Kodama M, Kodama T, Kodama M
Kodama Research Institute of Preventive Medicine, Nagoya, Japan.
Anticancer Res. 1991 Sep-Oct;11(5):1895-904.
The present study attempted to get insight into the etiology of bladder cancer by investigating the relation of this neoplasia to other 4 cancers as regards their risk variations in time and space. The results obtained are as follows: 1) Caucasians in Western countries were more inclined to develop bladder cancer than other ethnic groups, as compared among 43 population units of the world in terms of the age-adjusted incidence rate (AAIR). 2) In the same 43 comparison sets, male populations were always higher than female populations in their bladder cancer risks. The male to female ratio for the majority of the populations ranged from 3 to 4. In some population units, the ratios were much higher. In both male and female populations, the cancer risk increased with age. 3) Bladder cancer incidence in the world has been rising during the past 20 years, as detected in the follow-up study of 16 population units. 4) A negative linear relationship was detected for both sexes between bladder cancer and stomach cancer (non-Western type) regarding their log-transformed AAIRs, as calculated with data of the same 16 population units from 1960 through 1980. The same calculation with the esophagus cancer-bladder cancer pair gave marginally negative and no correlations respectively in the male and female populations. A positive linear relationship was detected in the comparison of bladder cancer with 2 Western type cancers (cancers of the colon and lung). 5) Japanese immigrants to the US were just in between Whites in the US (high-risk populations) and native Japanese (low-risk populations) in their bladder cancer risks. The same Japanese immigrants were again just in between Whites in the US (low-risk populations) and native Japanese (high-risk populations) in their stomach cancer risks. In conclusion, bladder cancer is a Western type cancer with sex and age discriminations in its occurrence. The cancer risk also varies depending on the life style of a population (environment dependent). The results obtained are discussed from the point of view of endocrinological oncology.
本研究试图通过调查膀胱癌与其他4种癌症在时间和空间上的风险变化关系，深入了解膀胱癌的病因。所得结果如下：1）就年龄调整发病率（AAIR）而言，在世界43个人口单位的比较中，西方国家的白种人比其他种族更易患膀胱癌。2）在同样的43个比较组中，男性人群患膀胱癌的风险总是高于女性人群。大多数人群的男女比例在3至4之间。在一些人口单位，该比例更高。在男性和女性人群中，癌症风险均随年龄增长而增加。3）在对16个人口单位的随访研究中发现，过去20年全球膀胱癌发病率一直在上升。4）根据1960年至1980年来自同样16个人口单位的数据计算，膀胱癌与胃癌（非西方类型）的对数转换AAIR之间，男女均呈负线性关系。食管癌与膀胱癌的配对计算结果显示，男性人群呈微弱负相关，女性人群无相关性。膀胱癌与2种西方类型癌症（结肠癌和肺癌）的比较呈正线性关系。5）移民到美国的日本人患膀胱癌的风险介于美国白人（高风险人群）和日本本土人（低风险人群）之间。同样这些日本移民患胃癌的风险也介于美国白人（低风险人群）和日本本土人（高风险人群）之间。总之，膀胱癌是一种具有性别和年龄差异的西方类型癌症。癌症风险也因人群的生活方式（取决于环境）而有所不同。从内分泌肿瘤学的角度对所得结果进行了讨论。
