Thyroid nodule secondary prevention

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Mahshid Mir, M.D. [2]

Secondary prevention of thyroid nodules focuses on prevention of recurrence of nodules. Different prevention strategies may be used depending upon whether the nodule is benign or malignant. In case of a malignant nodule, the major focus is on the prevention of recurrence after removal of a primary nodule. Post-operative periodic monitoring with serum thyroglobulin levels, radioactive iodine scanning, neck ultrasound and thyroid stimulating hormone (TSH) may decrease the chances of recurrence.

Secondary prevention of thyroid nodules focuses on prevention of recurrence of nodules. Different prevention strategies may be used depending upon whether the nodule is benign or malignant:^[1][2]

• Prevention of recurrence of benign thyroid nodules may be done by performing total thyroidectomy.
• Totaly thyroidectomy is not associated with an increased risk of permanent hypoparathyroidism or recurrent laryngeal nerve damage.

Secondary prevention of a thyroid nodule is aimed at the prevention of recurrence after removal of a primary nodule (specially in case of malignant lesions). The following steps outline the secondary prevention of malignant thyroid nodules:

1. Routine screening for disease recurrence

• Measurement of serum thyroglobulin levels after total thyroidectomy.
• Post-op diagnostic radioactive iodine (RAI) scanning
• Post-op neck ultrasound

2. Serum TSH goals

• Maintain TSH levels between:
  • Non-stimulated thyroglobulin < 0.2 ng/ml : TSH should be 0.5-2.0 mU/L
  • Non-stimulated thyroglobulin greater than equal to 0.2 ng/ml: TSH should be 0.1-0.5 mU/L

3. Evaluation of response to therapy

• Serum thyroglobulin levels
• Neck ultrasound
• Whole body scanning (not routinely indicated)

4a. Excellent response to therapy

• Primary follow-up with clinical exam and non-stimulated thyroglobulin levels (TSH goal 0.5-2 mU/L)
• Non-stimulated thyroglobulin levels at 12-24 month intervals
• Periodic neck ultrasound