We know that lung cancer isn't one disease. Lung cancer in men differs from lung cancer in women. Lung cancer in non-smokers differs from lung cancer in people who smoke. And, it appears that lung cancer in Asians has unique characteristics as well.
Why is that important?
As the treatment for lung cancer improves with medications directed at specific mutations (abnormal changes in cancer cells), it's important to know what cancers might be expected to have those mutations. Understanding these differences lays the groundwork for tailoring treatment to the individual rather than the masses, something called personalized medicine.
It can sound complicated, but we look at individual differences in people every day. A shoe salesman doesn't attempt to sell bowling shoes to a runner, nor does she try to sell rock climbing shoes to a golfer. A general purpose shoe might offer some protection from the elements, but the results may not be as good (think running 26 miles in bowling shoes). I know that's overly simplistic but bare with me.
On a population basis we know that lung cancer in Asians differs (on the whole) from lung cancers in Caucasians. In this group of people lung cancer often occurs at an earlier age, is more common in people who have never smoked, and has a better overall prognosis.
So researchers decided to look at the molecular differences in lung cancers among Asians. They found that East Asians with lung cancer:
- Are more likely to have a mutation in epidermal growth factor receptor (EGFR) - (30% of East Asians vs 7% of Caucasions). This mutation is more common in non-smokers with adenocarcinoma
- Are less likely to have a mutation in Kras - (10% of East Asians vs 18% of Caucasians). This mutation is more common in smokers with adenocarcinoma
What does this mean?
Many of the new medications for lung cancer are designed to target these mutations. For example, the medication Tarceva (erlotinib) is an inhibitor of EGRF, the mutation above that is more common in non-smokers. In the real world Asians are more likely to respond to this category of medication.
What does this mean for you if you aren't of Asian decent? The important point regardless of your ethnic heritage, is that all lung cancers are different. The statistics you have been quoted may not be relevant to you. But most importantly, it is a reminder that research on lung cancer brings hope that through clinical trials, we will find treatments specific to individuals that will make a difference in a disease that, unfortunately, has a survival rate we should be ashamed of in the 21st century.
Photo: National Cancer Institute, Rhoda Baer (photographer)
Sources:
Ahn, M. et al. Korean ethnicity as compared with white ethnicity is an independent favorable prognostic factor for overall survival in non-small cell lung cancer before and after the oral epidermal growth factor receptor tyrosine kinase inhibitor era. Journal of Thoracic Oncology. 2010. 5(8):1185-96.
Kawaquchi, T.et al. Japanese ethnicity compared with Caucasian ethnicity and never-smoking are independent favorable prognostic factors for overall survival in non-small cell lung cancer: a collaborative epidemiological study of the National Hospital Organization Study Group for Lung Cancer (NHSGLC) in Japan and a Southern California Regional Cancer Registry databases. Journal of Thoracic Oncology. 2010. 5(7):1001-10.
Soo, R. et al. Ethnic Differences in Survival Outcome in Patients with Advanced Stage Non-small Cell Lung Cancer: Results of a Meta-Analysis of Randomized Controlled Trials. Journal of Thoracic Oncology. 2011 Apr 28. (Epub ahead of print)>
Zhou, W. and D. Christiani. East meets West: ethnic differences in epidemiology and clinical behaviors of lung cancer between East Asians and Caucasians. China Journal of Cancer. 2011. 30(5):287-92.
