Thyroid Nodules: Types, Cancer Risk & When to Worry

Thyroid nodules are common; most are benign. Evaluation by a healthcare professional is essential.

Nodule Categories & Risk

• Benign nodules (colloid, cysts) – ~90-95%; usually asymptomatic, monitor with ultrasound.
• Follicular neoplasms – indeterminate; 15-30% malignant; surgery often needed for diagnosis.
• Papillary thyroid carcinoma – most common thyroid cancer (~80%); slow-growing, excellent prognosis.
• Medullary thyroid carcinoma – from parafollicular C-cells; may be sporadic or genetic (MEN syndromes).
• Anaplastic thyroid carcinoma – rare, aggressive, poor prognosis.
• Hashimoto's thyroiditis – autoimmune; causes goiter/nodules and hypothyroidism.

Red Flags for Prompt Evaluation

• Rapid growth, firm/fixed mass
• Hoarseness, dysphagia, persistent cough
• Lymphadenopathy

Fine-needle aspiration (FNA) biopsy guided by ultrasound is the standard diagnostic step.