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Archived: This report is greater than 3 years old. Findings may be used for research purposes, but should not be considered current.
Our objectives were to synthesize the available information on the diagnostic accuracy and clinical utility of commonly used imaging tests for the diagnosis and staging of pancreatic adenocarcinoma, as well as screening for pancreatic adenocarcinoma in high risk individuals.
We searched Embase, MEDLINE, PubMed, and The Cochrane Library from 1980 through November 1, 2013, for English-language, full-length articles on the role of multidetector computed tomography (MDCT), endoscopic ultrasound with fine-needle aspiration (EUS-FNA), magnetic resonance imaging (MRI), and positron emission tomography–computed tomography (PET/CT) in screening, diagnosis, and staging pancreatic adenocarcinoma. The searches identified 9,776 citations; after screening against the inclusion criteria, we included 15 systematic reviews and 108 primary studies.
We extracted data from the included studies and constructed evidence tables. Comparative outcomes of interest included diagnostic accuracy (sensitivity and specificity), staging accuracy, screening accuracy, clinical management, quality of life, survival, and harms of imaging tests. For studies of a single imaging test, the key outcomes were accuracy and procedural harms. Where possible, we pooled the data using bivariate binomial regression models for comparative accuracy. For each pair of tests and each assessed aspect (e.g., determination of metastases), we determined whether the evidence was sufficient to permit a conclusion of a difference, a conclusion of similar accuracy, or neither (i.e., insufficient). We rated the risk of bias of individual studies using an internal validity instrument and graded the overall strength of evidence of conclusions using Evidence-based Practice Center methods. For data on single-test accuracy, procedural harms, patient tolerance, and screening accuracy, we tabulated the important information and summarized the evidence qualitatively.
We included 15 systematic reviews and 108 primary studies. Regarding comparative accuracy, the evidence was sufficient to conclude that MDCT and EUS-FNA have similar accuracy in assessing resectability in patients whose disease is unstaged, and that EUS-FNA has a slight advantage over MDCT with respect to T (tumor) staging (specifically, a lower chance of undersizing the tumor). Further, we concluded that MDCT and MRI are similarly accurate with respect to both diagnosing and assessing vessel involvement. For PET/CT, evidence was generally inconclusive, but we found low-strength evidence to conclude that PET/CT is more accurate than MDCT in assessing distant metastases (slight advantages in both sensitivity and specificity). None of the included studies reported comparative data on clinical management, survival, quality, or the impact on comparative accuracy of patient characteristics, tumor characteristics, or operator experience. Many studies have reported procedural harms, but harms are generally rare and are different for different imaging modalities. In the screening of people at high risk of developing pancreatic adenocarcinoma, available studies do not correlate the results of a given imaging test to subsequent diagnoses.
Current evidence permits some tentative conclusions about the comparative assessment of imaging tests for diagnosing and staging pancreatic adenocarcinoma, but many gaps remain. The conclusions we did draw are as follows: MDCT and EUS-FNA have similar accuracy in assessing resectability in patients whose disease is unstaged; EUS-FNA has a slight advantage over MDCT with respect to T (tumor) staging (specifically, a lower chance of undersizing the tumor); MDCT and MRI are similarly accurate with respect to both diagnosing and assessing vessel involvement; and PET/CT is more accurate than MDCT in assessing distant metastases (slight advantages in both sensitivity and specificity). The prominent gaps include minimal information on MDCT angiography, imprecise data on other imaging techniques, a lack of comparative data on patient-oriented outcomes and factors that could influence comparative accuracy, and test-specific data on screening accuracy.