Open AccessThe Global Challenge of Reducing Breast Cancer Mortality
Author(s) -
Burton Robert,
Bell Robin
Publication year - 2013
Publication title -
the oncologist
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.176
H-Index - 164
eISSN - 1549-490X
pISSN - 1083-7159
DOI - 10.1634/theoncologist.2013-0315
Subject(s) - overdiagnosis , breast cancer , medicine , cancer , demography , incidence (geometry) , mortality rate , physics , sociology , optics
Breast cancer, the second commonest cancer worldwide in 2008 (1.4 million new cases: 11% of all global cancers and 360,000 deaths), is the commonest potentially fatal cancer of women [1]. Breast cancer incidence has been increasing worldwide for decades, and there is currently a greater than 4-fold variation in age-standardized incidence rates between countries with the lowest (East and Southern Africa) and countries with the highest (Western Europe, North America and Australia/New Zealand). It is potentially one of the most curable of cancers; however, 5-year relative survival rates currently cover a 7-fold range based on analysis of data from cancer registries worldwide: 13% in Gambia, 31%-54% in India, 40% and 55% in the Philippines, 46% in Uganda, 57%-66% in Thailand, 57%-81% in South Korea, 58% in Zimbabwe, 58%-90% in China, 70% in Cuba and Costa Rica, 77% in Turkey, 60%-80% in Europe and 92% in the USA [2–4]. Note that 5-year survival rates are artificially high in some countries with established mammographic screening because of overdiagnosis [5]. Breast cancer mortality trends are not affected by overdiagnosis and are available for many high-income countries. After being on a plateau for decades, breast cancer mortality began falling in a number of those countries in about 1990, but in some countries such as Sweden as early as 1975 [6]. These declines in breast cancer mortality have mainly occurred where either or both of two effective interventions, shown to significantly reduce breast cancer mortality in randomized controlled trials (RCT), had been introduced into routine management of breast cancer: adjuvant therapy and mammographic screening. The first two of these sets of RCTs both began about half a century ago. One showed that a short course of adjuvant cyclophosphamide after clinical diagnosis and surgical removal of a breast cancer produced a statistically significant mortality reduction [7]. The other showed that screening for breast cancer with clinical breast examination (CBE) combined with mammographic screening could reduce breast cancer mortality (almost statistically significant) [8].