大肠癌发病的环境因素与遗传因素

以全人群大肠癌病例-对照研究数据(850名大肠癌新发病例及857名对照),详细分析了影响大肠癌发病的环境因素及遗传因素;并以该病例为先证者,调查了病例、对照两级两系三代亲属的大肠癌罹患情形。结果表明:①环境因素在大肠癌发病过程中起着决定性的作用;②与大肠癌先证者有血缘关系和共同生活经历的家族成员,具有比一般人群更高的患大肠癌超额危险性;而该家族集聚性、环境因素的决定作用约占83%,遗传易感性的影响约占17%。

Environmental and Inheritive Factors on Large Bowel Cancer

In order to clarify the influence of inherit and environmental factors on the large bowel cancer, a population-based case-control study involving 850 cases and 857 controls matched by age and sex, and a entailed family cancer history survey were carried out from September 1988 through August 1989. Multivariate analysis showed that less intake of crude fibre increased risk of the cancer whereas vegetables was negatively associated after controlling for some possible confounding factors. The intake of fat, protein and meat slightly raised the risk of the cancer. Univariate analysis showed that the history of large bowel cancer in first degree relatives had a remarkable risk (RR = 2.2, P less than 0.05), but adjusting environmental factors (especially dietary factors, e. g. fat, protein, crude fibre, calories ect.) the history had no close relationship with the cancer. The heritability of large bowel cancer was 16.78 +/- 6.20%.