Hürthle Cell Neoplasms

• • More aggressive variant of follicular thyroid neoplasms

  • History of radiation to the neck in some patients

  • Painless or enlarging nodule, dysphagia, or hoarseness

  • Firm or hard, fixed thyroid nodule; cervical lymphadenopathy

  • Normal thyroid function; solid nodule stippled with calcium (US), cold (radioiodine scan), positive or suspicious cytologic studies

  • Family history of thyroid cancer

Epidemiology

• • Accounts for approximately 2% of all malignant thyroid tumors

  • Appears later in life than papillary thyroid cancers, with peak incidence in fifth decade

  • More common in women

Symptoms and Signs

• • Thyroid nodule: Hard, rubbery, or soft

  • Enlarged or hard cervical lymph nodes

  • Pain in the thyroid or paralaryngeal neck

  • Hoarseness

  • Dyspnea

  • Stridor

  • Dysphagia

Laboratory Findings

• • Normal thyroid-stimulating hormone (TSH)

Imaging Findings

• • Solid or cystic nodule on US

  • Nonfunctioning (cold) on radioiodine scan

• • Fine-needle aspiration (FNA) is unable to reliably differentiate the atypical cells of invasive Hürthle adenocarcinoma from its counterpart benign adenoma

  • Sometimes bilateral and multicentric

  • Commonly metastasize to cervical lymph nodes

  • 95% resistant to radioiodine

Rule Out

• • Concurrent hyperparathyroidism (so that it can be treated during the same operation if necessary)

• • Complete history and physical exam

  • -With attention to risk factors, family history, palpable characteristics of the nodule, or lymphadenopathy

  • Measurement of serum TSH and calcium

  • FNA biopsy

• • Treatment starts with operative removal

  • External beam radiation may palliate nonresectable metastases that are resistant to radioiodine

Surgery

Indications

• • All Hürthle cell neoplasms should be excised unless the Hürthle cell adenoma can be diagnosed with certainty on FNA

  • Bulky or palpable nodal recurrences

Medications

• • Suppressive doses of thyroid hormone after thyroid ablation or thyroidectomy

Treatment Monitoring

• • Semiannual or yearly neck exams, serum thyroglobulin, thyroglobulin antibodies, and whole body radioiodine scan

Complications

• • Neck hematoma

  • Superior laryngeal nerve injury

  • Recurrent laryngeal nerve injury

  • Transient of permanent hypoparathyroidism

  • Wound infection

Prognosis

• • Worse prognosis predicted by extensive angioinvasion, older age, and presence of distant metastases

  • 10-year survival rate, approximately 70%

References

Practice Guidelines

• • NCCN web site

  • http://www.nccn.org/