March 13 (Bloomberg) -- The number of older Americans getting colon cancer tests rose to 61 percent in 2006, from 54 percent four years earlier, U.S. health officials reported.

People age 50 and older were less likely to get screened if they were poor, less educated, black or lacking health insurance, according to the U.S. Centers for Disease Control and Prevention in Atlanta.

Colorectal tumors are the second-leading cause of cancer deaths in the U.S. About 145,000 new cases are diagnosed each year and approximately 54,000 people die from the disease. To catch the cancer early when it is more treatable, the CDC recommends annual fecal blood screenings, enemas every 5 years, or colonoscopies once a decade.

``Although this increase is encouraging, disparities persist in colorectal cancer test use,'' the CDC said in its report. Factors contributing to some people not getting screened include ``lack of recommendation from a physician, lack of health insurance and lack of a usual source of health care.''

Colon tumors caught early can be treated by drugs including Erbitux, made by New York-based ImClone Systems Inc., and Avastin, from Genentech Inc. of South San Francisco.

Whites got recommended tests 63 percent of the time in 2006, compared with 59 percent for blacks and 56 percent for Asians, the CDC said. Fewer than half of Hispanics were screened.

Education also affected testing, with 69 percent of people with college degrees getting screenings, compared with 57 percent among those with only high school diplomas.

To contact the reporter on this story: Lisa Rapaport in New York at Lrapaport1@bloomberg.net.

Last Updated: March 13, 2008 12:34 EDT