Gefitinib is a selective small molecule epidermal growth factor receptors (EGFR) tyrosine kinase inhibitors (EGFR-TKI), it's curative effect on non-small cell lung cancer (NSCLC) has been confirmed by a number of prospective clinical trials. The researches aim to analysis whether bone metastasis could affect the survival of NSCLC patients who were effective in Gefitinib treatment over 6 months.

The epidermal growth factor receptors (EGFRs) have inhibitory effects on cell apoptosis, cell growth, angiogenesis and metastasis of tumor cell. The advent of EGFR-TKI significantly improved the clinical efficacy and safety of non-small cell lung cancer (NSCLC) treatment. Compelling study also demonstrate Gefitinib may be effective in the treatment of bone metastases. For NSCLC patients who were effective in EGFR-TKI treatment, whether bone metastasis would shorten the survival time of the patients or reduce the quality of life of patients is worth studying. The researches aim to analysis whether bone metastasis could affect the survival of NSCLC patients who were effective in Gefitinib treatment over 6 months.

Inclusion Criteria:

1. histological and (or) cytological diagnosed NSCLC patients.
2. patient was effective in Gefitinib treatment more than 6 months.
3. whether patient received chemotherapy and other treatment is not restricted.
4. whether patient was detected for EGFR gene mutation was not restricted.

Exclusion Criteria:

1. patient with small cell lung cancer.
2. patient without cytology or histopathology diagnosis results.
3. patient with bone metastases cannot rule out other reasons such as inflammation or trauma.
4. patient with poor treatment compliance.
5. patient with incomplete data.

The patients' data were not allowed to been using outside this research.