Colorectal cancer is the third most common form of cancer and the second most common cause of cancer deaths in the United States. The chance of developing colorectal cancer increases with age. Now, a study by University of Missouri School of Medicine researchers shows that minority and ethnic groups are being diagnosed with colorectal cancer at younger ages and more advanced stages than non-Hispanic whites.

"While we know the risk of developing colorectal cancer increases with age, little is known about its prevalence within various minority and ethnic groups," said Jamal Ibdah, M.D., Ph.D., a professor of medicine and Raymond E. and Vaona H. Peck Chair in Cancer Research at the MU School of Medicine and lead author of the study. "Hispanic, Asian, Pacific Islander, American Indian, Alaska Native and African-American populations are the fastest-growing racial and ethnic minority groups in the United States. Having the most accurate statistical data is critical to providing cancer prevention and control programs for these groups."

Ibdah's research team used the databases Surveillance, Epidemiology and End Results (SEER) and the North American Association of Central Cancer Registries (NAACCR) to analyze the prevalence, stage and survival rates for colorectal cancer diagnoses in the U.S. based on race and ethnicity from 1973 to 2009.

"We found that minorities under the age of 50 were twice as likely to be diagnosed with colorectal cancer compared to non-Hispanic whites," said Ibdah, who also serves as director of the Division of Gastroenterology and Hepatology at the MU School of Medicine. "On average, minorities were diagnosed between the ages of 64 and 68, while non-Hispanic whites were typically diagnosed at age 72. When diagnosed, minority groups also had more advanced stages of cancer."

Ibdah said that several issues could influence the development of colorectal cancer at a younger age, such as hereditary and environmental factors, diet and lifestyle. Possible reasons for advanced stage diagnosis among minorities may include lower screening rates, lower income levels, and reduced access to education and health care.

"Regular screening for colorectal cancer is essential for prevention and early diagnosis," Ibdah said. "Our findings suggest a need for further studies to examine current guidelines for all minority groups in the U.S. and the development of possible new interventional strategies."