ABSTRACT
Facebook is one of the main communication tools in the world nowadays. In Brazil, it is used for almost half of the population. Knowing what is conveyed about cancer by this social network can be an important step for the development of efficient health communication strategies. We evaluate Facebook user's comments on pages about cancer; verify if there is a pattern of public awareness on the disease and compare it with results from other studies. Three pages about cancer on Facebook were selected among those with more followers in Brazil. For 6 months, from January to June 2014, all posts were selected and evaluated, and we created eight categories. On each page, the categories that generated most comments were elected for the second analysis. The behavior of empowered citizens by new communication tools is the target of this study. Similarities and differences between 12,926 comments coming from 1243 posts in three different Facebook pages on cancer were analyzed. Four new categories were identified: "religion," "positive," "negative," and "information." Despite the differences among the three pages selected for this study, we observed the predominance of positive speeches associated with religious terms. Following public perceptions on cancer is an important step for the development of efficient health communication strategies.