Global trends in breast cancer show disparities by countries

Photo courtesy of University of Calgary News

CANCER DIGEST – July 31, 2020 – Breast cancer rates are increasing among pre- and postmenopausal women around the world, but trends are different in low-income countries versus high-income countries, say a group of Canadian researchers.
The increase in breast cancer rates in premenopausal women in high-income countries was a bit of a surprise to the researchers led by Miranda Fidler Benoudia, PhD of the Cumming School of Medicine at the University of Calgary, Canada. The study was published in the July 22, 2020 journal Lancet Global Health.

“When young people get cancer, the impact on them is huge and it can lead to major repercussions later in life,” says Dr. Fidler-Benaoudia in a press release. "For example, the current life expectancy in Canada is around 80 years, so when a person is diagnosed at 30, they could live another 50 years where they are more likely to experience major health, financial and career repercussions compared to the general population as a result of their treatment.”

The study involved a population-based analysis of global breast cancer incidence and mortality using GLOBOCAN, a database maintained by the International Agency for Research on Cancer that tracks cancer in 44 populations in 41 countries on five continents.

When they analyzed the 645,000 breast cancers that occurred in premenopausal women and the 1.4 million post menopausal women, they found that in higher-income nations, including Canada, rates of breast cancer in premenopausal women are increasing, while postmenopausal breast cancer is increasing more rapidly in lower-income countries.

The study highlights the inequities in cancer mortality worldwide, showing that about 47 per cent of women diagnosed with premenopausal breast cancer in less developed countries will die, compared to only 11 per cent per cent in the most developed countries. Postmenopausal breast cancer saw a fatality rate of 56 per cent in less developed nations compared to 21 per cent in their more developed counterparts.

“The findings from this study show important differences in the breast cancer burden by age and point to the need for prevention initiatives such as efforts to reduce obesity and alcohol consumption, increase physical activity and breastfeeding — all of which reduce one’s risk for developing breast cancer,” says Fidler-Benaoudia.

Sources: UCalgary News press release and The Lancet Global Health