Lung Cancer in Asian Immigrants: More-Advanced Disease, Less-Favorable Outcomes
Abstract & Commentary
Synopsis: In a 5-year retrospective analysis of lung cancer in Asian immigrants living in Boston and seen at the New England Medical Center, more-advanced disease and shorter survival was observed when compared to non-Asian, and age- and gender-matched controls.
Source: Finlay GA, et al. Chest. 2002;122:1938-1943.
In Boston, like many urban locations throughout the United States, there has been a fairly dramatic increase in the Asian population. To test a clinical hypothesis that Asian immigrants presented with more-advanced disease and had shorter lung cancer survival, Finlay and colleagues at New England Medical Center performed a 5-year retrospective case-control study (1992-1996) in which 42 Asian immigrants with lung cancer diagnosed over the study period were matched for age and sex with 42 non-Asian control subjects. The Asians presented more frequently with advanced stage (stage III or IV) disease and less frequently with early stage disease (stage I or II) than the non-Asian control group (P < 0.05). Asians were also more likely to present with hemoptysis or constitutional symptoms (P < 0.01) and had a longer duration of symptoms prior to presentation (P < 0.01). The incidence of large-cell carcinoma was higher in Asians (P < 0.05). Diagnostic procedures and length of time from diagnosis to treatment were not significantly different. The treatment of stage I and II disease did not differ, but for the more advanced stages, Asians were more likely to receive radiation therapy alone and not combination therapy, compared to non-Asian controls (P < 0.05). The median 2-year survival was significantly reduced in Asians (7 months) compared with non-Asians (15 months) (P < 0.001). Thus, in this retrospective review, the clinical hypothesis that Asian immigrants present with more advanced disease and have shorter survival was proven true.
Comment by William B. Ershler, MD
It is impossible to tell from the current report whether there is an inherently more aggressive nature of lung cancer in Asian immigrants, although this might be discernible in a larger study, from which survival in stage-matched patients could be assessed. However, the increased number with large-cell histology would suggest that certain genetic or environmental factors may explain some of the differences observed in the Asian patients. Certainly, social factors may be of equal or even greater importance in explaining the findings. For any of a number of reasons, the Asian patients included in this survey delayed seeking medical attention (ie, had symptoms for a longer time), and at the time of diagnosis were found to have more advanced disease. Fewer presented with early stage disease and, not surprisingly, survival was shorter.
The data presented were not dissimilar from what has been observed with African Americans1-3 demonstrating more advanced disease at presentation, fewer curative resections, and shorter survival.
Social factors that may be involved in the delay in diagnosis include language barriers, a reluctance to be treated with Western medicine, or a lack of financial resources to gain access to care. Certainly, other factors are involved as well. Whatever the explanation, clinicians need to be aware that lung cancer in Asian immigrants will become increasingly apparent with our changing demography, particularly in urban populations, and the persistent use of cigarettes throughout this culture. Furthermore, we need to be especially vigilant in light of the fact that such patients present with more advanced disease. It is likely that for the near future, our best chance for influencing this unfavorable picture would be a community-based educational program that would encourage smoking cessation and earlier diagnostic interventions.
Dr. Ershler, INOVA Fairfax Hospital Cancer Center, Fairfax, VA, is Editor of Clinical Oncology Alert and Director of the Institute for Advanced Studies in Aging, Washington, DC.
1. Landis S, et al. CA Cancer J Clin. 1998;48:6-29.
2. Greenwald HP, et al. Am J Public Health. 1998;88:1681-1684.
3. Bach PB, et al. N Engl J Med. 1999;341:1198-1205.