Although it has been established that patients with few primary care doctor's office visits are less likely to receive colorectal cancer (CRC) screening, new research indicates that patients who see their physicians regularly also do not receive screening, according to a study published online Feb. 3 in Cancer Epidemiology Biomarkers and Prevention.

For the study, which was conducted by a team of researchers at th University of California (UC) Davis Health System and the University of Washington and Group Health Cooperative in Seattle, researchers reviewed records of nearly 50,000 men and women aged 50 to 78 who were eligible for colorectal cancer screening in 2002 and 2003 and enrolled in Group Health Cooperative-a large, prepaid, nonprofit health plan that coordinates care and coverage in Washington state.

The authors said that it is estimated that there were 148,810 people diagnosed with ,and 49,960 deaths from, cancer of the colon and rectum in 2008. Screening for the disease contributes to reducing these numbers by leading to the early removal of polyps that could later become cancerous, according to the authors.

"Colorectal cancer screening is not on the primary care agenda as much as it should be," said lead author Joshua Fenton, MD, assistant professor of family and community medicine at UC Davis. "Opportunities are being missed."

Among 48,712 adults, ages 50 to 78 years, who were eligible for CRC screening under a Washington state health plan, Fenton and colleagues estimated the degree to which a lack of CRC screening in 2002 to 2003 (fecal occult blood testing, sigmoidoscopy, or colonoscopy) was attributable to low primary care use, expressed as the population attributable risk percent associated with zero to three primary care visits during the two-year period.

Based on the results, the authors concluded that "health plan outreach efforts to encourage primary care attendance would be unlikely to substantially increase population uptake of CRC screening. In similar settings, resources might be more fruitfully devoted to the optimization of screening delivery during primary care visits that patients already attend."

The study authors advocated a number of methods to increase the likelihood that colorectal cancer screening is recommended in primary care settings, including educational programs for patients and doctors, reminder systems, financial incentives and doctor's office visits dedicated to preventive care.

Fenton explained that the history of breast cancer screening, which also used to be underutilized, could serve as a model for colorectal cancer screening.

The National Cancer Institute (NCI), the American Cancer Society (ACS) and an HMO Cancer Research Network pilot grant, funded the research.