International comparison of colorectal and anus cancers incidence by detailed sites

This is the authors' abstract. We don't add key points for this paper.

In order to compare the percentage of colon, rectum, and anus cancer between Japan and other countries, we abstracted the number of cancer incidence and age-standardized incidence rates (ASRs) from the Cancer Incidence in Five Continents Vol. XI (CI5) (1). The International Agency for Research on Cancer provides the CI5 databases on the incidence of cancer recorded by cancer registries (regional and national) worldwide. We used the numbers of incidence case and ASRs from the following cancer registries, the United States of America (USA), Beijing in China, Mumbai in India, Hiroshima and Osaka in Japan, the Republic of Korea, Gironde in France, Hamburg in Germany, the United Kingdom (UK) and Australia from the CI5-XI database. Year of cancer diagnosis were from 2008 to 2012. Colon, rectum, and anus were coded as C18, C19-20, and C21 based on ICD-10, respectively. Figure 1 shows the distribution of cancer cases and ASRs by detailed sites among colon, rectum, and anus cancers in males and Figure 2 shows those in females. ASRs of colorectal cancer for males were higher than those for females in each studied countries (1.2 to 1.8 times higher for colon, 1.2 to 2.1 times higher for rectum). For males, ASRs of colorectal cancer in the Republic of Korea, Japan, and Australia (27 to 29 for colon, 18 to 23 for rectum) were higher, followed by France, Germany, and the UK (23 to 24 for colon, 13 to 16 for rectum). For females, ASRs of colorectal cancer in Australia, Japan, and Germany were slightly higher than those in the other countries. ASRs of colorectal cancer in India is the lowest for both males and females among studied countries. The distribution of colorectal cancer by detailed sites tends to be similar among countries. The proportion of colon cancer were more than 50% in all countries. The proportion of colon in the USA (65.7% for male, 71.0% for female) was the highest, while those in China, India, and the Republic of Korea were slightly lower (53 to 55% for male, 53 to 61% for females). By gender, the proportion of colon for females were 3 to 9 points higher than those for males in each countries. Particularly, in Japan, the proportion of colon for females were about 10 points higher than those for males (about 60% for male, about 70% for female). ASRs of anus cancer in Germany was the highest for both males (2.1) and females (2.8). The proportion of anus cancer were less than 5% among studied countries, except those for male in India (6.2%) and those for female in Germany (7.3%), France (6.1%), India (5.6%), and the USA (5.4%).