Fewer than half of older patients successfully treated for colorectal cancer receive the recommended screening schedule to detect any recurrence of cancer, indicating that poor compliance of the recommended monitoring of colorectal cancer survivors could affect survival, according to a study published online Sept. 8 in CANCER.
According to the researchers, patients who undergo potentially curative surgery for colorectal cancer have an increased risk of recurrence. To reduce the risk, guidelines specify a combination of regularly scheduled physician visits, colonoscopy, and other tests to detect changes that could indicate a recurrence.
While some patients may not receive these recommended services, others may undergo other procedures, such as CT and PET scans, which are generally not recommended. Therefore, the investigators found that some patients may not meet guidelines standards while others receive testing that goes beyond guideline recommendations.
Because compliance with follow-up guidelines has not been well studied, Gregory S. Cooper, MD, of University Hospitals Case Medical Center in Cleveland, and colleagues analyzed information from the Surveillance, Epidemiology and End Results (SEER) program of cancer registries and Medicare claims.
They assessed overall adherence to guidelines, as well as differences across patient subgroups, making the study the first known U.S. population-based study to examine adherence to published guidelines, the authors wrote.
The researchers included a total of 9,426 patients older than 65 who were diagnosed with adenocarcinoma of the colon or rectum from 2000-2001. Patients were followed for three years after diagnosis. The investigators considered the screening guidelines to be fulfilled if a patient received two or more office visits per year, two or more carcinoembryonic antigen tests per year, and at least one colonoscopy within three years.
Overall, Cooper and colleagues found that 60.2 percent of patients received testing below recommended levels, while fewer than 17.1 percent received testing at the recommended frequency. Nearly 22.7 percent received follow-up services above those specified by screening guidelines.
The researchers said that while some of the difference could be explained by clinical factors, such as stage of disease, they also found important differences across racial groups and region. The researchers said that the generally lower use of testing in African Americans is likely a contributing factor to the known poorer stage-specific survival compared to Caucasians. In addition, geographic differences across SEER sites suggest that patient and physician preferences may influence choice of testing.
"Further studies should ascertain the reasons for poor compliance and the effect on patient outcome," the authors wrote.