II. Epidemiology
-
Incidence of Thyroid Carcinoma: 44,000/year (as of 2024, U.S.)
- Three fold increased Incidence in 40 years is a result of greater detection
- Gender: 70% of cases are in women
- Age: Mean onset at 51 years old
- Less common in black patients
-
Incidence by Nodule type
- Single Nodules: 5-10% are carcinoma
- Multinodular Goiter: <5% are carcinoma
III. Types: Thyroid Carcinoma
- Papillary carcinoma (80 to 84%)
- Insidious growth
- May go undiagnosed until metastases
- Follicular Carcinoma (4 to 25%)
- Female > Male
- Peaks at age 50-60 years
-
Medullary Carcinoma (5-10%)
- Secretes multiple substances including Calcitonin
- Associated with Multiple Endocrine Neoplasia
- MEN 2a (Sipple's Syndrome)
- Pheochromocytoma and Parathyroid hyperplasia
- MEN 2b
- Pheochromocytoma and mucosal neuroma
- MEN 2a (Sipple's Syndrome)
- Undifferentiated Carcinoma (5-10%)
- Thyroid Lymphoma (5%)
IV. Risk Factors (and Red Flags)
- Male gender (especially under age 40 years)
- Age extremes (under age 20 and over age 65)
- Rapid painless growth of Thyroid Nodule
- Local symptoms consistent with invasion
- Dysphagia
- Neck Pain
- Hoarseness or raspy voice
- Head and neck radiation history
-
Family History of Thyroid malignancy
- Thyroid Cancer
- Thyroid polyposis (Gardner's Syndrome)
- Thyroid fixation to skin or trachea
- Hard Nodule on palpation
V. Evaluation
- See Thyroid Nodule
- Most Thyroid Cancers are asymptomatic (found incidentally on imaging, or palpated on exam)
VI. Management: Thyroid Cancer
- Unilateral microcarcinomas (=1 cm or up to 1.5 cm)
- Consider observation without surgical resection
- Tumors >1 cm with or without Lymph Node metastases
- Surgery with or without Radioactive Iodine
- Treatment is curative in most cases of well-differentiated Thyroid Cancer
- Recurrent local or regional disease
- Surgical resection
- Metastatic Thyroid Cancer
- Surgical resection or stereotactic body irradiation
- Advanced Thyroid Cancer AND genetic mutations (BRAF, RET, NTRK, MEK)
- Dabrafenib
- Selpercatinib
- Thyroid Cancer not responding to Radioactive Iodine
- Antiangiogenic multikinase inhibitors (eg, Sorafenib, Lenvatinib, Cabozantinib)
- Radioactive Iodine response varies by genetic mutation
- RAS Mutations respond to Radioactive Iodine
- BRAF V600E mutations tend not to respond to Radioactive Iodine
VII. Management: Cancer Survivor Care
- See Cancer Survivor
- Follicular, Hurtle Cell or Papillary Cancer
- Visits (history, exam, labs) at 6 and 12 months, then yearly
- Labs at 6 and 12 months, then yearly
- Thyroid Stimulating Hormone (TSH)
- Thyroglobulin Antibody
- Thyroglobulin
- Ultrasensiitive Thyroglobulin if treated with Radioactive Iodine
- Imaging
- Neck Ultrasound every 6 months for 1 to 2 years, then yearly
- TSH stimulated whole body Radioiodine imaging if high risk for metastatic disease
-
Medullary Cancer
- Serum Calcitonin every 6 to 12 months
- Carcinoembryonic Antigen (CEA Antigen) every 6 to 12 months
- Additional testing for Multiple Endocrine Neoplasia 2A or 2B
- Urine or plasma metanephrine yearly
- Plasma Parathyroid Hormone test yearly
- References
VIII. Prognosis
- Overall 5 year survival: 98%
- Papillary carcinoma has the best prognosis of Thyroid Cancer
- Medullary Carcinoma and Follicular Carcinoma have a more variable prognosis
- Undifferentiated Thyroid Cancer and anaplastic Thyroid Cancer have a worse prognosis