he study showed a reduction of 19% in mortality from breast cancer overall between 1989 and 2006. For individual countries, the trend ranged from a 45% fall in Iceland to a 17% increase in Romania. In 15 countries, the fall was over 20%, but these tended to be countries where the initial rate was higher.

About 9,700 women in Belgium are diagnosed with breast cancer every year, or 109 per 100,000, compared to 93.5 10 years ago. Some 2,500 die of the disease every year. The rate of diagnosis is higher than any other country but, as experts reacting to the figures explained, that is not necessarily a sign Belgium is doing something wrong – it may in fact be a sign of doing something right.

“Breast cancer is a typical disease of prosperity,” said Erik Van Limbergen, head of oncology at Leuven University Hospital. Cancer as a whole is generally a disease of middle age to later life, which means that as life spans increase, so do cancer rates.

Modern western lifestyles are also a factor: being overweight is considered an important risk factor for breast cancer. Other hypotheses concern oestrogen and oestrogen-like compounds in the water supply, consumed by humans and by the animals that humans eat. Western women also tend to have fewer children, and have them later in life – both factors which increase the risk of breast cancer.

Another factor influencing the rates of breast cancer is the prevalence of screening: an in- crease in screenings reveals more cases of breast cancer. The Flemish Health and Care Agency provides free screening every two years to all women aged between 50 and 69. While increased screening has an immediate effect on the numbers of patients diagnosed, it produces only a delayed effect on mortality figures. A woman diagnosed with a serious tumour including metastases could, with treatment, live for five years. A woman who undergoes screen- ing and has a small tumour whose growth is arrested – half of all tumours caught by screening are under one centimetre and never develop symptoms – only becomes a cut in mortality rates later. It takes several years, in other words, before the effects of screening show up in the figures.

Screening is viewed by many oncologists as the most serious carcinogenic activity. When the Netherlands introduced a tough screening programme, incidences of breast cancer rose by 50-60%. The reason is that most cancers detected would never have been fatal, even if left alone. A woman with a small tumour becomes a cancer statistic, while another with exactly the same tumour, but who is never screened, is not.

At the same time, groups considered to be high-risk for breast cancer, such as lower income groups and immigrant women, tend to be less likely to show up for screening.

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