Update from the 2009 Gastrointestinal Cancer Symposium
African Americans in both a large national database of colorectal cancer patients and in records of a Philadelphia hospital were more likely to be diagnosed at an advanced stage and have poorer survival at every stage than white patients.
Researchers at Thomas Jefferson University in Philadephia studied information from nearly 245,000 colon and rectal cancer patients from the National Cancer Institute’s Surveillance, Epidemiology and End Results (SEER) database. They compared that information to 20 years worth of data in the Jefferson University Hospital tumor registry for 2,500 patients treated from 1988 through 2007.They looked at stage at diagnosis, location of the tumor, and its pathological grade.
In both groups of patients African Americans were more likely than white patients:
- to be diagnosed with advanced (stage III and IV) cancer
- have cancer located in the section of the colon farthest from the rectum (proximal colon)
- have worse survival, both overall and stage by stage
- have a higher likelihood that cancer had spread to nearby lymph nodes
Edith Mitchell, M.D., a medical oncologist at the Sidney Kimmel Cancer Center at Jefferson, explained,
One possible explanation could be the socioeconomic factors that are often associated with African-American patients. For example, research has shown that African-Americans are less likely than Caucasian patients to have health insurance, and thus they may not receive the screening necessary to detect colorectal cancer at an earlier stage.
However, she called for more research to pin down potential molecular or genetic factors that might further explain racial differences in colorectal cancer.
Right now, we cannot definitely explain why there are such differences between the African American and the Caucasian patients. We need to do more studies on prognostic factors related to tumor biology, molecular markers and genetics to account for the racial disparities.
Led by Dr. Mitchell, the research team concluded,
African American patients with colorectal cancer are more likely to present with later stage, more proximal tumors, and have higher nodal involvement in early stage disease disease in both NCI SEER and Thomas Jefferson University Hospital databases. Prognostic factors relative to tumor biology, molecular markers, and genetics should be studied further to account for these racial disparities.
SOURCE: Mitchell et al., 2009 ASCO GI Symposium, Abstract 306.