Maintenance therapy has been considered as an important component to prolong survival in patients with advanced Nonsquamous Non-small Cell Lung Cancer (NSCLC). Previous studies have confirmed that pemetrexed is one of the effective drugs in improving progression-free survival for stage IIIb-IV nonsquamous non-small cell lung cancer. With the periodic deliveries of pemetrexed, however,the functioning status and immune system may get worse, which subsequently has an negative impact on patient's quality-of-life. Immunotherapy with autologous cytokine-induced killer (CIK) cells can activate the antitumor defense mechanism through stimulating immune response and altering the interaction between tumor and its host. This effect may result in improved tumor control and survival, as well as a better quality of life. To test the hypothesis, a randomised controlled study was conducted to compare CIK cells with pemetrexed as maintenance therapy for stage IIIb-IV nonsquamous non-small cell lung cancer.

Inclusion Criteria:

• Histologically or cytologically proven nonsquamous non-small cell lung cancer
• Stage IIIb-IV, according to AJCC 2010 Staging System
• Disease measurable
• Patients are currently receiving two-drug chemotherapy regimen containing a platinum-based drug as first-line therapy
• No chemotherapy or radiotherapy prior to first-line therapy
• Age between 18-75
• Performance status <2
• No congestive heart failure, severe arrhythmia,and coronal atherosclerosis heart disease
• No uncontrolled metabolic disease, infection, and neurological disorders
• No other malignancies
• Signed study-specific consent form prior to study entry

Exclusion Criteria:

• Patients are currently receiving radiotherapy or any chemotherapy regimen other than two-drug containing a platinum-based drug as first-line therapy
• Pregnant or lactating women
• Patient having hepatitis B virus infection, active tuberculosis, or other infectious diseases