The number of people with cancer is likely to surge by more than ­­75 percent across the world by 2030, with particularly sharp rises in poor countries as they adopt unhealthy “Westernized” lifestyles, a study said last week.

Many developing countries were expected to see a rise in living standards in coming decades, said the paper from the World Health Organization’s International Agency for Research on Cancer.

But those advances could come at a cost: an increase in breast, prostate and colorectal cancer linked to poor diet, lack of exercise and other bad habits associated with affluence, it added.

“Cancer is already the leading cause of death in many high-
income countries and is set to become a major cause of morbidity and mortality in the next decades in every region of the world,” said Freddie Bray of the WHO agency.

The study was the first to look at how current and future rates of cancer might vary between richer and poorer countries, as measured by development rankings defined in the United Nations’ Human Development Index.

Researchers found poorly developed countries — mostly those in sub-Saharan Africa — had high numbers of cancers linked to infections, particularly cervical cancer, but also liver cancer, stomach cancer and Kaposi’s sarcoma. By contrast, richer countries had more cancers associated with smoking and with obesity and poor diet.

The researchers said that rising living standards in less developed countries would probably lead to a decrease in the number of infection-related cancers. But it was also likely there would be an increase in types of the disease usually seen in richer countries.

They predicted that middle-
income countries such as China and India might see an increase of 78 percent in the number of cancer cases by 2030.

Cases in less developed regions were expected to see a 93 percent rise over the same period, said the paper, published in the journal Lancet Oncology.

Those rises would more than offset signs of a decline in cervical, stomach and other kinds of cancer in wealthier nations, said the researchers.

Christopher Wild, director of the study, said it showed “the dynamic nature of cancer patterns” across the world over time.

“Countries must take account of the specific challenges they will face and prioritize targeted interventions,” he said, emphasizing the need for prevention measures, early-detection systems and effective treatment programs.

The study used data from a WHO database of estimates of cancer incidence and death rates in 2008 in 184 countries worldwide.

The researchers determined how patterns of the most common types of cancer varied according to four levels of human development, and then used these findings to project how the cancer burden is likely to change by 2030.

The seven most common types of cancer worldwide are lung cancer, female breast cancer, colorectal cancer, stomach cancer, prostate cancer, liver cancer and cervical cancer.

— Reuters