Asian-Americans show significantly higher survival for gastric cancer than patients from other ethnic or racial groups, according to research from City of Hope.
Data from the Los Angeles County Cancer Surveillance Program show that patients of Asian descent with gastric adenocarcinoma survive nearly twice as long after diagnosis as Latinos; blacks and whites do worst.
Brian Mailey, M.D., a research fellow in City of Hope’s Division of General Oncologic Surgery, presented the findings at the 2009 American Society of Clinical Oncology Gastrointestinal Cancers Symposium in San Francisco on Jan. 15. Mailey earned a Merit Award for the oral presentation.
|Joseph Kim (Photo by Walter Urie)|
The study is the largest ever on racial disparities in gastric cancer, or cancer of the stomach.
“We looked at all patients in the county from 1988 to 2006 with gastric cancer, and no matter what the extent of disease or treatment, Asians did best,” said Joseph Kim, M.D., assistant professor in the Department of Surgery and senior author on the study.
Kim and his colleagues sought to explore potential disparities in gastric cancer outcomes because of differences in survival internationally from gastric cancer, the second-leading cancer worldwide and one of the top five causes of cancer death. Patients in Eastern nations are more than twice as likely to live for at least five years after treatment as those in Western nations. Surgeons in Asian nations have attributed the success to their extensive surgeries, but other studies have found no link between surgical technique and outcome.
The City of Hope research team analyzed more than 13,500 cases of gastric cancer in Los Angeles County, an ideal site for study because of its diverse population. Asian-Americans comprise 10 percent of the county’s population and about 25 percent of the gastric cancer patients studied, since the disease is more prevalent among those of Asian descent due to factors including dietary habits (consumption of smoked, pickled and salted foods).
Survival for patients with gastric cancer in all stages broke down this way:
- About 28 percent of Asian-Americans survived for five years; typical survival was 15.8 months.
- Latinos had a five-year survival rate of 16 percent and survived a median 8.6 months.
- Among whites, 13.5 percent survived five years with a median 8.1-month survival.
- Blacks had a median survival of 7.7 months and five-year survival rate of 12 percent.
Whether gastric cancer was discovered early or late — and regardless of how it was treated or where it was located in the stomach — Asians still lived longer.
“It’s not really clear why these differences exist, but it’s unlikely to be related to surgical technique,” Kim said. “We suspect there may be differences in tumor biology among the groups.”
Other City of Hope researchers collaborating on the study included Smita Bhatia, M.D., M.P.H., and Canlan Sun, M.D., Ph.D., of the Department of Population Sciences, and Avo Artinyan, M.D., Christie Prendergast, M.D., Alessio Pigazzi, M.D., and Joshua D.I. Ellenhorn, M.D., of the Department of Surgery.