Lung cancer is the No. cause of cancer death in Taiwan. Yet most of lung cancer are diagnosed at late stage, not amenable to surgical resection. With the introduction of new targeted agents, such as EGFR tyrosine kinase inhibitors and the identification of EGFR mutations, lung cancer management has markedly changed in recent years. However, these new agents are costly and their payment is restricted in certain situations defined National Insurance Agency. Therefore, using databases from National Insurance Agency might not be able to reflect the exact impact on pharmacoeconomics. In this study, the investigators will analyze the data from a tertiary medical center, where all the costs including insurance reimbursement, co-payment, and payment not covered by insurance. The investigators will also compare with the investigators results with national database to analyze the cost benefit of these new agents on lung cancer.

Inclusion Criteria:

• lung cancer patients in WanFang Hospital

Exclusion Criteria:

• non

lung cancer patients in WanFang Hospital