Screening CT: rationale

Screening in the dark: ethical considerations of providing screening tests to individuals when evidence is insufficient to support screening populations

During the past decade, screening tests using computed tomography (CT) have disseminated into practice and been marketed to patients despite neither conclusive evidence nor professional agreement about their efficacy and cost-effectiveness at the population level. This phenomenon raises questions about physicians' professional roles and responsibilities within the setting of medical innovation, as well as the appropriate scope of patient autonomy and access to unproven screening technology. This article explores how physicians ought to respond when new screening examinations that lack conclusive evidence of overall population benefit emerge in the marketplace and are requested by individual patients. To this end, the article considers the nature of evidence and how it influences decision-making for screening at both the public policy and individual patient levels. We distinguish medical and ethical differences between screening recommended for a population and screening considered on an individual patient basis. Finally, we discuss specific cases to explore how evidence, patient risk factors and preferences, and physician judgment ought to balance when making individual patient screening decisions.

Patient Expectations of Full-Body CT Screening

OBJECTIVE

Despite limited scientific evidence about its risks and benefits, full-body CT screening is available to self-referred individuals. The purpose of this study was to develop a scientific knowledge base about patient expectations of the procedure and to determine whether characteristics of patients influence their expectations of its health benefits.

MATERIALS AND METHODS

Facilities from six diverse, geographically representative U.S. regions performing full-body CT screening were used as the study sites. A pretest only descriptive survey design was used to study 94 patient volunteers scheduled to undergo full-body CT screening. Descriptive statistics were used in examining information about the demographics, health, and knowledge characteristics of the patients. The chi-square test for independence and Spearman's correlation coefficient for ranked data were used to analyze associations among patient characteristics and responses to expectation statements. An alpha value of 0.05 was the level of significance.

RESULTS

Survey participants were 35-65 years old, predominantly white, married, and health conscious with income and educational levels several times above the national averages. The patients' highest expectations related to consumer empowerment and their lowest expectations related to the limitations of the procedure. The five patient characteristics found to have significant associations with patient expectations were patient sex; referral method; level of personal health concern; number of other health screening procedures patient had undergone; and patients' self-estimations of their current health status.

CONCLUSION

This study provided quantitative and descriptive data that are consistent with and add to the existing, primarily anecdotal, knowledge base about patients' expectations of full-body CT screening. These findings can be used to educate patients before they provide informed consent for the procedure.

Periampullary and pancreatic incidentaloma: a single institution's experience with an increasingly common diagnosis

BACKGROUND

While incidental masses in certain organs have received particular attention, periampullary and pancreatic incidentalomas (PIs) remain poorly characterized.

METHODS

We reviewed 1944 consecutive pancreaticoduodenectomies (PD) over an 8-year period (April 1997 to October 2005). A total of 118 patients (6% of all PDs) presented with an incidental finding of a periampullary or pancreatic mass. The PI patients were analyzed and compared with the rest of the cohort (NI, nonincidentaloma group, n = 1826).

RESULTS

Thirty-one percent of the PI patients (n = 37) had malignant disease (versus 76% of the NI patients, P < 0.001), 47% (n = 55) had premalignant disease, and the remaining 22% (n = 26) had little or no risk for malignant progression. The 3 most common diagnoses in the PI group were IPMN without invasive cancer (30%), cystadenoma (17%), and pancreatic ductal adenocarcinoma (10%). The PI group had a higher overall complication rate (55% versus 43%, P = 0.02), due in part to a significantly increased rate of pancreatic fistulas (18.4% PI versus 8.5% NI, P < 0.001). Patients in the PI group with malignant disease had a superior long-term survival (median, 30 months, P = 0.01) compared with patients in the NI group with malignant disease (median, 21 months).

CONCLUSIONS

Incidentally discovered periampullary and pancreatic masses comprise a substantial proportion of patients undergoing PD. Roughly three fourths of these lesions are malignant or premalignant, and amenable to curative resection. Resected malignant PIs have favorable pathologic features as compared with resected malignant NIs, and resection of these early lesions in asymptomatic individuals is associated with improved survival, compared with patients with symptomatic disease.

Whole-body CT screening: spectrum of findings and recommendations in 1192 patients

PURPOSE

To retrospectively determine the frequency and spectrum of findings and recommendations reported with whole-body computed tomographic (CT) screening at a community screening center.

MATERIALS AND METHODS

This HIPAA-compliant study received institutional review board approval, with waiver of informed consent. The radiologic reports of 1192 consecutive patients who underwent whole-body CT screening of the chest, abdomen, and pelvis at an outpatient imaging center from January to June 2000 were reviewed. Scans were obtained with electron-beam CT without oral or intravenous contrast material. Reported imaging findings and recommendations were retrospectively tabulated and assigned scores. Descriptive statistics were used (means, standard deviations, and percentages); comparisons between subgroups were performed with univariate analysis of variance and chi(2) or Fisher exact tests.

RESULTS

Screening was performed in 1192 patients (mean age, 54 years). Sixty-five percent (774 of 1192) were men and 35% (418 of 1192) were women. Nine hundred three (76%) of 1192 patients were self referred, and 1030 (86%) of 1192 subjects had at least one abnormal finding described in the whole-body CT screening report. There were a total of 3361 findings, with a mean of 2.8 per patient. Findings were described most frequently in the spine (1065 [32%] of 3361), abdominal blood vessels (561 [17%] of 3361), lungs (461 [14%] of 3361), kidneys (353 [11%] of 3361), and liver (183 [5%] of 3361). Four hundred forty-five (37%) patients received at least one recommendation for further evaluation. The most common recommendations were for additional imaging of the lungs or the kidneys.

CONCLUSION

With whole-body CT screening, findings were detected in a large number of subjects, and most findings were benign by description and required no further evaluation. Thirty-seven percent of patients had findings that elicited recommendations for additional evaluation, but further research is required to determine the clinical importance of these findings and the effect on patient care.

Dark lumen magnetic resonance colonography: comparison with conventional colonoscopy for the detection of colorectal pathology

BACKGROUND

The purpose of this study was to assess the feasibility and usefulness of a new magnetic resonance (MR) colonography technique for the detection of colorectal pathology in comparison with conventional colonoscopy as the standard of reference.

PATIENTS AND METHODS

A total of 122 subjects with suspected colorectal disease underwent "dark lumen" MR colonography. A contrast enhanced T1w three dimensional VIBE sequence was collected after rectal administration of water. The presence of colorectal masses and inflammatory lesions were documented. Results were compared with those of a subsequently performed colonoscopy.

RESULTS

MR colonography was found to be accurate regarding detection of clinically relevant colonic lesions exceeding 5 mm in size, with sensitivity and specificity values of 93%/100%.

CONCLUSION

Dark lumen MR colonography can be considered as a promising alternative method for the detection of colorectal disease. In addition, it allows assessment of extraluminal organs.