Breast cancer in Arab populations: molecular characteristics and disease management implications.

Breast cancer is a major health problem in both developing and developed countries. It is the most frequently diagnosed female malignant disease in Arab populations. The incidence of breast cancer is lower in Arab countries than in Europe and the USA but is rising fast. Breast cancers in women from Arab populations have different characteristics to those reported in individuals from Europe and the USA. For example, affected patients are at least a decade younger, they have a more advanced stage of disease at first presentation, and their tumour size is larger. Moreover, in some Arab populations, reports suggest increased axillary-lymph-node invasion, a larger proportion of negative hormone receptors, and a higher tumour grade. These disparities are not only confined to clinicopathological features but also exist at the molecular level, as shown by findings of genome-wide association studies and expression profiling.