Breast cancer is the most common cancer affecting women globally. This paper discusses the current progress in breast cancer in Western countries and focuses on important differences of this disease in low- and middle-income countries (LMCs). It introduces several arguments for applying caution before globalizing some of the US-adopted practices in the screening and management of the disease. Finally, it suggests that studies of breast cancer in LMCs might offer important insights for a more effective management of the problem both in developing as well as developed countries. 1. Introduction Breast cancer is the most common cancer affecting women. Globally, about 1.4 million new cases are diagnosed each year [1]. Breast cancer incidence varies considerably throughout the world; age-standardized incidence is about 4-fold higher in high-income countries in North America and Western Europe compared to countries with the lowest per capita income [2]. A strong correlation between age-standardized incidence of breast cancer and the average gross domestic product per capita can be demonstrated [3]. However, in many low- and middle-income countries (LMCs), incidence is increasing at a faster pace than in developed countries, where the incidence is already high [4]. Several hypotheses for this rapid raise have been proposed. The most common explanation regards the rapid spreading of “westernization” of diet and lifestyle [4], characterized by switching to foods that have a high-energy density while decreasing physical activity, resulting in higher rates of obesity. Diet changes may also result in loss of protective factors associated with traditional diets. For example, westernization of diet in Japan and Japanese immigrants to the US is associated with marked increase of breast cancer incidence and mortality [5]. Changes in women’s reproductive patterns, often as a result of improved socioeconomic conditions, include the occurrence of earlier menarche and delayed or reduced parity, each recognized as additional risk factors of breast cancer [6]. Breast cancer in Singapore’s women exemplifies the impact of these changes as their incidence of breast cancer is rapidly approaching that seen in Europe [7], a worrisome sign of the looming epidemic of breast cancer in other rapidly developing countries such as China and India. In addition, longer lifespan, better policies for reporting disease diagnosis and the introduction of screening, at least in some countries, all contributed to the increasing breast cancer incidence in LMCs. 2. Differences in Epidemiology and
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