|  | Cancer | Thyroid Cancer

Thyroid Cancer: Overview, Risk Factors, and Typical Age of Diagnosis

Epidemiology

Thyroid cancer is the most common endocrine malignancy. Incidence has risen (partly due to imaging detection). 3× more common in women. Peak diagnosis: ages 30–60. Lifetime risk: ~1.3%.

Major Histologic Types

  • Papillary (PTC): 80–85%. Excellent prognosis; often multifocal; spreads to cervical lymph nodes.
  • Follicular (FTC): 10–15%. Vascular invasion → hematogenous spread (lung, bone).
  • Medullary (MTC): 3–5%. C-cell origin; secretes calcitonin; 25% hereditary (RET mutations, MEN2).
  • Anaplastic (ATC): 1–2%. Aggressive, undifferentiated; elderly; very poor prognosis.

Risk Factors

  • Radiation exposure (childhood head/neck RT, nuclear fallout).
  • Iodine deficiency (follicular) or excess (papillary).
  • Genetic syndromes: MEN2, FAP, Cowden, Carney complex.
  • Family history (first-degree relative).

Presentation

Often asymptomatic thyroid nodule. May have hoarseness (RLN invasion), dysphagia, dyspnea, or cervical lymphadenopathy.

Diagnosis & Management

  • TSH, ultrasound, FNA biopsy (Bethesda classification).
  • Surgery: total thyroidectomy ± central/lateral neck dissection.
  • Radioactive iodine (RAI) ablation for intermediate/high-risk differentiated cancer.
  • TSH suppression with levothyroxine.
  • Surveillance: thyroglobulin, anti-Tg, ultrasound.
  • Advanced/metastatic: kinase inhibitors (lenvatinib, sorafenib), RET inhibitors (selpercatinib, pralsetinib), clinical trials.

Prognosis

Differentiated thyroid cancer (PTC/FTC) has >98% 20-year survival. MTC and ATC have guarded outcomes.

Thyroid Cancer - Related Articles