Background: We previously reported that Asian ethnicity is a favorable prognostic factor for overall survival (OS) in non-small cell lung cancer (NSCLC) patients independent of smoking status. However, Asian ethnicity represents a diverse and heterogeneous population. In this report, we compared the clinicopathologic characteristics of Asian American NSCLC patient subgroups by smoking status.
Methods: Clinicopathologic characteristics of the five major Asian American NSCLC patient subgroups diagnosed between 1991 and 2005 from three Southern California counties were analyzed. Prognostic factors for OS were evaluated by Cox multivariate analysis.
Results: One thousand one hundred twenty-four NSCLC patients were analyzed: Filipino American (37.0%), Vietnamese American (32.8%), Japanese American (11.8%), Chinese American (11.7%), and Korean American (6.7%). A total of 25.7% of these patients were never smokers. With the exception of Japanese American, most of Asian American were native born. Median age of never smokers was marginally younger than ever smokers (66 years versus 68 years, respectively, p = 0.0507). The proportion of never smokers who were women was 72.7% and ranged from the lowest among Korean American women (66.7%) to the highest among Japanese American women (84.2%). Among female patients, Vietnamese American patients had the highest proportion of being never smokers (65.5%). Significantly more never smokers (60.9%) than ever smokers (47.9%) presented with stage 4 disease. There was no statistical significant difference in OS between never smokers and ever smokers (11 versus 10 months; p = 0.3040). Tumor-related factors (stage and histologic differentiation) and treatment (surgery and chemotherapy) were independent prognostic factors for survival.
Conclusions: We found no statistical significant difference in clinicopathologic features or survival outcome between individual Asian American subgroup when analyzed according to smoking status.