Thursday January 3 1:15 PM ET

Rate of Cancer Highest in North America: Study

NEW YORK (Reuters Health) - North America leads the world in the rate of cancers diagnosed in adults, followed closely by Western Europe and Australia and New Zealand, according to a recent estimate of worldwide cancer rates.

The study found that 1.5% of the North American population aged 15 years and older--more than 3 million people--had been diagnosed with at least one of 25 different cancers within the past 5 years. The results only include individuals diagnosed in the past 5 years because people who live longer are considered to be cured, researchers explain in the January issue of the International Journal of Cancer.

About 1.2% of the population of Western Europe, or nearly 4 million people, had been diagnosed with cancer between 1986 and 1990, while just over 1% of the population of Australia and New Zealand--about 200,000 people--had been diagnosed over the same period.

Japan was next in line with 1% of the population diagnosed with cancer within the past 5 years, followed by Eastern Europe with 0.7% of adults living with cancer, and Latin America and the Caribbean countries with 0.4% of the population diagnosed with cancer, according to the report.

The researchers suggest that higher cancer rates in nations with higher income reflect longer life expectancies in older adults, who are more susceptible to cancer.

``Most of the difference is explained by different demographic patterns with high-income countries having long life expectancy in age groups when the risk of the disease is highest,'' write Dr. Paola Pisani and colleagues from the International Agency for Research on Cancer in Lyon, France.

In other findings, cancer rates were similar for men and women living in developed countries. In developing nations, however, more women lived with cancer for at least 5 years, suggesting that men are more frequently stricken with cancers that do not respond well to treatment, such as liver, esophagus and stomach cancers.

Breast cancer was the most common type of cancer diagnosed in women regardless of country. In men and women living in developed nations, colorectal cancer was the second leading cause of cancer, followed by cancer of the lung, bladder and stomach in men.

The study did not include the most common types of skin cancer, which are extremely prevalent and rarely life threatening, but did include melanoma, a relatively rare and dangerous type of skin cancer.

The results of the study can inform decisions regarding the delivery of healthcare services, the researchers explain.

SOURCE: International Journal of Cancer 2002;97:72-81.