Liu Ying, Kaneko Satoshi, Sobue Tomotaka
Cancer Information and Epidemiology Division, Research Institute, National Cancer Center, Tokyo 104-0045, Japan.
Int J Epidemiol. 2004 Aug;33(4):808-15. doi: 10.1093/ije/dyh053. Epub 2004 Mar 11.
This study was performed to estimate the incidence of gastric cancer by tumour location and to clarify whether the relative and absolute rates of gastric cancer in Japan changed between 1975 and 1989.
The stomach was anatomically divided into the upper, middle, and lower thirds. Age- and sex-specific incidences by tumour location were estimated by multiplying the age- and sex-specific national incidences of gastric cancer by the corresponding proportions of tumour location. We studied 171 721 cases of gastric cancer from the Gastric Cancer Registry of Japan.
Over 15 years, the proportion of tumours in the upper third of the stomach increased in men but did not change much in women. The proportion of tumours in the middle third of the stomach increased among both men and women while the proportion of tumours in the lower third of the stomach decreased among both men and women. The incidence of tumours in the upper third of the stomach showed an increasing trend among elderly men and women but not among young ones. The incidence of tumours in the lower third of the stomach decreased significantly among men and women of most age groups.
The present study added evidence of disparate trends in the incidence of gastric cancer by tumour location. The separate epidemiological features may indicate different aetiologies as well as changes in the degree of influence of these aetiologies.
本研究旨在按肿瘤位置估计胃癌发病率，并阐明1975年至1989年间日本胃癌的相对发病率和绝对发病率是否发生了变化。
将胃按解剖学分为上、中、下三分之一。通过将日本胃癌的年龄和性别特异性全国发病率乘以相应的肿瘤位置比例，估计按肿瘤位置划分的年龄和性别特异性发病率。我们研究了来自日本胃癌登记处的171721例胃癌病例。
在15年期间，胃上三分之一处肿瘤的比例在男性中增加，但在女性中变化不大。胃中三分之一处肿瘤的比例在男性和女性中均增加，而胃下三分之一处肿瘤的比例在男性和女性中均下降。胃上三分之一处肿瘤的发病率在老年男性和女性中呈上升趋势，但在年轻人中没有。胃下三分之一处肿瘤的发病率在大多数年龄组的男性和女性中均显著下降。
本研究补充了按肿瘤位置划分的胃癌发病率不同趋势的证据。不同的流行病学特征可能表明病因不同，以及这些病因影响程度的变化。
