Maskarinec Gertraud, Noh Jihae J
Cancer Research Center of Hawaii, Honolulu, Hawaii 96813, USA.
Ethn Dis. 2004 Summer;14(3):431-9.
This analysis compared cancer incidence trends among Japanese in Japan, and Japanese and Caucasians in Hawaii, between 1960 and 1997, and estimated the impact of migration on the incidence of different cancers.
Incidence information was obtained from 8 volumes of Cancer Incidence in Five Continents. The migration effect was estimated from the areas under the incidence curves as the ratio of the geographic and the ethnic difference in cumulative cancer incidence.
Among the 5 more common cancers, the migrant effect was strongest for colon and stomach cancers, prostate and breast cancers were affected to a lesser degree, and lung cancer risk differed little between Japanese in Japan and Hawaii. Migration led to lower risk of stomach, esophageal, pancreatic, liver, and cervical cancers, but to higher rates for all other cancers. The large variation in time for migrants to adopt the host population's cancer risk suggests that risk factors have organ-specific effects, or operate at different times in life. Although the available incidence rates are limited by under-reporting and early detection efforts, mortality rates confirm the significant differences in cancer risk.
The persistent difference in cancer incidence several generations after migration supports the idea that living in the host country is not, alone, sufficient to modify cancer risk for all cancer sites to the level of the host population. Although the migration effect can be partially explained by known etiologic factors, a large proportion of the changing risk remains unexplained.
本分析比较了1960年至1997年间日本国内日本人、夏威夷的日本人和高加索人的癌症发病率趋势，并估计了移民对不同癌症发病率的影响。
发病率信息取自8卷《五大洲癌症发病率》。通过发病率曲线下的面积估计移民效应，即累积癌症发病率的地理差异与种族差异之比。
在5种较常见的癌症中，结肠癌和胃癌的移民效应最强，前列腺癌和乳腺癌受到的影响较小，日本国内的日本人和夏威夷的日本人患肺癌的风险差异不大。移民导致胃癌、食管癌、胰腺癌、肝癌和宫颈癌的风险降低，但其他所有癌症的发病率升高。移民采用宿主人群癌症风险的时间差异很大，这表明风险因素具有器官特异性效应，或在生命中的不同时间起作用。尽管现有的发病率受到报告不足和早期检测工作的限制，但死亡率证实了癌症风险的显著差异。
移民几代后癌症发病率持续存在差异，这支持了这样一种观点，即仅生活在宿主国家不足以将所有癌症部位的癌症风险改变到宿主人群的水平。尽管移民效应可以部分由已知的病因因素解释，但很大一部分风险变化仍无法解释。
