Dr. Berlin is Chairman of the Department of Radiology at
Rush North Shore Medical Center in Skokie, IL and a Professor
of Radiology at Rush Medical College in Chicago, IL. He has
authored articles and lectured on numerous medical/legal
issues.
A recent report from the Physician Insurers Association of
America, a nonprofit organization consisting of major malpractice
insurance carriers, indicated that radiologists are the specialists
most frequently sued in malpractice lawsuits involving breast
cancer.
1
Further, the allegation that an error in the diagnosis of breast
cancer has occurred is now the most prevalent condition
precipitating medical malpractice lawsuits against all physicians.
2
While some radiologists point to a drop in the number of
malpractice cases alleging a missed mammographic diagnosis of
breast cancer as a positive trend, an increase in the average
indemnity paid in breast cancer lawsuits has become cause for
concern.
3
Accordingly, radiologists and allied professionals around the
country are taking steps to improve the accuracy of mammographic
interpretation in the belief that it will assist them in
recognizing breast cancer at its earliest stages and help reduce
mortality from the disease.
Many published articles have suggested that the accuracy rate of
mammography screening can be improved by incorporating a variety of
practices, including: continuing medical education, double
interpretation by a second radiologist, comparing current
mammograms with previous ones, establishing 2000 as the minimum
number of mammograms interpreted annually by an individual
radiologist, and the use of computer-aided detection (CAD).
4-7
Most radiologists agree that it is too early to know
definitively if any of these suggestions will improve accuracy of
interpretation, but the initial findings appear to be encouraging.
This article will provide a brief overview of one of these
practices, CAD, as well as some of the medical/legal questions that
may develop in the wake of this promising new technology.
Computer-aided detection
CAD is a sophisticated screening tool that identifies suspicious
microcalcifications and masses on mammograms. The technology is
designed to assist radiologists by providing a computerized second
review that draws their attention to subtle changes in tissue that
may indicate the presence of cancer. CAD works by digitizing an
actual mammogram, then running proprietary algorithms over the
digitized image. Once complete, highlighted areas of concern are
provided to the radiologist for further review.
CAD is not intended to replace a radiologist's interpretation,
but was designed as a computerized second opinion to be consulted
only after the radiologist completes his or her initial review of
the mammograms. The radiologist still makes the final diagnosis
after analyzing all available data and differentiating between
benign and malignant lesions.
Considering the desirability of detecting missed cancers and the
complexity of double reading, many view CAD as a viable method to
increase the sensitivity of mammographic screening. In fact,
according to a study presented at the 2000 Radiological Society of
North America meeting, CAD can find up to 20% more cancers than
screening mammography alone.
8
Medical/legal questions
While CAD has shown promise in its ability to increase the
detection rate and decrease error rate, there are a number of
medical malpractice issues associated with the technology that will
undoubtedly be the topic of many discussions as CAD systems become
more commonplace.
One of the legal uncertainties surrounding the technology
involves the ramifications of a radiologist dismissing information
provided by a CAD system. For example, what happens if the
technology marks a density that the radiologist concludes is a
false-positive finding, but months later his or her patient
develops a cancer in that highlighted area? Does the fact that the
radiologist held a different "opinion" from that of the CAD system
put the radiologist in legal jeopardy?
This leads us to another issue, perhaps the most controversial
question regarding CAD: What should radiologists do with the
results provided by the CAD system indicating potential areas of
concern? If they keep the results on file and are later faced with
a malpractice suit, they will be asked to turn over all records
pertaining to the case in question. The CAD results could then be
used against them if the cancer was indeed marked. On the other
hand, if a radiologist knowingly discards the results, his or her
motives could potentially be questioned in a court of law.
At the moment, there is no case law or federal or state
regulation regarding whether CAD results should be saved or
discarded. However, laws may eventually offer more direction on
this point.
As the use of CAD becomes more widely accepted, another question
beginning to surface is whether or not radiologists will eventually
be violating the standard of care if they don't offer and use the
technology. The law defines malpractice as "a breach of the
standard of care that causes injury to a patient."
3
So how is this standard defined? It is defined by what
reasonable and appropriate physicians in the same specialty are
doing. By extension, the standard is established from a variety of
sources, including scientific literature, seminars, testimony of
other physicians, legal decision, and by standards published by the
American College of Radiology. At the moment, it is clear that
using CAD is not the standard of care, but that could easily change
in time.
In malpractice litigation, the law takes the position that the
jury of laypeople is not familiar with the medical standard of
care. As a result, both sides in the case produce expert witnesses
who attempt to explain the standard of care and whether or not the
physician on trial breached it. Unfortunately for some
radiologists, past juries have demonstrated that they expect
physicians to be near perfect in their diagnoses, which has made
cases involving missed breast cancers difficult to defend.
Summary
Every technological breakthrough requires a period of adjustment
and adaptation for it to obtain acceptance. It would appear that
while initial studies regarding CAD have been favorable, the
technology must continue to demonstrate its value over time.
As with many innovations, CAD has both opened the door to an
exciting new frontier and has created a flood of new issues and
unanswered questions. One thing is certain, however, the
technology's ultimate influence on malpractice litigation has yet
to be seen.
AR