In over one third of all cases in which patients partake in a medical imaging procedure, an actual 40% display tumors or infections that are unrelated to the original need for the initial imaging. These incidental test findings are important to a patient’s health, but are there ethical dilemmas related to how and when to relay these findings to the patient, although these are key in early diagnosis, treatment and even prevention? Are assumed costs for unintentional findings acceptable? How can one be sure of these discoveries, unrelated to the original intent of the tests? A study published in the JAMA journal, Archives of Internal Medicine on September 27th discusses the research and findings related to this topic.
Nicholas M. Orme, M.D., of Mayo Clinic, Rochester and his colleagues begin:
An incidental finding in human subjects research is defined in a major consensus project as an observation concerning an individual research participant that has potential clinical importance and is discovered in the course of conducting research, but is beyond the aims of the study. Numerous reports have detailed how the detection of an incidental finding can result in the early beneficial diagnosis of an unsuspected malignant neoplasm or aneurysm. However, others describe harm and excessive cost resulting from treatment of radiographically suspicious incidental findings. Moreover, clinical experience dictates that many incidental findings are of indeterminate clinical significance and generate uncertainty among both research participants and their physicians.
Dr. Orme reviewed results of patients that had an imaging procedure in 2004. The sample size totaled 1,426 persons. Immediately and over three years post the meeting with radiology, each image was interpreted and a panel of professionals reviewed any and all incidental findings. In 567 of the images reviewed (39.8%), an incidental finding was detected and such results became more frequent with age.
Computed temography, or CT demonstrated more new ailments more frequently when scans of the stomach and pelvis were performed, closely followed by imagery procedures of the chest and MRI (magnetic resonance imaging) of the brain.
The study’s authors continue:
This study demonstrates that research imaging incidental findings are common in certain types of imaging examinations, potentially offering an early opportunity to diagnose asymptomatic life-threatening disease, as well as a potential invitation to invasive, costly and ultimately unnecessary interventions for benign processes, the majority of incidental findings seem to be of unclear significance. These instances represent a dilemma for researchers.
Results of actions taken varied. Overall, clinical action was taken for 35 (6.2 percent) of the individuals with an incidental finding. In 26 of 567, or 4.6 percent the medical benefit or burden of these actions were blurry. However, taking action did result in positive health benefit in six of the 567, or 1.1%.
It is important for practitioners to plan for these types of incidental findings and how to convey them to patients. This can raise ethical concerns related to false positives and additional costs to the public.
In related comments, Dr. Bernard Lo, of the University of California, San Francisco, who is supported by a National Institutes of Health grant from the National Center for Research Resources and NIH Roadmap for Medical Research and by the Greenwall Foundation summarizes:
In clinical research, investigators may learn information about a participant that is not pertinent to the research question but that may have important clinical implications for the participant. Such incidental findings present ethical dilemmas. Although they may offer the possibility of substantial personal benefit to the participant, more commonly they are false-positive findings that lead to a cascade of testing that presents additional risks and burdens. When planning a study, researchers need to develop a comprehensive plan for how they will respond to incidental findings, including what findings they will offer to disclose to participants. The possibility of incidental findings, and their ramifications, should be part of the informed consent process. The work by Orme et al helps us to start to quantify their impact.
Thus Orme, in taking a health first approach, finally concludes:
Timely, routine evaluation of research images by radiologists can result in identification of incidental findings in a substantial number of cases that can result in significant medical benefit to a small number of patients.
Nicholas M. Orme, MD; Joel G. Fletcher, MD; Hassan A. Siddiki, MBBS; W. Scott Harmsen, MS; Megan M. O’Byrne, MA; John D. Port, MD, PhD; William J. Tremaine, MD; Henry C. Pitot, MD; Elizabeth G. McFarland, MD; Marguerite E. Robinson, MAR, MA; Barbara A. Koenig, PhD; Bernard F. King, MD; Susan M. Wolf, JD
Arch Intern Med. 2010;170(17):1525-1532. doi:10.1001/archinternmed.2010.317
Written by Sy Kraft (B.A.)