New cases of cancer will rise by half by 2030, reaching 21.6m per year compared to 14m in 2012, according to a global analysis of the disease by the United Nations.

The report was compiled by the International Agency for Research on Cancer (IARC).

It said cancer deaths will likely rise from 8.2m to 13m per year as the world's population grows, ages and more people adopt risky lifestyle habits.

It took aim at Big Tobacco, saying its sales drive was "inextricably linked" to a likely surge in lung cancer.

The report released yesterday, on the eve of World Cancer Day, was compiled by more than 250 scientists from over 40 countries.

It is the first such overview in six years.

World Health Organisation Director General Margaret Chan, whose agency oversees the IARC, said the overall impact from cancer would "unquestionably" hit developing countries the hardest.

These nations are already grappling with poverty-associated cancers caused by infection or disease, she said.

Added to that will be cancers blamed on more affluent lifestyles such as high tobacco and alcohol use, eating processed foods and not exercising enough.

IARC Director Christopher Wild said the focus should be on prevention.

He said: "The particularly heavy burden projected to fall on low and middle-income countries makes it implausible to treat our way out of cancer."

Mr Wild added "that even the highest-income countries will struggle to cope with the spiralling costs of treatment and care".

Cancer overtook heart disease as the number one cause of death in the world in 2011.

New cases will likely rise to 19.3m in 2025, with 11.4m deaths, said Mr Wild. By 2035, new cases would number about 24m per year.

The report found a slight gender bias with 53% of cancer cases and 57% of deaths among men.

In men, cancer most often attacked the lungs (16.7%) followed by the prostate (15%), colorectum (10%), stomach (8.5%) and liver (7.5%).

For women, cancer was most common in the breast (25.2%), colorectum (9.2%), lung (8.7%), cervix (7.9%) and stomach (4.8%).

Differences in industrialised countries versus low-income countries

There were also regional imbalances: more than 60% of the world's cancer cases and 70% of deaths occurred in Africa, Asia and Central and South America, the report said.

Measured as a proportion of the population, however, high-income countries in North America and western Europe as well as Japan, South Korea, Australia and New Zealand, had higher figures.

Cancers of the breast, colorectum and prostate were more typical of the industrialised world and those of the liver, stomach and oesophagus more common in low-income countries.

China bears the brunt of new cases.

Almost half the new cases diagnosed in 2012 were in Asia, most of them in China, said the report.

Europe had nearly a quarter of cases, the Americas about a fifth, and Africa and the Middle East just over 8%.

But when it came to deaths, Asia's share jumped to more than 50% and that of Africa and the Middle East to nearly 10%, while the Americas' share shrank to under 16% and that of Europe to 21.4%.

Cancer is typically diagnosed at a more advanced stage in less developed countries, and treatment is less readily available, said the report.

Globally, lung cancer was the biggest killer with 19.4% of the total, followed by cancer of the liver with 9.1% and stomach with 8.8%.

The report said lung cancer was "inextricably linked to the global tactics of tobacco companies aiming to expand their sales".

A smoking "epidemic" was evolving in poor countries, it said, "potentially impeding human development by consuming scarce resources, increasing pressures on already weak health-care systems, and inhibiting national productivity".

The report said the total, annual economic cost of cancer to the world was estimated at about $1.16 trillion in 2010, "yet about half of all cancers could be avoided" through prevention, early detection and treatment.

Prevention includes vaccination against hepatitis B and the human papillomavirus, which can reduce cancers of the liver and cervix, the promotion of physical activity to counter obesity, thought to be a factor in bowel and breast cancer, and tougher anti-tobacco campaigns.

'Affluent lifestyle changes' to blame for cancer increase

A consultant oncologist at St Vincent's Hospital in Dublin has said "affluent lifestyle changes" are to blame for an increase in cancer cases in Ireland. 

Dr Janis Walsh said increasing obesity, reduced exercise and increased alcohol intake are the main factors responsible and those with a body mass index (bmi) in excess of 25 tend to have an increased risk of cancer.

Dr Walsh said that changing lifestyle choices would radically cut the risk of cancer.

"It is estimated that we could reduce our cancers by between 30 and 50% by making sure we are of adequate weight, that we are exercising, and right now what's recommended is 30 minutes up to five times a week."

She added that studies have shown that reducing alcohol intake would also reduce the risk. 

"So what we see in terms of cancer, particularly my area of interest would be breast cancer, we have many studies saying that if we go beyond two units a day there's an increased cancer risk associated with that and an increased cancer recurrence rate."

Dr Walsh said that an increase of cancers in the developing world is due to a lack of screening such as for breast and cervical cancer. 

She said that new campaigns aimed at tackling obesity were very positive and that education would be the key to preventing cancer cases among younger generations.

"Education is the important thing here and I think that getting into our schools on an early basis will be key in terms of educating about careful sun exposure, appropriate foods to eat, the importance of getting out and exercising."