Interval colorectal cancer accounts for 3% to 8% of all cases of colorectal cancer in the United States. Data on interval colorectal cancer by race/ethnicity are scant.
Dr Stacey Fedewa and colleagues from Pennsylvania, USA examined whether risk for interval colorectal cancer among Medicare patients differs by race/ethnicity and whether this potential variation is accounted for by differences in the quality of colonoscopy, as measured by physicians' polyp detection rate.
The team evaluated patients aged 66 to 75 years who received colonoscopy between 2002 and 2011 and were followed through 2013.
There were 2735 cases of interval colorectal cancer identified over 235,146 person-years of follow-up.
The research team observed a higher proportion of black persons than white persons received colonoscopy from physicians with a lower polyp detection rate.
|The disparity was more pronounced for cancer of the rectum|
|Annals of Internal Medicine|
The team noted that this rate was significantly associated with interval colorectal cancer risk.
The researchers found that the probability of interval colorectal cancer by the end of follow-up was 7% in black persons and 6% in white persons.
Compared with white persons, black persons had significantly higher risk for interval colorectal cancer.
The team reported that the disparity was more pronounced for cancer of the rectum, and distal colon than for cancer of the proximal colon.
Adjustment for polyp detection rate did not alter hazard ratios by race/ethnicity, but differences between black persons and white persons were greater among physicians with higher polyp detection rate.
Dr Fedewa's team comments, "Among elderly Medicare enrollees, the risk for interval colorectal cancer was higher in black persons than in white persons."
"The difference was more pronounced for cancer of the distal colon and rectum and for physicians with higher polyp detection rates."