[A Case Report on Successful Third Challenge to the Pemetrexed-based Regimen for Advanced Non-small Cell Lung Cancer]

Non-small cell lung cancer (NSCLC) accounts for about 85% of lung cancer, with a 5-year survival rate of less than 15%-19%, and more than 80% of the patients with lung cancer have progressed to advanced stage (Stage IIIb-IV) when they are clearly diagnosed. The comprehensive treatment mainly based on chemotherapy as the primary form is now considered as the major therapy method for advanced NSCLC without actionable driver gene mutations. Pemetrexed plus platinum doublet as well as single-agent pemetrexed are respectively the first-line major regimens recommended by guidelines and the second-line optional regimens. Yet the third-line treatment or beyond in advanced NSCLC is not evidence-based but conducted based on patients' previous medications, which is one of the most commonly used clinical methods. As pemetrexed is a multi-target chemotherapy drug with high efficiency but low toxicity, pemetrexed re-challenge strategy in advanced NSCLC is also a reasonable choice. We report one effective individual case that adopted pemetrexed re-challenge strategy in advanced NSCLC for three times, and at the same time conduct the relevant literature review.