European country comparisons provide evidence of a link between colon cancer and adenocarcinoma development in the lung but not the oesophagus.

Relative incidence rates of lung cancers demonstrate marked international variation in values for the different histological sub-types. In order to determine whether adenocarcinomas (ACs) in this site might share risk factors with other ACs, for example, in the breast, prostate, oesophagus and colon, a comparison of data in the IARC/WHO Cancer Incidence in Five Continents (Volume VII) was made for selected registries in Europe. Significant correlations were found between lung AC incidences/100,000 population and prostate and colon cancers in males (P < 0.005 and P < 0.05, respectively) and for breast and colon in females (P < 0.05 for both). Partial correlation coefficients were significant for lung and colon (P < 0.001) and prostate and colon (P < 0.005) in men, and for breast and colon in women (P < 0.005). A significant negative correlation with prostate cancer was noted for lung ACs in men. The results provide support for shared risk factors between lung Acs and colon cancers but do not indicate any link with AC development in the oesophagus. Data from registries in the UK and Italy were remarkable for high incidences of oesophageal and lung ACs, respectively, pointing to major differences in environmental risk factor or beneficial influence acting on these sites between the two countries.