Breast cancer deaths fall in S’pore despite more cases, thanks to earlier diagnoses and better treatment

SINGAPORE – Earlier diagnoses and improved treatment are the reasons there are fewer deaths in Singapore from breast cancer, despite a sharp rise in incidence of the disease over the past three decades, according to new research.

However, global breast cancer cases and deaths from the disease are projected to rise in the coming decades, according to an analysis from the Global Burden of Disease (GBD) study.

Published in The Lancet Oncology on March 2, the study showed that the number of breast cancer cases in the Republic rose from 41.58 per 100,000 women in 1990 to 62.33 per 100,000 women in 2023 – an increase of almost 50 per cent.

Over the same period, the cancer’s mortality rate fell 23.4 per cent, to 12.47 deaths per 100,000 women – lower than the global average of 16.14 per 100,000.

This is a result of improved treatment as well as earlier diagnoses, said one of the study’s senior authors, Associate Professor Marie Ng from the NUS Yong Loo Lin School of Medicine (NUS Medicine).

More than 57 per cent of local breast cancer cases are now detected at Stage 1, she said, citing data from the Singapore Cancer Registry.

“Once you’re diagnosed at Stage 1, your prognosis is much better,” said Prof Ng, who is also director of the NUS-IHME GBD Research Centre, a collaboration between NUS Medicine and the Institute for Health Metrics and Evaluation (IHME) at the University of Washington.

She pointed to greater longevity as one reason for the rise in cases, as cancer risks increase with age.

The increase in risk factors such as diabetes and obesity could also have played a role in the spike in cases of the disease, she suggested.

Similar to the situation in other higher-income countries, later pregnancies and fewer births here could also be linked to increased breast cancer risk, she noted.

Breast cancer is the most common cancer among women in Singapore, accounting for around 30 per cent of all cancer diagnoses in women here.

Worldwide, breast cancer rates have risen about 149 per cent since 1990, with some 2.3 million cases recorded in 2023, while deaths increased by about 110 per cent to 764,000 during that time.

This increase is projected to continue. In 2050, more than 3.5 million new cases and 1.4 million deaths are expected.

A greater burden is likely to be borne by low- and lower-middle-income countries, noted the study’s lead author Kayleigh Bhangdia of IHME.

She attributed this to later-stage diagnosis, more limited access to quality care and higher death rates in such countries.

Risk factors

In 2023, 28 per cent of the global breast cancer burden – equivalent to 6.8 million years of healthy life lost to disease and early death – was linked to six modifiable risk factors, the study found.

The biggest impact was seen in high red meat consumption – linked to almost 11 per cent of all healthy life lost.

The other factors were tobacco use, high body mass index, high blood sugar, high alcohol use and low physical activity.

While the burden associated with high alcohol use and tobacco use had fallen by 47 per cent and 28 per cent, respectively, since 1990, other factors had not shown the same progress, the researchers said.

This is in line with findings from research by the World Health Organization, which suggested that almost four in 10 cancer cases worldwide in 2022 were linked to preventable causes such as smoking, drinking and air pollution.

Curbing the growing burden of breast cancer both in Singapore and worldwide requires addressing risk factors via effective public health policies and making healthier choices more accessible, said Dr Alicia Ong, adjunct lecturer in the family medicine division at NUS Medicine and a family physician with National University Polyclinics.

“Prevention, early detection and access to care must go hand in hand,” said Dr Ong, who is one of the GBD study’s co-authors.

Prof Ng is hopeful Singapore can buck the trend of higher mortality from breast cancer, should more people get diagnosed at the earlier stages of the disease.

On March 5, Health Minister Ong Ye Kung announced that subsidised genetic testing would be extended to hereditary breast and ovarian cancer, associated with a mutation in genes such as BRCA1 or 2.

This, together with the substantial subsidies afforded to breast cancer screening here, means screening is quite accessible, said Prof Ng.

“I really want to emphasise that we should take advantage of the service and resources available,” she said. “Breast cancer has become a very treatable condition, and so (the chance of) survival is very, very high if we catch it early.”