Abstract

Introduction: The mechanism of carcinogenesis of lung adenocarcinomas arising in smokers and non-smokers is distinct. Distinct tumorigenic mechanisms would imply differences in tumor biology, demographic characteristics, and survival. The aim of this study was to compare the patient characteristics and survival rates of current smokers and non-smokers with lung adenocarcinoma.

Material and Method: We studied 205 patients who were histopathologically diagnosed as having lung adenocarcinoma from 1990 to 2005. The 59 non-smoker patients were compared with the 146 current-smoker patients for demographic, clinical and radiological characteristics.

Results: The mean age (61.3 years vs. 58.1 years; p=0.036), female patient (79.7% vs. 4.8%; p<0.0001), comorbidities (32.2% vs. 14.4%; p=0.004), pleural effusion (40.7% vs. 19.2%; p=0.001) and diffuse spread (8.5% vs. 2.1%; p=0.032) were more frequent in the non – smoker patients than the other patients. However, good KPS (74.7 vs. 78.3; p=0.028), hemoptysis (15.3% vs. 32.9%; p=0.011), paraneoplastic syndrome complaints (11.9% vs. 32.2%; p=0.003), metastasis findings (16.9% vs. 39.0%; p=0.002), and mass (23.7% vs 42.5%; p= 0.012) were less frequent than in the other patients. Median survival was 7.1 months in non-smokers and 6.0 months in current smokers; overall survival was similar in both groups (Log Rank=0.09; p=0.76).

Conclusion: The epidemiological, clinical and radiological features of non – smoker patients differed from those of current smokers, but the prognosis was similar and depended on tumor stage and therapy. These findings suggest that further studies need to be done into cases suffering from adenocarcinoma for a better understanding of the nature and course of this disease.