New perspectives on metastatic patterns in lung cancer: The M. D. Anderson thoracic medical oncology database

Abstract

7630 Background: We previously reported a retrospective study suggesting that sites of metastatic disease characterize distinct prognostic groups with non-small cell lung cancer (NSCLC) (ASCO 2005 Abstract No: 7197). To confirm these observations, we prospectively evaluated pts with newly diagnosed NSCLC to correlate extent of disease with survival. Methods: We developed a prospective comprehensive database of 2,487 pts registered in the Thoracic Medical Oncology Department from 9/1/2004 - 8/31/2006, with up to 845 days follow-up. 694 were untreated stage IV NSCLC pts with data for ECOG performance status (PS), TNM staging, histology, identification of all metastatic sites, and survival. Results: Bone was the most common metastatic site, affecting 280 pts, 114 having bone only metastases (280/114). Similarly, the following results were found for lung (261/137), brain (143/46), adrenal (112/36), and liver (98/31). PS = 0 (101), PS = 1 (329), PS = 2 (103), PS = 3 (74), PS = 4 (10), PS = unknown (77). As of January 2007, median survival for the group was 8 months. By the Cox regression model, statistically significant effects on overall survival were seen for gender, smoking status, age, performance status, and number of metastases. The following hazard ratios [with 95% CI] of death were seen for males vs. females 1.41 ([1.13, 1.75], p = 0.0025), former smokers vs. non-smokers 1.66 ([1.18, 2.31], p = 0.0032), active smokers vs. non-smokers 1.79 ([1.21, 2.64], p = 0.0036), for one year increase in age 1.02 ([1.00, 1.03], p = 0.0046), for one unit increase in performance status 1.63 ([1.45, 1.82], p < 0.0001) and for one unit increase in number of metastases 1.48 ([1.32, 1.66], p < 0.0001). Pts with one metastatic site had superior survival over pts with more sites. Six of 10 metastatic sites were found to have significant independent effects on overall survival, based on log-rank test. Conclusions: Number and sites of metastases were strong independent determinants of survival in NSCLC. Furthermore, our work suggests marked heterogeneity of metastatic patterns at presentation. Pts with fewer metastatic sites demonstrate better survival. Future targeted therapy protocols should stratify according to metastatic sites to better analyze patterns of failure and outcomes. No significant financial relationships to disclose.