A 44-year-old woman who underwent hemithyroidectomy for a 3 cm minimally invasive follicular carcinoma returns three years later with a pathological fracture of the femur. Biopsy of the bone lesion shows well-differentiated follicular structures positive for thyroglobulin. The characteristic route of distant spread of follicular thyroid carcinoma is:

• A Lymphatic spread to cervical nodes first
• B Haematogenous dissemination to bone and lung ✓
• C Direct extension into trachea and oesophagus
• D Transcoelomic peritoneal seeding

Explanation

Unlike papillary carcinoma, which spreads predominantly through cervical lymphatics, follicular carcinoma characteristically disseminates haematogenously, producing solitary or multiple metastases in bone and lung that can retain well-differentiated follicular architecture and thyroglobulin expression years after the primary. This behaviour explains late skeletal presentations. Direct local extension and transcoelomic spread are not typical patterns for this tumour.

Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.