• Benign thyroid nodule, eg, adenoma, cyst
• Subacute thyroiditis
• Benign multinodular goiter
• Lymphadenopathy due to other causes
• Metastasis from head and neck cancer

Types

• Papillary carcinoma
• Follicular carcinoma (including Hurthle cell variant)
• Medullar thyroid carcinoma (sporadic, familial, or multiple endocrine neoplasia 2)
• Anaplastic thyroid carcinoma
• Others: lymphoma, metastases (lung, breast, renal cell, melanoma)

• Thyroid nodules
• Goiter
• Neck mass