Study shows gender isn't lung-cancer risk

Women over age 60 who never smoked outnumber male counterparts.
SCRIPPS HOWARD
Women who've never smoked are not more likely to die from lung cancer than are their male counterparts, according to a new study from the American Cancer Society that counters recent conventional wisdom about the disease.
While it is true that about 20 percent of female lung-cancer patients never smoked, compared with about 1 in 10 male lung-cancer patients, "the reason appears to be unrelated to cancer risk," said Dr. Michael Thun, chief epidemiologist for the Cancer Society and lead author of the new study, published today in the Journal of the National Cancer Institute.
"Instead, it appears to be the result of the fact that there are far more women than men over the age of 60 who never smoked. Census data show there are about 16.2 million women compared to just 6.4 million men in the U.S. who are over 60 and never smoked."
The average age of an American getting a lung-cancer diagnosis is 70.
Smoking at some point in a lifetime accounts for 85 percent to 90 percent of lung-cancer cases, but the Cancer Society estimates that 15,000 Americans who never smoked die from lung cancer each year. However, Thun says the number of nonsmokers diagnosed with the disease doesn't seem to be rising significantly.
Weight-conscious women
Overall, lung-cancer deaths have increased by 20 percent for men since 1988, compared with a 150 percent increase among women. But experts say this is mainly due to the fact that smoking rates have declined among women at a much slower pace than among men since the 1960s. Many women believe that smoking helps them control their weight, and once they start smoking, women often find it harder to quit than men do.
The new study looked at smoking status and age, sex and race-specific lung-cancer death rates among more than 940,000 Americans enrolled in one of two national cancer-prevention studies, one from 1960 through 1972, the second that began in 1982 and is ongoing, with the latest mortality data entered from 2002.
The study group included 1,498 people who never smoked but died from lung cancer. Thun and colleagues found that the annual rate of dying from lung cancer per 100,000 people was 18.7 for men compared with 12.3 in women during the earlier study period.