Cancer death rates are dropping among African Americans in the United States, but the gap between blacks and whites remains large, according to the latest estimates from the American Cancer Society.

The report, Cancer Facts & Figures for African Americans 2005-2006, projects 137,910 new cases of cancer among African Americans in 2005, and 63,110 cancer deaths. As in the US population overall, lung, breast, prostate, and colorectal cancers take the highest toll.

The death rate for all cancers combined declined by 1.6% among African Americans each year between 1993 and 2001, the report said. That rate is greater than the 1% yearly decline seen among whites in the same period. And screening rates among African Americans have improved over the past decades.

Still, African Americans are much more likely to die from cancer than any other racial or ethnic group, and are more likely than whites to be diagnosed with more advanced disease, which is harder to treat.

Lung cancer rates are 47% higher among African-American men than white men. And although the death rate from lung cancer has been dropping among black men, it is still 36% higher than for white men. Lung cancer is expected to claim 15,500 lives among African Americans in 2005, making it the leading cancer killer in this group.

Colon cancer rates are also higher among African Americans than whites, for both men and women. And although death rates from the disease have dropped, the decline has been greater among whites. Colon cancer is the third leading cause of cancer death among both African-American men and women. It is expected to kill about 7,080 African Americans in 2005.

Breast cancer is the most common cancer among African-American women, and the second leading cause of cancer death. About 19,240 new cases are expected this year. This cancer is actually less common among African-American women than white women -- except in the case of women under 40; younger black women have higher rates of the disease than do younger white women. But even though African-American women overall are less likely to get breast cancer, they are more likely to die from it. About 5,640 black women are expected to die of breast cancer this year.

Perhaps the greatest disparity occurs in prostate cancer. Rates of this cancer are 60% higher in African-American men than white men and death rates are nearly two-and-a-half times higher. About 30,770 prostate cancer cases and 5,050 deaths are expected in 2005, making this disease the most common cancer and the second leading cause of cancer death in black men.

How to account for these striking differences? Numerous factors may be involved, the report says.

Poverty is certainly one reason. African Americans make up about 13% of the US population, but 24% of the nation's poor. This may lead to lower quality health care that in turn leads to later diagnosis and a worse outcome.

Lifestyle may also be a factor. Smoking is more common among African-American men than white men, which may help explain the differences in lung cancer cases and deaths. Being overweight or obese, which can raise the risk of many cancers, is more common in African-American women than white women. And overall, blacks are less physically active than whites; getting enough exercise can lower the risk of some cancers.

"The fact is, African Americans have not benefited equally from the improvements that are making a difference," said Durado Brooks, MD, director of prostate and colorectal cancers at the American Cancer Society. "We need to do more to improve the socioeconomic factors and to educate people about the lifestyle factors that can help further lessen the unequal burden on African Americans."