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Approach to the Patient With a Thyroid Nodule


Glenn D. Braunstein

, MD, Cedars-Sinai Medical Center

Reviewed/Revised Aug 2022 | Modified Sep 2022

Thyroid nodules are benign or malignant growths within the thyroid gland. They are common, increasingly so with increasing age.

The reported incidence of thyroid nodules varies with the method of assessment. In middle-aged and older patients, palpation reveals nodules in about 5%. Results of ultrasonography and autopsy studies suggest that nodules are present in about 50% of older adults. Many nodules are found incidentally on head and neck imaging studies done for other disorders.


Evaluation of a Thyroid Nodule


Thyroid nodules may be painful or asymptomatic. Pain suggests thyroiditis or hemorrhage into a cyst. An asymptomatic nodule may be malignant but is usually benign.

Risk factors for thyroid cancer include

Physical examination

Signs that suggest thyroid cancer include stony, hard consistency or fixation to surrounding structures, cervical lymphadenopathy, and hoarseness (due to recurrent laryngeal nerve paralysis).


  • Thyroid-stimulating hormone (TSH)

  • Antithyroid peroxidase antibodies

If thyroid-stimulating hormone (TSH) is low (consistent with hyperthyroidism), radioiodine scanning is done. Nodules with increased radionuclide uptake (hot) are seldom malignant.

Ultrasonography is useful in determining the size of the nodule, but may not allow a distinction between a benign or malignant lesion. Thyroid cancer is suggested by nodule hypoechogenicity; marked internal vascularity; irregular borders; height of the nodule being greater than the width; irregular macrocalcifications; fine, stippled psammomatous microcalcifications (papillary thyroid carcinoma); or dense, homogenous irregular calcification (medullary thyroid carcinoma).

For nodules with suspicious features, fine-needle aspiration biopsy (FNAB) done under ultrasound guidance is the procedure of choice and the most economical means to distinguish benign from malignant nodules. FNAB is generally not recommended for nodules <1 cm or for nodules that are entirely cystic.

Cytologic examination of the cells obtained from FNAB may distinguish benign from malignant lesions. For lesions that are cytologically indeterminate, molecular analysis of the FNAB aspirate for mutations and rearrangements, or measurement of calcitonin for possible medullary carcinoma may add sufficient diagnostic clarity to allow an optimally informed treatment recommendation.

Treatment of a Thyroid Nodule

  • Treatment of underlying disorder

Treatment is directed at the underlying disorder (1 Treatment reference Thyroid nodules are benign or malignant growths within the thyroid gland. They are common, increasingly so with increasing age. (See also Overview of Thyroid Function.) The reported incidence... read more ). Nodules in patients with Hashimoto thyroiditis or other causes of goiter associated with hypothyroidism may stabilize or shrink with thyroxine replacement in doses that render the patient euthyroid. For small benign nodules not associated with hypothyroidism, thyroxine suppression of TSH effectively shrinks the nodule in no more than half the cases, and is seldom done. Thyroxine is not used to treat cancerous nodules Thyroid Cancers There are 4 general types of thyroid cancer. Most thyroid cancers manifest as asymptomatic nodules. Rarely, lymph node, lung, or bone metastases cause the presenting symptoms of small thyroid... read more .

Large benign nodules that compress the surrounding neck structures may become smaller following radiofrequency ablation. Partial or complete thyroidectomy are effective for treating nodules that continue to grow or cause compressive symptoms.

Toxic nodules may be treated with radioactive iodine to control hyperthyroidism and reduce nodule size.

Nodules that are not due to thyroid cancer, are not causing compressive symptoms and are not associated with either hypothyroidism or hyperthyroidism may be safely followed by periodic neck examination and, if there is suspicion of nodule growth, by repeat ultrasound evaluation.

Treatment reference

  • 1. Haugen BR, Alexander EK, Bible KC, et al: 2015 American Thyroid Association Management Guidelines for Adult Patients with Thyroid Nodules and Differentiated Thyroid Cancer: The American Thyroid Association Guidelines Task Force on Thyroid Nodules and Differentiated Thyroid Cancer. Thyroid 26(1): 1–133, 2016. doi: 10.1089/thy.2015.0020

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