Differential Diagnosis for a 19-year-old Female with a 1.6 cm Thyroid Nodule (TRADS 4)
- Single Most Likely Diagnosis
- Benign thyroid adenoma: This is the most common cause of a solitary thyroid nodule in young adults, and the majority of these nodules are benign.
- Other Likely Diagnoses
- Colloid cyst or nodule: These are common benign thyroid lesions that can present as a solitary nodule.
- Thyroid cyst: Simple thyroid cysts can occur and may be detected incidentally.
- Hashimoto thyroiditis: Although more commonly associated with diffuse thyroid enlargement, Hashimoto thyroiditis can sometimes present with a solitary nodule.
- Follicular thyroid neoplasm (including follicular adenoma and carcinoma): While less common than benign adenomas, follicular neoplasms are a consideration, especially given the size of the nodule.
- Do Not Miss Diagnoses
- Papillary thyroid carcinoma: Although less likely, thyroid cancer, particularly papillary carcinoma, is a critical diagnosis not to miss due to its potential impact on prognosis and treatment.
- Medullary thyroid carcinoma: This rare type of thyroid cancer can present with a solitary nodule and has significant implications for treatment and genetic screening.
- Anaplastic thyroid carcinoma: Although very rare and more common in older adults, anaplastic thyroid carcinoma is aggressive and deadly, making it crucial not to miss.
- Rare Diagnoses
- Thyroid metastasis: Metastasis to the thyroid from other cancers (e.g., breast, lung, kidney) is rare but can occur.
- Thyroid lymphoma: Primary thyroid lymphoma is rare and usually occurs in the setting of chronic lymphocytic thyroiditis.
- Teratoma or other germ cell tumors: These are extremely rare in the thyroid gland.
- Parathyroid adenoma: Although not a thyroid nodule per se, a parathyroid adenoma can sometimes be mistaken for a thyroid nodule due to its location.