toxic nodules.
• The clinical utility of frequent TSH monitoring requires re-evaluation.

Purpose of the Study:

• To assess the incidence of thyroid dysfunction in patients with benign thyroid nodules and normal initial TSH.
• To identify predictors of biochemical dysfunction over time.

Main Methods:

• Retrospective review of 157 patients with thyroid nodules diagnosed between January 2011 and August 2014.
• Inclusion criteria: TSH measurement within 1 year of initial diagnostic ultrasound.
• Analysis of factors predicting thyroid dysfunction over a median follow-up of 45 months.

Main Results:

• 13 (8.3%) patients developed thyroid dysfunction.
• Initial TSH <1 mIU/L was associated with a higher incidence of dysfunction (P=.022).
• Mean initial TSH differed significantly between patients who developed dysfunction and those who did not (0.65 vs 1.37 mIU/mL, P=0.007).

Conclusions:

• Re-examine the practice of frequent TSH monitoring for all patients with thyroid nodules.
• Consider less frequent monitoring for patients with an initial TSH level ≥1 mIU/L.