The cancer rate among Shanghai's women almost doubled in the past 20 years and is the highest in the nation, health officials said on Wednesday.

There is now one cancer patient for every 100 woman in the city, officials from the Shanghai Disease Prevention and Control Center said Wednesday as they prepared to mark International Women's Day.

Among the reasons for the city's alarming status, the 82.5-year average lifespan of local women is five years longer than elsewhere in China, giving them a greater chance to develop cancer; dietary habits are changing; and lifestyles are becoming more unhealthy, experts said.

"Old age means fading immunity," said Dr Di Wen, a member of the Chinese Medical Association's gynecological tumor branch. "A fatty diet and the failure to breast-feed children can be causes for breast cancer, while an increased number of sex partners means a higher risk for cervical cancer."

Breast cancer was the most common malignancy, affecting 30 percent of female patients, who made up more than 56 percent of Shanghai's 13,400 cancer patients in 2004, though they comprised less than half of the population.

"Early detection and treatment are crucial for cancer prevention and recovery," said Lu Wei, vice director of the Shanghai center.

A recent survey of 13,000 women by the city's disease control center found that only 47 percent had received a health check within the previous five years. Twenty-seven percent failed to follow a healthy diet, 23 percent were overweight, 14 percent were classified as obese, 57 percent suffered second-hand smoking, 29 percent seldom exercised, and 74 percent weren't aware of the need for breast checkups.

The center is planning a series of educational programs this year to promote early detection and treatment.

(Shanghai Daily March 9, 2007)