The investigators performed a multicenter, open trial of using TS gene polymorphism to predict advanced lung adenocarcinoma effect to pemetrexed combined with cisplatin regiment as first-line treatment.

1. Main eligibility criteria were histologic or cytologic proof of advanced non-small-cell lung cancer (NSCLC) primary treatment, normal organ function, and Eastern Cooperative Oncology Group performance status 0 to 2.
2. All Patients were delivered to pemetrexed 500 mg/m2 and cisplatin 75 mg/m2 for not less than 4 cycle, administered intravenously every 3 weeks. Response assessment was performed every 6 weeks; toxicity assessment was performed every 3 weeks.
3. Primary end point was time to progression (TTP); secondary end points were objective response rate (ORR), overall survival (OS), and toxicity.
4. The study was designed to evaluate TS(thymidylate synthase) gene polymorphism as a predictor for advanced lung adenocarcinoma effect to pemetrexed combined with cisplatin regiment as first-line treatment.
5. Polymorphisms of thymidylate synthase were investigated in peripheral WBC（white blood cell）of all patients.

Inclusion Criteria:

• histologic or cytologic proof of advanced lung adenocarcinoma
• primary treatment
• normal organ function
• Eastern Cooperative Oncology Group performance status 0 to 2

Exclusion Criteria:

• Symptomatic patients with brain metastases
• Major organ dysfunction and severe heart disease