OBJECTIVES: Lung cancer is the most frequent cause of cancer death with cigarette smoking being the number one risk factor. Nearly 90% of lung cancer deaths are attributable to smoking. Smoking in patients diagnosed with lung cancer decreases the rate of survival, quality of life, and reduces the effectiveness of medical treatment in these patients. One of the ways to stop smoking is through the use of smoking cessation agents. The purpose of this study is to explore the prevalence of smoking among lung cancer patients and patient reported use of smoking cessation agents using a national dataset. METHODS: A retrospective study was done to identify lung cancer patients (ICD-9 = 162) who smoke and those who use smoking cessation agents from 2006-2010 using Medical Expenditure Panel Survey (MEPS) data. Number of patients who smoke and those who use smoking cessation agents were described. RESULTS: Data from five years identified nearly 260 lung cancer patients. Out of these, 48 patients, accounting for 18.4% prevalence, reported smoking even after diagnosed with lung cancer. Percentage of female smokers was 58.33% while that of males was 41.66%. Medication history for these patients revealed a very low proportion, (i.e. 6/48 or 12.5%) reported using any form of smoking cessation agents. CONCLUSIONS: It is evident from the results that significant numbers of patients continue smoking even after diagnosis. This might be an underestimated number as this was patient reported information. There may be more patients that have not reported smoking because of social dogma. This shows that the non-medical efforts to quit smoking might have been unsuccessful. Also, the use of smoking cessation agents among these patients is extremely low. This is an alarming matter and future research should focus on identifying barriers to use of smoking cessation agents and approaches to address those barriers.