American Board of Internal Medicine (ABIM) Certification Practice Exam

What is a common agent used for patients with an EGFR mutation in lung adenocarcinoma?

1. Crizotinib

2. Pemetrexed

3. Erlotinib

4. Doxorubicin

The correct answer is: Erlotinib

Erlotinib is commonly used for patients with an epidermal growth factor receptor (EGFR) mutation in lung adenocarcinoma because it is a targeted therapy specifically designed to inhibit the signaling pathways associated with these mutations. Lung adenocarcinoma with EGFR mutations often leads to increased tumor growth and proliferation driven by the EGFR signaling pathway. By blocking this pathway, erlotinib can effectively reduce tumor size and slow disease progression. In contrast, crizotinib is primarily indicated for patients with anaplastic lymphoma kinase (ALK) rearrangements and is not effective in targeting EGFR mutations specifically. Pemetrexed is a chemotherapy agent used for non-squamous non-small cell lung cancer but does not specifically target EGFR mutations. Doxorubicin is a chemotherapeutic agent primarily associated with other cancers, like breast cancer and lymphoma, and lacks the specificity for EGFR alterations found in lung cancer. Thus, erlotinib stands out as the appropriate treatment for patients with this particular mutation in lung adenocarcinoma.