Roxanne Nelson, Medscape, September 30, 2016
Asian Americans have overall lower cancer mortality rates as compared with non-Hispanic whites (NHWs), but certain exceptions point to differences in biological or lifestyle risk factors. For example, stomach and liver cancer mortality are very high in several Asian American groups.
These findings come from the first report to comprehensively document trends and patterns of cancer mortality among six major Asian American ethnic groups. The report was published in the October issue of Cancer Epidemiology, Biomarkers & Prevention.
The authors suggest that cancer prevention and screening efforts geared to specific ethnic groups may be beneficial.
Two cancers found at a much higher rate among Asian Americans than among NHWs are stomach and liver cancer, the report notes.
Death from stomach cancer accounted for about 10% to 15% of cancer mortality among ethnic Koreans and approximately 5% to 10% of cancer related mortality among Chinese, Japanese, and Vietnamese.
In contrast, stomach cancer accounted for less than 2% of all cancer deaths among NHWs.
Death due to liver cancer was also generally much higher in the Asian American population. It accounted for 22% of cancer deaths in Vietnamese males, 12% of Chinese males, and 10% of Vietnamese females.
Again, in contrast, liver cancer was responsible for less than 2.5% of cancer related deaths in NHWs.
“We know that certain cancers, such as liver cancer, that are related to infections such as hepatitis B are more common in China,” said lead author, Latha P. Palaniappan, MD, MS, a clinical professor of medicine at Stanford University School of Medicine in California.
“Liver cancer is also more common in Chinese Americans,” she told Medscape Medical News. “We have a publication under review that examines nativity status–foreign-born vs US born–and we do see higher rates of some cancers among foreign-born populations, possibly due to higher-risk exposures to certain viruses in the country of origin.”
For their study, the authors obtained data on 85,616 cancer-related deaths from 2003 to 2011 from the National Center for Health Statistics. They examined cancer-related mortality for Asian Indians, Chinese, Filipinos, Japanese, Koreans, and Vietnamese and compared it with mortality for NHWs as the reference population.
When looking at the major cancer types, they found that lung cancer was the leading cause of cancer-related death for men in all Asian American groups, as well as for Chinese, Japanese, and Vietnamese women. Among Filipino and Chinese men, lung cancer accounted for approximately 30% of all cancer-related deaths.
But the overall mortality burden for male lung cancer in most Asian American groups was about half of that seen in NHWs; in females, it was half to one third. This was particularly true for Asian Indians of both sexes, who had markedly lower lung cancer mortality rates than both NHWs and all other Asian ethnic groups.
Given the differences in cancer mortality, Dr Palaniappan suggested that diverse Asian subpopulations should have targeted cancer screening guidelines tailored to the unique cancer risks in their communities.