Spectrum of breast cancer in Asian women

Abstract

Introduction: Breast cancer is the leading cause of cancer-related deaths in Asia, and in recent years is emerging as the commonest female malignancy in the developing Asian countries, overtaking cancer of the uterine cervix. There have been no studies objectively comparing data and facts relating to breast cancer in the developed, newly developed, and developing Asian countries thus far.

Material and methods: This multi-national collaborative study retrospectively compared the demographic, clinical, pathological and outcomes data in breast cancer patients managed at participating breast cancer centers in India, Malaysia and Hong Kong. Data, including those on the availability of breast screening, treatment facilities and outcomes from other major cancer centers and cancer registries of these countries and from other Asian countries were also reviewed.

Results: Despite an increasing trend, the incidence of breast cancer is lower, yet the cause-specific mortality is significantly higher in developing Asian countries compared with developed countries in Asia and the rest of the world. Patients are about one decade younger in developing countries than their counterparts in developed nations. The proportions of young patients (< 35 years) vary from about 10% in developed to up to 25% in developing Asian countries, which carry a poorer prognosis. In the developing countries, the majority of breast cancer patients continue to be diagnosed at a relatively late stage, and locally advanced cancers constitute over 50% of all patients managed. The stage-wise distribution of the disease is comparatively favorable in developed Asian countries. Pathology of breast cancers in young Asian women and the clinical picture are different from those of average patients managed elsewhere in the world. Owing to lack of awareness, lack of funding, lack of infrastructure, and low priority in public health schemes, breast cancer screening and early detection have not caught up in these under-privileged societies.

Conclusions: The inadequacies of health care infrastructures and standards, sociocultural barriers, economic realities, illiteracy, and the differences in the clinical and pathological attributes of this disease in Asian women compared with the rest of the world together result in a different spectrum of the disease. Better socioeconomic conditions, health awareness, and availability of breast cancer screening in developed Asian countries seem to be the major causes of a favorable clinical picture and outcomes in these countries.