A GROUNDBREAKING genetic study among Asian women has revealed that a tool developed to help European women assess their breast cancer risk also works on Asian women.
The tool, called Polygenic Risk Score (PRS), separates people into different risk groups based on their genetic sequence to predict their future risk of developing breast cancer.
The results can empower women to decide which screening and prevention is right for them, and help reduce inefficiency, unnecessary cost and even possible harm caused by over-diagnosis.
This is the first large study of the PRS in an Asian population, says Cancer Research Malaysia chief scientific officer and co-lead of the project, Professor Datin Paduka Dr Teo Soo Hwang.
Previously, Asian studies were nearly six times smaller than those among European women. Due to lack of data in Asians, it was unclear if the PRS was effective in predicting breast cancer risk in non-European women.
"Through the significant increase in data from Malaysia and Singapore, we now know PRS can help us identify more accurately who are at high risk of breast cancer.
"Our results suggest that only 30 per cent of Malaysian and Singaporean women have a predicted risk similar to that of European women, and that using the PRS accurately identifies these high-risk women," says Teo.
ASIAN EVALUATION
The study evaluated the PRS in 45,212 Asian women from Singapore, Malaysia, Japan, Korea, China, Hong Kong, Thailand, Taiwan, USA and Canada.
"Our study is a critical piece of the puzzle that helps us better understand breast cancer risks in different women around the world," says Centre for Cancer Genetic Epidemiology director and co-lead of the study, Professor Douglas Easton of the University of Cambridge.
"There are differences in the genetic make-up of Asian women compared to women of European descent, which means their propensity to develop breast cancer may be different," he says.
Understanding this can help work out why some women are at higher risk of the disease, which in turn would help improve screening, prevention and ultimately treatment of the disease, explains Easton.
Women are generally advised to start breast screening at age 50.
However, in most Asian countries, many women who could be at risk of breast cancer do not go for screening. This leads to late detection and a lower survival rate.
Risk-based screening may be particularly important in low- and middle-resource countries that do not have population-based screening, such as Malaysia.
Malaysia anticipates a 49 per cent increase in breast cancer cases from 2012 to 2025. The country also has a much lower five-year survival rate for breast cancer compared to other Asian countries.
The survival rate is 63 per cent in Malaysia compared to 92 per cent in South Korea and 80 per cent in Singapore.