A 60-year-old man presents with a rapidly enlarging painless neck mass, stridor, and dysphagia over 6 weeks. FNA shows highly pleomorphic cells with giant multinucleated cells and spindle cells. What is the most likely diagnosis and its expected 1-year survival?

• A Poorly differentiated thyroid carcinoma; approximately 50%
• B Medullary thyroid carcinoma; approximately 85%
• C Primary thyroid lymphoma; approximately 80%
• D Anaplastic thyroid carcinoma; approximately 5–10% ✓

Explanation

Anaplastic (undifferentiated) thyroid carcinoma presents with rapid neck growth, local invasion (stridor, dysphagia) and is cytologically characterised by pleomorphic giant cells, spindle cells, and high mitotic activity. It is universally Stage IVA–IVC at diagnosis and carries a median survival of 3–5 months with a 1-year survival of <10%. Medullary and well-differentiated carcinomas have far better outcomes. Primary thyroid lymphoma occurs in Hashimoto's background and responds to chemoradiation.

Reference: Bailey & Love's Short Practice of Surgery, 27th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.