Breast Cancer in Hong Kong
Breast cancer is the most common cancer in women and a major cause of death in Hong Kong. Not only is this true in Hong Kong but also many parts of Asia. The rate of increase is noticeably high in the premenopausal age group and in particular, in Hong Kong, there is a peak rate in the 40s which is not seen in Caucasian population. In addition, the increasing incidence in post-menopausal breast cancer seen in the Caucasian population is not present. Although this may be partially due to the change in environment and adaptation of Western lifestyle, it does not fully explain this rapid increase in numbers in young women in both Hong Kong and the Asian countries. It has been suggested that genetic predisposition to the disease and its interaction with the environment may be more important in Asian women including Chinese than in the Caucasian women.

About 15% of women with breast cancer have a family history of breast cancer (familial cause) and 5-10% is known to have a hereditary cause where a mutated gene can be passed on from generations to generations. A percentage of these women, especially those who are young or have a family history, will have a hereditary cause. Mutations of the BRCA 1 and BRCA 2 genes account for over 80% of the familial breast cancers and increase a life time risk of breast cancer greatly to 85%, which is 10 times more than the population risk. In addition, it also increases the lifetime risk of ovarian cancer to 50 times the population risk, and therefore this has much significance in the management of this high-risk group of women. Breast cancer does not only exclusively affect women as men can also suffer from breast cancer and inherit this hereditary syndrome where breast cancer risk will increase by 60 fold compared to the normal male population.