Prognostic factors in patients with stage IV non-small cell lung cancer

Abstract

Objective: To investigate the prognostic factors for stage IV non-small cell lung cancer (NSCLC) with distant metastasis and establish a reliable model of clinical prognostic index. Methods: From January 1990 to April 2005, 313 primary NSCLC patients with metastasis, who had been treated in Shanghai Chest Hospital, were reviewed. Survival time was estimated according to the Kaplan-Meier method. Cox proportional hazard regression model was used for multivariate analysis. Results: Among the 313 cases of non-small cell lung cancer (NSCLC) at stage IV, there were 218 and 95 patients with metastasis to single and different organs, respectively. The overall median survival time for all 313 cases of NSCLC patients was 10.8 (9.00, 12.30) months and the overall 1-, 2-, 3-, 4-and 5-year survival rate was 45%, 18%, 12%, 4% and 0%. There were 63, 174, 127, 36, 18, 11 and 5 patients with metastasis to brain (20.13%), bone (55.59%), lung (40.58%), liver (11.50%), adrenal gland (5.75%), subcutaneous (3.51%) and others, respectively. The survival time was shortest in subcutaneous metastasis (4.6 months), and liver 7.0 months, brain 8.0 months, adrenal gland 8.6 months, bone 10.6 months, lung 11.8 months. Kaplan-Meier estimation showed that patients anatomic typing, KPS, numbers of organ with metastasis, appetite, liver, adrenal gland and subcutaneous metastasis, body weight loss, smoking, index of smoking, chemotherapy, cycles of chemotherapy were the predictors of survival. Multivariate analysis showed survival statistically significant correlation with anatomic typing, KPS, appetite, liver and subcutaneous metastasis, body weight loss, cycles of chemotherapy. The relative risk (RR) was 1.51, 1.97, 1.55, 1.67, 2.56, and 2.56 respectively. Conclusion: Survival time decreases distinctly in patients who had distant metastasis to more than two different organs (P<0.01). Bone is the commonest organ for distant metastasis in lung cancer. The prognosis is poor when lung cancer appears subcutaneous metastasis and liver metastasis. Independent prognostic factors in patient with stage IV non-small cell lung cancer were liver and subcutaneous metastasis, anatomic typing, KPS, appetite, body weight loss, cycles of chemotherapy.