WEDNESDAY, April 5 (HealthDay News) — There has been slow but steady progress in fighting certain cancer risk factors, most notably smoking, but roadblocks remain when it comes to other factors such as obesity.

Those student loan calculator are the key findings from the newly published Cancer Prevention & Early Detection Facts and Figures 2006, a report released annually by the American Cancer Society since 1992.

The report’s authors stress that at least half of cancer deaths are preventable, meaning that hundreds of thousands of American lives could still be saved each year by early detection and prevention measures.

“The factors that contribute to cancer and the factors that help to prevent cancer and detect it early don’t change overnight,” said Elizabeth Ward, co-author of the report and director of surveillance research in the department of epidemiology and surveillance research at the American Cancer Society in Atlanta. “This reflects that we have a great deal of knowledge about certain major causes of cancer and major preventative actions that people can take and these still need to take hold.”

“This is incredibly powerful information,” added Dr. Jay Brooks, chairman of oncology/hematology at the Ochsner Clinic Foundation in Baton Rouge. “Making progress on cancer is not going to be made by a pill that cures it. Cancer is caused by a number of things . . . The things that we have been doing and preaching are making real progress.”

Just this past February, the ACS reported that the number of cancer deaths in the United States dropped slightly in 2003, the first such decline since 1930. The society’s Cancer Facts and Figures report found that from 2002 to 2003 U.S. cancer mortality fell by 369 deaths — from 557,271 in 2002 to 556,902 the following year.

And companies according to this new report released Wednesday, more than 170,000 cancer deaths will be attributable to tobacco use in 2006. About one-third of the 564,830 cancer deaths expected to occur in 2006 will be related to poor nutrition, physical inactivity, overweight and obesity.

At least half of all cancer deaths, especially from cancers of the breast, colon, rectum and cervix, could be prevented by proper screening and other methods.

Perhaps one of the most heartening findings was that tobacco use in the United States is at its lowest point since the start of World War II. This despite $15.15 billion spent by the tobacco industry on promoting cigarettes domestically (nearly 23 times the funding allotted to tobacco control in 2003).

“It’s really the result of cumulative public health efforts to educate the public about the dangers of tobacco and also due to the imposition of excise taxes and state tobacco-control programs,” Ward said.

The percentage of high school students who smoke has decreased, to 22 percent in 2003 from 36 percent in 1992. And between 1997 and 2004, the percentage of adults who smoke declined from 27.6 percent to 23.4 percent in men and 22.1 percent to 18.5 percent in women.

Nonetheless, Ward continued, “smoking still remains unacceptably high among both adults and young people.”

The burgeoning epidemic of overweight and obesity is also contributing to deaths from a number of different cancers. The proportion of children aged 6 to 19 who are overweight has tripled over the past 30 years while the percentage of adults who are obese more than doubled from 15 percent in 1976 to 31.1 percent in 1999-2002. This trend shows no sign of slowing down, the report stated.

Related to this troubling trend are declining rates of physical activity, low consumption of fruits and vegetables and high consumption of “competitive foods” such as those sold in vending machines or cafeterias.

“Obesity in this country is the second leading cause of cancer, and we are raising a generation o