J Cancer 2011; 2:52-61. doi:10.7150/jca.2.52
Smoking and Prognostic Factors in an Observational Setting in Patients with Advanced Non-Small Cell Lung Carcinoma
1. Chest Department, Changhua Christian Hospital, Changhua City, and the Institute of Medical and Molecular Toxicology, Chung Shan Medical University, Taichung City, Taiwan.
2. Department of Lung Cancer Chemotherapy, Bystra Hospital, Bystra, Poland.
3. Department of Chest Diseases, Izmir Chest Diseases Research Hospital, Izmir, Turkey.
4. Department of Pulmonology, Dankook University Hospital, Cheonan Choong Nam, Republic of Korea.
5. Department of Clinical Oncology, Faculty of Medicine, Cairo University, Cairo, and Eli Lilly, Egypt.
6. Chinese PLA Cancer Center, Nanjing Bayi Hospital, Nanjing, China.
7. Eli Lilly Regional Operations, Vienna, Austria.
8. Medical Department, Eli Lilly Turkey, Istanbul, Turkey.
Li CT, Marek M, Guclu SZ, Kim Y, Meshref M, Qin S, Kadziola Z, Krejcy K, Altug S. Smoking and Prognostic Factors in an Observational Setting in Patients with Advanced Non-Small Cell Lung Carcinoma. J Cancer 2011; 2:52-61. doi:10.7150/jca.2.52. Available from http://www.jcancer.org/v02p0052.htm
Background: This prospective observational study estimated the effect of prognostic factors, particularly continued smoking during therapy, on survival in advanced non-small cell lung cancer (NSCLC) patients receiving gemcitabine-platinum. Further, prognostic factors were used to build a survival model to improve prognosis prediction in naturalistic clinical settings.
Methods: Eligibility criteria included: Stage IIIB/IV NSCLC, no prior chemotherapy, and Eastern Cooperative Oncology Group (ECOG) performance status 0 or 1. A Cox regression model was constructed and validated by randomizing patients into two datasets (Construction [C]:Validation [V]; 3:1 ratio). Country, disease stage, hypercalcemia, “N” factor, weight reduction, performance status, and superior vena cava obstruction were pre-defined variables forced into the model. Continued smoking was tested with adjustment for these variables.
Results: One thousand two hundred and fourteen patients (C=891 and V=323) were enrolled. The final predictive model, established in the Construction dataset, identified four significant (p≤0.05) and independent predictors of survival, which were disease stage, performance status, gemcitabine-platinum regimen, and T-stage. Smoking during therapy was not significantly associated with survival (Hazard Ratio [95% CI]: 0.955 [0.572, 1.596], p=0.8618; versus never smokers).
Conclusions: Although continued smoking during therapy was not significantly associated with shorter survival, the model developed in this study forms an evidence-based approach to assessing prognosis in advanced stage NSCLC.
Keywords: smoking, observational, NSCLC, prognostic factors, predictive modeling.