Cancer among American-Samoans: site-specific incidence in California and Hawaii.

BACKGROUND: There is a paucity of data about cancer among American-Samoans, the largest Pacific Islander group after Hawaiians. This study provides the first data on the incidence and relative risk for all cancers among American-Samoans on the US mainland and in Hawaii.
METHODS: The University of Southern California Cancer Surveillance Program and the Hawaii Tumor Registry, two population-based cancer surveillance programmes, provided archival data on American-Samoans residing in Los Angeles Country. California and in Hawaii, respectively.
RESULTS: There were significant differences in the incidence and age-adjusted site-specific relative risk of cancers between American-Samoans, Hawaiians, and Anglos (non-Hispanic whites). In Hawaii, American-Samoans diagnosed with cancer compared with Hawaiians had a higher age-adjusted site-specific relative risk for cancers of the nasopharynx (especially males), liver, prostate, thyroid, and blood (especially females) and a lower relative risk for cancers of the colon, rectum (especially males), lung (especially females) and breast. Furthermore, compared with Anglos diagnosed with cancer in Hawaii, American-Samoans had a higher relative risk for cancers of the nasopharynx (especially males), stomach, liver, lung (especially males), corpus uteri, thyroid and blood, and a lower relative risk for cancers of the colon, skin, breast, testes, cervix uteri, bladder (especially males), and lymph nodes. A relatively similar profile of cancer distribution and relative risk was observed among American-Samoans and Anglos diagnosed with cancer in California.
CONCLUSIONS: The data provide baseline information which has important implications for future cancer control research and prevention in this population.