A significant number of physicians would recommend colorectal cancer screening for elderly patients with a severe illness, according to David Haggstrom from the Richard L. Roudebush VA Medical Center in Indianapolis in the US and his team. Such patients would not benefit from the procedure and, in fact, unnecessary screening may do more harm than good. Their work appears online in the Journal of General Internal Medicine.
Medical evidence does not indicate that colorectal cancer screening has any benefit among patients with limited life expectancy. Although guidelines recommend screening for patients aged 50 years and older, elderly patients with severe illnesses are unlikely to benefit from early cancer detection.
Haggstrom and colleagues explored whether colorectal cancer screening decisions are influenced by the patient's age and state of health. They surveyed 1,266 physicians - a mix of general internal medicine, family practice and obstetrics-gynecology physicians - between September 2006 and May 2007. The physicians were given nine patient scenarios that varied the patient's age and existing illness. Patient age was split into three categories: age 50, 65 and 80. There were three underlying illness states: healthy patient with no illness; patient with moderately severe illness (ischemic cardiomyopathy*); and patient with severe illness (advanced lung cancer). For each vignette, the physicians were asked which screening test they would recommend, if any.
Overall, the more serious the underlying illness, the less likely physicians were to recommend screening. The likelihood of recommending screening also fell with a patient's advancing age. In addition, the healthier the patient, the more likely physicians were to recommend more invasive screening e.g. colonoscopy versus non-invasive tests such as fecal occult blood testing (FOBT).
However, 25 percent of primary care physicians recommended colorectal cancer screening for an 80-year-old patient with advanced lung cancer who would not benefit.
Interestingly, physicians who were obstetrics-gynecology physicians were more likely to recommend colorectal cancer screening for 80-year-old patients with advanced lung cancer than other physicians. Physicians who had access to electronic medical records were less likely to recommend screening of elderly patients with severe illness.
The authors conclude: "Most physicians appear to shift their recommendations in an appropriate manner in response to varying patient age and underlying illness. Yet there is a significant proportion of outliers who recommend screening among patients with limited life expectancy, for whom screening tests have no benefit and are potentially harmful. Further work is needed to better understand how physicians can develop more confidence in stopping screening when there is no clinical benefit, as well as quantifying the impact of over-screening with risky procedures on patient outcomes."
Haggstrom DA et al (2012). Variation in primary care physicians' colorectal cancer screening recommendations by patient age and comorbidity. Journal of General Internal Medicine; DOI: 10.1007/s11606-012-2093-6