Correlation patterns of cancer relative frequencies with some socioeconomic and demographic indicators in Brazil: An ecologic study

Sex-specific relative frequencies (RF) of oral, esophageal, stomach, colon, rectal, laryngeal, lung, female breast, cervical and penile cancers obtained from a government-sponsored, nation-wide data base of histopathological diagnoses were evaluated with respect to all possible inter-site correlations and with 12 socioeconomic and demographic variables for 23 States in Brazil. Use of bivariate and multivariate methods detected a high positive intercorrelation among RFs of lung, laryngeal and colon cancers regardless of sex. RFs for these 3 sites were also positively correlated with many markers of State development and affluence. Cervical and penile cancers emerged as a distinct subset with respect to their correlation patterns. RFs for these neoplasms were highly (positively) correlated (r = 0.8606, p less than 0.001) with each other and exhibited intense negative associations with many of the affluence markers and the former cancer sites. Bivariate correlations generally exhibited a better fit with female-specific RFs than with data from males which was reflected in the number of strong correlations detected by sex.