Is there a difference in the incidence of metastasis at diagnosis of lung cancer between smokers and non smokers

Background Since the degree of suspicion of lung cancer in nonsmokers is less would it lead to a delay in diagnosis? Or would etiologies other than smoking cause more aggressive, disseminated cancers? T he objective was to find out differences of incidence in metastasis at presentation in smokers and nonsmokers Methodology This prospective study was carried out in Teaching hospital kandy Sri Lanka for one year from January to December 2013.All patients who had histologicaly proven lung cancer were recruited. Their smoking history was obtained using an interviewer administered questionnaire. Staging was done by CT thorax, neck and upper abdomen, and in some cases with imaging of spine and brain. Patients with pleural effusions had pleural aspiration for cytology and pleural biopsy. Staging was done using TNM 7th revision .Smokers and nonsmokers were compared using chi square test. Results Total 71 Gender N % males 61 85.92 females 10 14.10 Mean age 62.8, Standard deviation +/- 11.26 View this table: Age distribution View this table: Incidence of metastasis at diagnosis by group Conclusion Nonsmokers have a statistically significant higher chance of having metastasis at the time of diagnosis than smokers.