Breast cancer in South America: challenges to improve early detection and medical management of a public health problem.

Breast cancer is a public health issue in South America, with about 70,000 cases and 30,000 deaths expected for the year 2001 according to the World Health Organization database. This is especially the case for the so-called temperate region that includes Argentina, Chile, Uruguay, and Southern Brazil. In these areas, the incidence of breast cancer is in the same range as in most countries in Europe. Notably, Argentina has one of the highest incidences of breast cancer in the world, while in Brazil breast cancer is the second most frequent type of cancer (after skin cancer). The potential risk factors for the higher incidence of this disease in temperate South America are, among others, a high-fat diet, more elevated socioeconomic status, and the low average parity of women. In addition, the influence of European immigration on the genetic background of the population should be considered. Late diagnosis is a major factor affecting the mortality rates, as a significant proportion of patients are still diagnosed at clinical stages II and III. In this article, the available data on the incidence and mortality rates of breast cancer in South America, as well as the published literature on risk factors and the limitations of early detection of the disease, are discussed. The overall management of patients diagnosed at clinical stage IIIA is briefly addressed.