1. Approach to a thyroid nodule
Andy Sher
PGY-2 Family Medicine

2. Case
44 y.o. woman, 2 cm nodule palpable in left lobe of thyroid gland at annual exam – smooth, non-tender. No lymphadenopathy
No symptoms of hyper/hypo thyroid. No compressive symptoms
Past Med Hx: HTN
Meds: HCTZ
Fam Hx: no hx of thyroid disease

3. Epidemiology Palpable thyroid nodules – 4-7% of population
Prevalence 19-67% - based on nodules found incidentally on ultrasound
4:1 women:men

4. Epidemiology Geographic areas with iodine deficiency
Thyroid carcinoma in 5-10% of palpable nodules
Following ionizing radiation, nodules develop at a rate of 2% annually

5. Presentation Majority are asymptomatic <1% cause hyperthyroidism
Neck pressure or pain if spontaneous hemorrhage

6. History Symptoms of hyper or hypothyroidism
Previous nodules, goiters, family history of autoimmune thyroid disease, thyroid carcinoma, or familial polyposis
Hashimoto’s thyroiditis – association with thyroid lymphoma

7. History – Red Flags Male < 20 years, > 65 years
Rapid growth of nodule
Symptoms of local invasion (dysphagia, neck pain, hoarseness)
Hx of radiation to head or neck
Family hx of thyroid CA or polyposis

8. Physical Exam Less than 1 cm usually not palpable
½ of all nodules detected by ultrasonography not detected by physical exam
Should also examine for lymphadenopathy

9. Physical Exam Smooth or nodular Diffuse or localized Soft or hard
Mobile or fixed
Painful or non-tender

10. Laboratory
TSH
Serum calcitonin if family hx of medullary thyroid carcinoma
Do not use thyroid function tests to differentiate benign from malignant

11. Radiology
Ultrasound
to document size, location, and character of nodule
To determine changes in size of nodules over time or to detect recurrent lesions
U/S guided biopsy decreases the incidence of indeterminate specimens

12. Radiology Thyroid scan
Can not reliably distinguish benign from malignant nodules
Cold nodules – 5-15% are malignant
Hot nodules – almost always benign

13. Fine Needle Aspiration
Should be 1st test in the euthyroid patient
Sensitivity 68-98%
Specificity %
False negative rate 1-11%
False positive rate 1-8%
Sampling errors in very large and very small nodules – minimized by u/s guided biopsy

15. Treatment Surgical treatment indications Malignancy
Indeterminate cytology and suspicious H&P
Indeterminate cytology and “cold nodule”
Toxic nodules (suppression of TSH, symptoms – a-fib) – can use radioactive iodine or surgery
Repeated recurrence of cystic lesions

16. Treatment
Benign biopsies – can be followed without surgery and monitored q 6 months by physical exam, u/s
Surveillance – change in nodule size and symptoms – repeat FNA if nodule grows.

17. Suppression treatment
Post-operative suppression treatment following resection of cancer
TSH should be maintained for target of 0.5 mU per L
Greater suppression for high risk patients, metastatic or locally invasive not completely removed

18. Suppression treatment
For benign solitary nodule controversial
Follow at 6 month intervals
Thyroxine to suppress TSH to 0.1 to 0.5 mU per L for 6-12 months
After 12 months, maintain TSH in low normal range

19. Incidental Nodule on U/S
Most are benign and can be monitored without further testing
FNA if
nodule becomes palpable
findings suggestive of malignancy on u/s
larger than 1.5 cm
Hx of head or neck irradiation
Strong family hx of thyroid cancer

20. Case
44 y.o. woman, 2 cm nodule palpable in left lobe of thyroid gland at annual exam – smooth, non-tender. No lymphadenopathy
TSH ordered – normal
Thyroid u/s – confirms 2 cm nodule, solid
FNA - benign

21. Case Repeat U/S at 1 year – nodule now 2.5 cm in size
Repeat FNA – benign
Could consider suppression therapy, or continue to follow.