A 55-year-old lifetime non-smoker woman has a peripheral lung adenocarcinoma with EGFR exon 19 deletion. This mutation confers sensitivity to which targeted therapy?

• A Crizotinib (ALK inhibitor)
• B Pembrolizumab (anti-PD-1)
• C Bevacizumab (anti-VEGF)
• D Erlotinib/gefitinib/osimertinib (EGFR tyrosine kinase inhibitors) ✓

Explanation

EGFR exon 19 deletions (and exon 21 L858R point mutations) are activating mutations in the tyrosine kinase domain that confer sensitivity to EGFR tyrosine kinase inhibitors — first generation (erlotinib, gefitinib), second generation (afatinib), and third generation (osimertinib, which also covers T790M resistance mutations). EGFR mutations are more common in women, non-smokers, and Asians. Crizotinib targets ALK/ROS1/MET rearrangements.

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

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.