Papillary thyroid carcinoma (PTC) is the most common thyroid malignancy. The most frequent molecular alteration in sporadic PTC is:

• A RAS mutation
• B BRAF V600E point mutation ✓
• C RET/PTC rearrangement
• D PAX8-PPARγ translocation

Explanation

BRAF V600E point mutation is the most frequent molecular alteration in sporadic adult PTC, occurring in approximately 40-60% of cases. It constitutively activates the MAPK/ERK pathway. BRAF V600E is associated with more aggressive behavior, higher risk of extrathyroidal extension, lymph node metastases, and possibly radioiodine refractoriness. RET/PTC rearrangements occur in ~10-20% of sporadic PTCs and are more common in radiation-induced PTCs (post-Chernobyl). RAS mutations and PAX8-PPARγ translocations are more characteristic of follicular thyroid carcinoma.

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

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.