| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Malpractice Issues in Radiology |
1 Department of Radiology, Rush North Shore Medical Center, 9600 Gross Point Rd., Skokie, IL, and Rush Medical College, Chicago, IL.
Received March 29, 2002;
accepted after revision April 3, 2002.
Case summaries are based on actual events and lawsuits, although certain
facts have been omitted or modified by the author. All opinions expressed
herein are those of the author and do not necessarily reflect those of the
American Journal of Roentgenology or the American Roentgen Ray
Society.
Case I
 Top Case I Medical—Legal IssuesCase 2Medical—Legal IssuesDiscussionSummary and Risk ManagementReferences |
|---|
There was no further contact between the patient and any personnel in the imaging center.
Twenty-three months after the CT was performed, the radiologist was served with notice that both he and the imaging center were being sued for medical malpractice by the patient's family. The legal complaint alleged that the patient had undergone CT screening at the imaging center "for the purpose of having a radiologic evaluation to determine whether coronary artery disease was present," but that the defendants "failed to accurately perform and interpret" the study. The lawsuit further alleged that the CT performed on the patient was "erroneously reported as showing a zero calcium score, when in fact the patient was suffering from extensive coronary disease." As a result of these "careless and negligent acts," charged the lawsuit, the patient died suddenly of a myocardial infarction 11 months after the CT was performed.
|
TopCase IMedical—Legal IssuesCase 2Medical—Legal IssuesDiscussionSummary and Risk ManagementReferences |
|---|
The natural history of coronary disease is such that the patient had to have had significant coronary artery occlusion at the time the CT was performed because of the fact that he suffered a fatal myocardial infarction 11 months later... and obviously the CT did not properly target the coronary arteries.
Pointing out also that the screening examination had been performed on a dual-slice helical CT scanner instead of an electron beam CT scanner, the plaintiff's radiology expert asserted that:
If the study had been performed on proper equipment and correctly interpreted, the patient's coronary arteries would have shown advanced disease.... This would have led to treatment that would have averted the later coronary event that caused the patient's death.
The attorney for the defendants retained a radiology expert who strongly disagreed with the plaintiff's expert. The defense expert testified that he had been able to load the images and score the coronary calcium using the same software used by the defendants and he was "absolutely satisfied" that the CT was "properly performed, scored, and interpreted." "The coronary calcium score is zero," he insisted. Pointing out that "it is well known that about 10% of patients with obstructive coronary disease have calcium scores of zero," and asserting that the results of dual-slice helical CT are comparable to those obtained on electron beam CT units, the defense expert concluded his testimony by stating emphatically that the defendant had "fully complied" with the standard of radiologic care.
Offers to settle the malpractice lawsuit advanced by the plaintiff were rejected by the defendants. Two weeks before trial was scheduled to begin, the plaintiff's attorney withdrew the lawsuit.
|
TopCase IMedical—Legal IssuesCase 2Medical—Legal IssuesDiscussionSummary and Risk ManagementReferences |
|---|
Fifteen months later the woman, complaining of cough, visited her physician. She gave a history of having smoked one to two packs of cigarettes daily for the past 20 years. Chest radiography revealed a lesion in the left lower lobe that was suspicious for carcinoma. The physician referred the patient to a thoracic surgeon, additional testing was ordered that confirmed the presence of carcinoma, and the patient underwent a pneumonectomy followed by chemotherapy. Her condition steadily deteriorated and she died 12 months after surgery.
Three months before her death, the woman and her family sued the radiologist who had interpreted the initial CT screening, alleging negligence in his "failure to observe a malignant nodule in the patient's left lower lobe." The hospital was named a codefendant.
|
TopCase IMedical—Legal IssuesCase 2Medical—Legal IssuesDiscussionSummary and Risk ManagementReferences |
|---|
The defense attorney arranged to have the CT scan reviewed by two other radiologists, both of whom agreed that the suspicious-looking nodule was present and should have been observed by the defendant radiologist. Neither could offer support for the defendant.
With the consent of the two codefendants, the radiologist's insurance company and the hospital entered into negotiations with the plaintiff's attorney to settle the lawsuit. The parties eventually agreed to a $1 million settlement, 90% of which was paid on behalf of the radiologist.
|
TopCase IMedical—Legal IssuesCase 2Medical—Legal IssuesDiscussionSummary and Risk ManagementReferences |
|---|
Heart CT and Coronary Artery Calcification
Although calcifications occurring in the walls of coronary arteries have
been recognized as markers of coronary atherosclerosis for 40 years, it was
not until 1989 that electron beam CT was first used for visualization of
coronary artery calcification
[4]. As more studies were
published correlating the quantity of coronary artery calcification with the
degree of coronary atherosclerosis, electron beam CT began to be used as a
screening test for coronary disease.
By the early 1990s, an "entire industry based on the argument that CT scans can foretell whose life will end in a fatal heart attack" emerged, according to a Wall Street Journal article tracing the history of the procedure [5]. Radio and newspaper advertisements began appearing that exhorted middle-aged men and women to "trade blissful ignorance for certain knowledge of their cardiac health" by undergoing CT screening of their coronary arteries [6]. In 2002, the Wall Street Journal estimated that 400,000 Americans underwent CT screening of the heart, a 20% jump from the year before. The president of a CT screening company traced a recent abrupt surge in the public's clamor for heart scans to October 2, 2000, the day the test was publicized by television talk show personality Oprah Winfrey. On the day after the Winfrey show, according to the Journal, "scanning companies all over the country were besieged." The president of a Florida-based CT scanning company was quoted as saying, "We had 500-600 phone calls the next day...it was insane. People went nuts" [5].
Even before the publicity generated by the Winfrey show, newspapers and magazines began profiling CT heart scanning, sometimes in sensational ways. In a "health journal" article published in the Wall Street Journal in 1998 [6], a 45-year-old man who had "silent" cardiac disease was quoted as saying, "I would be dead right now...if I hadn't heard the heart scan commercial on the Rush Limbaugh show." Another article on heart scanning published in Newsweek magazine stated that "The new scan can detect heart disease at its earliest and most treatable stages.... It could become as common as mammography, and equally effective at saving lives" [7].
The screening of asymptomatic individuals using electron beam CT for the purpose of identifying those at high risk for developing obstructive coronary heart disease began in the United States and other countries about a dozen years ago [8]. The rationale for CT screening of the heart is based on the recognition that a strong relationship exists, as evidenced by numerous research and autopsy studies, between the presence of occlusive coronary artery disease and coronary artery calcification [9]. The prevailing belief is that the quantity of calcified plaque acts as an indicator of the presence and amount of soft, relatively unstable plaque, the type most likely to rupture and cause myocardial infarction [4, 10]. The sensitivity of CT heart screening for occlusive disease has been estimated to be approximately 94%, the specificity, 72% [9]. Preliminary findings suggest that the presence of coronary calcium is indicative of a 4.2 overall relative risk of having a future cardiac event [11].
The absence of coronary artery calcification is associated with a very low risk of future serious cardiac events. The negative predictive value of a CT screening examination for "significant" coronary artery disease has been estimated to be 90-95% [4]. Various researchers have suggested that CT examination of the heart is particularly useful in evaluating otherwise healthy patients complaining of acute chest pain. In one study of patients admitted to hospital emergency departments with chest pain, it was found that the risk of immediate myocardial infarction in patients who had negative findings on heart CT was negligible, and the future annual rate of a serious cardiac event was well below 1% [12]. Shemesh et al. [13] found a negative predictive value of 92%. However, in a more recent report, Shemesh found that although patients who score low on heart CT do have a low rate of serious myocardial events compared with those who score high, cardiac events in patients who score low, when they do occur, are apt to be catastrophic [14]. Shemesh believes that the relationship between coronary artery calcium and the risk of a fatal heart attack is more complex than was previously assumed (Shemesh J, presented at Radiological Society of North America meeting, December 2001).
Electron Beam CT Versus MDCT
The first report describing a quantification method for evaluating coronary
artery calcification, and most similar reports that followed in the early
1990s, used electron beam CT
[15]. In 1995, Shemesh et al.
[13] reported that studies
using an Israeli-manufactured dual helical CT scanner showed results
comparable to those achieved by electron beam CT. Since that time, additional
studies have been published that compare electron beam CT with MDCT. Goldin et
al. [16] compared the
quantification and reproducibility of coronary artery calcification measured
by electron beam CT with that measured by helical CT. Those researchers found
that electron beam CT was more accurate than single-detector helical CT, but
they obtained no data regarding MDCT. More recently, Becker et al.
[15] found excellent agreement
between MDCT and electron beam CT and concluded that both types may be
considered screening tools for coronary artery disease. Carr et al.
[17] also found that currently
manufactured "fast" helical CT scanners are comparable to electron
beam CT in measuring coronary calcification.
An American College of Cardiology—American Heart Association expert consensus document on the diagnosis and prognosis of coronary artery disease published in July 2000 summarized the status of CT heart screening as follows [8]:
We can conclude from this brief discussion that coronary artery calcification is a marker of coronary occlusive disease and that CT screening of the heart by means of either electron beam CT or MDCT will accurately detect the presence of calcium. Patients with detectable calcium will have a greater likelihood of undergoing future cardiac events. Conversely, patients who show no calcium have a low probability of undergoing a cardiac event. Nevertheless, the following important medical—legal caveat must be emphasized: As stated by the defense radiology expert witness in case 1 described at the beginning of this article, as many as 10% of screened patients with no demonstrable calcium may suffer a perhaps severe and possibly fatal myocardial infarction. It is likely that the plaintiff patient described in case 1 was in that 10%.
CT Screening and Lung Cancer
Probably no single scientific report electrified and mobilized the
radiology community into action more than did the study of Claudia Henschke et
al. [18] that heralded the use
of CT screening in detecting early lung cancer. The report, summarizing the
preliminary findings of the group's Early Lung Cancer Action Project, was
published in the July 10, 1999, issue of Lancet but had already hit
the front page of the The New York Times the day before
[19]. Under the headline,
"CAT Scan Process Could Cut Deaths from Lung Cancer: Small Tumors
Detected; Study Shows Routine X-Rays and Other Tests Fail To Find Growths
Early Enough," the Times article reported that the Henschke
group found that helical CT conducted in 1000 people who were smokers or
former smokers, age 60 years or older, identified 27 lung cancers, 23 of which
were stage I. Corresponding chest radiographs had identified only four stage I
cancers. "We're saying that we could change survival from 12-15% to
80%," Henschke was quoted as enthusiastically proclaiming.
One day later The New York Times published a follow-up article. Under the headline, "Cancer Study Prompts Surge in Desire for CAT Scans," the Times reported that the Mayo Clinic had received more than 3000 telephone calls requesting chest CT scans, a "demand for appointments [that] far exceeds our capacity," according to Stephen Swensen, Mayo's chair of radiology [20]. Two months later, McCalls magazine featured an article on lung cancer that highlighted the use of CT screening to detect early lung cancer [21]. In the following months, Family Circle magazine chimed in with a lead article on lung cancer [22] that stated:
A safe and painless 20-second exam could save your life by detecting lung cancer early. The test, called low-dose computed tomography (CT), can find lung tumors long before they appear on traditional X-rays.
Not unexpectedly, hospital-based radiology departments and outpatient imaging centers soon began advertising CT lung screening as a means to reduce death by lung cancer through early detection. The push was on. In the 3.5 years that have passed since the publication of the initial study by Henschke et al. [18], numerous reports and commentaries on the role of CT in the detection of early lung cancer have been published, some supportive, others urging caution. Articles in the American Medical News [23] and The Wall Street Journal [24] published early in 2000 expressed reservations about the procedure. Emphasizing the need for further investigation to confirm the value of CT screening for lung cancer, one researcher lamented, "CT scans have become an entrepreneurial pursuit" [23]. Referring to a New York City university hospital's advertisement that boasted, "Find Lung Cancer When It's the Diameter of a Cigarette," a Wall Street Journal article [24] admonished that although some researchers have hailed CT as a "breakthrough in the battle against one of the deadliest forms of cancer," others have warned that there is as yet no proof that CT leads to successful early treatment. A university radiologist specializing in thoracic imaging cautioned, "You may live longer with the diagnosis, but you number is still up at the same time."
Writing in an October 2000 issue of the Journal of the American Medical Association, internist Paul Frame [25] called attention to several potential harmful effects resulting from lung cancer CT screening. These effects included complications from biopsies required for false-positive findings, morbidity and mortality of surgery performed for questionably malignant or minimally malignant lesions, and excessive radiation exposure due to multiple high-resolution CT follow-up examinations required for patients in whom tiny noncalcified nodules are found. Frame then concluded:
I believe it should be ethical for physicians to discuss lung cancer screening with selected high-risk patients. As long as the patient understands that screening is no substitute for tobacco avoidance, understands that it is not known whether screening leads to better outcomes, understands screening may lead to a cascade of further evaluations and potential complications, and is aware that third-party payers may not pay for the test, it is appropriate for physicians to offer screening if that is what the patient desires.
Also advising caution was a group of researchers at Duke University and Roswell Park Cancer Institute [26]. Referring to lead-time, length-time, and overdiagnosis biases, those researchers pointed out that a reduction in mortality rates, rather than a lengthening of 5-year survival rates, is necessary to validate potential screening methods. Those researchers reviewed previous studies conducted in the 1950s-1970s that evaluated the efficacy of routine chest radiography in detecting early lung cancer. They summarized those studies as disclosing that although the number of early-stage lung cancers was greater and survival rates were higher in the screened groups, no clear reduction was seen in mortality from lung cancer. The researchers explained that some lung cancers are very aggressive and that even close surveillance and early detection will not affect the outcome. Furthermore, some patients with small primary lesions already have metastases at the time of "early" detection. Acknowledging that the results of early trials evaluating CT lung screening have confirmed that CT is more sensitive than conventional chest radiography for the detection of lung nodules, and that more patients screened by CT have resectable early-stage disease, the Duke—Roswell researchers nevertheless cautioned that the size of the nodule at diagnosis does not necessarily correlate with the clinical outcome. No data confirm that a primary 5-mm lung tumor has a significantly better prognosis than a 10-mm tumor, they explained. "Too often, presumed solutions have prematurely become standard medical care before the appropriate studies have been completed," concluded these scientists. "Until these trials clearly confirm a reduction in mortality from lung cancer, only carefully monitored studies should enroll patients for lung-cancer screening."
Opposing "pro" and "con" editorials published in 2001 addressed the role of CT in lung cancer screening. A Mayo Clinic pulmonologist took the affirmative position and supported such endeavors [27]:
Spiral CT scanning for lung cancer is the single most exciting new development in lung cancer that I have witnessed in my 20-year career.... I would recommend spiral CT scanning screening for my brother or sister if he or she were a current or former smoker.
In the opposing editorial, Duke University radiologists Edward Patz and Philip Goodman [28] contended that because there are still no mortality data to confirm that CT screening is effective in saving the lives of patients afflicted with lung cancer, "We should not adopt unproven practices without the appropriate confirmatory data. Mass CT screening for lung cancer is not ready for prime time."
Others have expressed similar doubts regarding the value of CT screening for lung cancer. A recent New York Times article on the subject quoted Mayo Clinic radiology chair Stephen Swensen as stating. "People who undergo spiral CT lung scans for detection of lung cancer probably assume that this could save their lives, but that is absolutely, unequivocally unproven" [29]. Robert Stanley, radiology chair at the University of Alabama, echoed similar sentiments: "People think that the early detection of cancer is absolutely and unequivocally a good thing, but even when a test detects cancer, the discovery may not be life-saving" [29]. Others have expressed similar reservations [11, 30].
The relationship between size and stage of lung cancers and mortality rates was addressed in a study conducted at Duke University [31]. Those researchers could not find a statistically significant relationship between the size and the stage of cancer at the time of presentation, and reduction in mortality. "Although it is reassuring to believe...that lung carcinoma screening can reduce mortality, to our knowledge there are no conclusive data to support this belief," concluded those researchers. Others have also echoed the sentiment that finding lung cancers that are very small may not mean that the prognosis is any better [32]. A group of German researchers recently reported that CT screening found small asymptomatic lung cancers, most of which were in an early stage, in 1.3% of a smoking population. However, those researchers, too, concluded that [33]:
Although low-dose CT appears to be much more sensitive for detecting small pulmonary nodules representing lung cancer, this does not automatically translate into reduction of lung cancer mortality.
Although many recently reported studies seem to raise doubt about the efficacy of CT lung screening in reducing mortality from lung cancer, some do not. An example is the recently published Japanese study that found that patients whose lung carcinomas were discovered with CT screening have an overall survival rate of 71%, about twice as high as those whose carcinomas were not diagnosed by screening [34, 35].
The most recently released data, as of the writing of this article, from the National Institutes of Health—sponsored trial of CT lung cancer screening disclose an 80% false-positive rate. This has led some investigators to "question the diagnostic value of this controversial test," according to a recent report [36]. The report quotes one researcher participating in the project as observing:
Eighty percent of our participants have a positive finding, and the vast majority of those findings are false positives.... No one should be routinely screened either with low-dose CT or chest radiography outside of a study protocol. No medical society recommends screening for lung cancer with CT or chest x-ray because these techniques are still unproven to save lives.
The National Institutes of Health CT lung cancer screening project continues and more data will be forthcoming.
Let us return to the allegation in case 2—namely, that the radiologist missed the early carcinoma on the initial CT screening examination. Although we have thus far in this article focused primarily on the ramifications of false-positive findings on CT lung screenings, the issue of false-negative findings has drawn little attention. It is an issue worthy of note, however.
Although the miss rate of carcinomas and other lesions on conventional chest radiography has been extensively discussed in the literature [37], the subject of the miss rate on chest CT has not received much notice. Nonetheless, one excellent study of missed lesions on chest CT has been published. White et al. [38] wrote a fascinating analysis of small lung carcinomas overlooked on CT. Those researchers first reviewed previously published studies that indicated that in as many as 90% of patients with radiographic evidence of lung cancer, the tumor is visible on retrospective review of chest radiographs that were previously obtained but interpreted as showing normal findings. White et al. then focused on missed carcinomas on chest CT, noting that 73% of the missed lesions were located in a lower lobe. The researchers attributed many of these missed lesions to lack of conspicuity and technical factors such as partial volume averaging and misregistration. The most fascinating part of their study was the fact that the White group's consultant, an experienced thoracic radiologist, even knowing prospectively that each CT scan in the study group included a missed cancer, was able to identify the missed lesion in fewer than half the cases. These findings should generate considerable introspection if not concern in those radiologists who sponsor high-profile advertisements claiming, either explicitly or implicitly, that patients who undergo CT lung screening will have every tiny carcinoma detected. Certainly some small carcinomas will be missed.
What is the current status of CT screening for early lung cancer? Claudia Henschke and Nestor Muller, speaking at the annual meeting of the Radiological Society of North America in 2001, concluded that mass screening is not recommended, further studies are required to validate the usefulness of CT screening, and prospective lung screening trials should be encouraged [39]. In a statement expressing its official position on the subject, the American College of Radiology acknowledges that preliminary findings of CT screening for lung cancer indicate [11]
...encouraging results, which have renewed the enthusiasm for low-dose screening CT, but, nevertheless, screening for lung cancer, as with other diseases, includes a number of complex and controversial issues...Caution in promoting CT screening...is [recommended].
A physician, Barron Lerner, writing in The New York Times, summarized the present status of CT screening for lung cancer in this manner [40]:
Spiral CT scanning of the lungs epitomizes the dilemma that plagues modern cancer screening. Through Pap testing and screening for colonic polyps, doctors can successfully prevent cervical and colon cancers. These situations underscore the value of early detection, which has long been the gospel of cancer control. But in [other cases,] our ability to discover early-stage tumors or other suspicious lesions is of less-clear value. In some instances, we are clearly discovering slow-growing cancers that will never actually kill the patient, or rapidly growing cancers that have already spread and are thus not early at all.Given that we may never have definitive proof of the value of spiral CT scanning, as in the case with PSA [prostate-specific antigen] testing or mammography, the decision to be screened will still come down to the individual patient's weighing the pros and cons. Should a patient dare to decline a scan that might discover an early, curable cancer? Should a patient risk the possibility of major surgery for a "cancer" that turns out to be benign?
The answers to these questions are yet to be determined.
|
TopCase IMedical—Legal IssuesCase 2Medical—Legal IssuesDiscussionSummary and Risk ManagementReferences |
|---|
Risk management in radiology can lessen the likelihood of incurring a medical malpractice lawsuit and maximize the chance for a successful defense if a suit is filed, while at the same time enhancing patient care. The following risk-management pointers will help meet all three of these objectives in light of the potential liability resulting from performing CT screening.
|
TopCase IMedical—Legal IssuesCase 2Medical—Legal IssuesDiscussionSummary and Risk ManagementReferences |
|---|
3 cm) primary nonsmall cell lung carcinoma:
implication for lung carcinoma screening. Cancer
2001;92:3051
-3055[Medline]
CiteULike 
Complore 
Connotea 
Del.icio.us 
Digg 
Reddit 
Technorati What's this?
This article has been cited by other articles:
|
|
 |
|
  H. Schoder and M. Gonen Screening for Cancer with PET and PET/CT: Potential and Limitations J. Nucl. Med., January 1, 2007; 48(1_suppl): 4S - 18S. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. D. Furtado, D. A. Aguirre, C. B. Sirlin, D. Dang, S. K. Stamato, P. Lee, F. Sani, M. A. Brown, D. L. Levin, and G. Casola Whole-Body CT Screening: Spectrum of Findings and Recommendations in 1192 Patients Radiology, November 1, 2005; 237(2): 385 - 394. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 F. M. Hall and L. F. Rogers CT Screening Examinations Am. J. Roentgenol., April 1, 2003; 180 (4): 1178 - 1179. [Full Text] [PDF]
|
|
|
|
|
|
L. Berlin Should Whole-Body CT Screening Be Performed with Contrast Media? Am. J. Roentgenol., February 1, 2003; 180(2): 323 - 325. [Full Text] [PDF]
|
|
|
|
|
|
L. Berlin Liability for Failure to Order Screening Examinations Am. J. Roentgenol., December 1, 2002; 179(6): 1401 - 1405. [Full Text] [PDF]
|
|
|
|
|
|
L. F. Rogers Whole-Body CT Screening: Edging Toward Commerce Am. J. Roentgenol., October 1, 2002; 179(4): 823 - 823. [Full Text] [PDF]
|
|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
