Cross-country comparisons suggest shared risk factors for carcinomas, including male lung adenocarcinoma and colon cancer development

Sex disparities in the association of lung adenocarcinoma with colorectal cancer

Background: Most cancers share common risk factors. It might provide evidence of shared risk factors with cancers by investigating cross-country and cross-township comparisons.

Methods: The data were obtained from International Association of Cancer Registries/World Health Organization and the National Cancer Registration Program of Taiwan. Age standardized incidence rates were calculated among gastric cancer, colorectal cancer and lung adenocarcinoma in 19 countries from 1995 to 1998. The Pearson correlations were also compared among 3 types of cancers for both sexes.

Results: The incidence rates of gastric and colorectal cancer throughout different countries show male dominance with a male-to-female sex ratio of around 2 and 1.5, respectively. Significant cross-country correlations in colorectal cancer (r=0.918, p<0.001), gastric cancer (r=0.985, p<0.001) and lung adenocarcinoma (r=0.685, p=0.001) were observed between men and women. There was a significant international correlation between colorectal cancer and lung adenocarcinoma in men (r=0.526, p=0.021), but not in women. In cross-township comparisons of Taiwan, there were significant correlations in colorectal cancer (r=0.451, p<0.001), gastric cancer (r=0.486, p<0.001), and lung adenocarcinoma (r=0.217, p<0.001) between men and women. There were links of lung adenocarcinoma and gastric cancer (r=0.122, p=0.024) and colorectal cancer (r=0.128, p=0.018) in women, and lung adenocarcinoma and colorectal cancer in men (r=0.276, p<0.001).

Conclusions: There were associations between lung adenocarcinoma and colorectal cancer between and in both sexes in Taiwan, but not in cross-country comparisons. The results suggest that some factor, like genes, may be important as determinants for the association between lung adenocarcinoma and colorectal cancer.

Understanding global nutrition dynamics as a step towards controlling cancer incidence

As we look to understand future forces that will affect cancer risk, poor dietary patterns, overweight and obesity are significant concerns. In the past two decades these factors have shifted from issues that face higher-income countries to a global pandemic, and are rapidly becoming less a problem of affluence and more a problem of poverty. Rapid shifts in food systems, food pricing and marketing are the causes that underlie this trend. It is imperative to understand these factors and implement global interventions to slow this pandemic. The alternative is an acceleration of the incidence of the main nutrition-related cancers, primarily in developing countries.

A Geographic Correlation Study of the Incidence of Pancreatic and other Cancers in Whites

Ecologic analyses of cancer incidence rates may be helpful to formulate hypotheses on risk factors and mechanisms of poorly known neoplasms, such as pancreatic cancer. We calculated sex-specific pair-wise and partial (after adjustment for lung cancer incidence) correlations between the incidence of pancreatic cancer and that of 23 other cancers in two international sets of cancer incidence data: the recorded or estimated incidence for 2000 in 38 European countries and the recorded incidence in Whites for 1993-1997 in 35 cancer registries from North America and Oceania. In both sexes and datasets, a strong, highly significant correlation was present between the incidence of pancreatic cancer and that of lung and kidney cancer. For the latter, correlation coefficients in the European data were 0.71 in men and 0.74 in women (both p<0.0001); in the cancer registry data they were 0.57 (p=0.0004) in men and 0.45 (p=0.007) in women. The results on kidney cancer were not modified by adjustment for the correlation with lung cancer, were confirmed by the application of spatial regression models and, with the exception of men in the cancer registry data, were confirmed in sensitivity analyses restricted to the populations with data of best quality. Weaker, less consistent correlations were found for colorectal, endometrial, ovarian and bladder cancers. Tobacco smoking is a plausible explanation of the association between pancreatic and lung cancer; the association with kidney cancer likely reflects additional common etiologic and pathogenetic factors of the two neoplasms.