Dataset Information

Diagnostic accuracy of preoperative magnetic resonance imaging in predicting curative resection of rectal cancer: prospective observational study.

ABSTRACT:

Objective

To assess the accuracy of preoperative staging of rectal cancer with magnetic resonance imaging to predict surgical circumferential resection margins.

Design

Prospective observational study of rectal cancers treated by colorectal multidisciplinary teams between January 2002 and October 2003.

Setting

11 colorectal units in four European countries.

Participants

408 consecutive patients presenting with all stages of rectal cancer and undergoing magnetic resonance imaging before total mesorectal excision surgery and histopathological assessment of the surgical specimen.

Main outcome measures

Accuracy of magnetic resonance imaging in predicting a curative resection based on the histological yardstick of presence or absence of tumour at the margins of the specimen.

Results

354 of the 408 patients had a clear circumferential resection margin (87%, 95% confidence interval 83% to 90%). Specificity for prediction of a clear margin by magnetic resonance imaging was 92% (327/354, 90% to 95%). High resolution scans were technically satisfactory in 93% (379/408). Surgical specimens were histopathologically graded as complete or moderate in 80% (328/408), and the median lymph node harvest was 12 (range 0-49). Magnetic resonance imaging predicted clear margins in 349 patients. At surgery 327 had clear margins (94%, 91% to 96%).

Conclusion

High resolution magnetic resonance imaging accurately predicts whether the surgical resection margins will be clear or affected by tumour. This technique can be reproduced accurately in multiple centres to predict curative resection and warns the multidisciplinary team of potential failure of surgery, thus enabling selection of patients for preoperative treatment.

SUBMITTER: MERCURY Study Group

PROVIDER: S-EPMC1602032 | biostudies-literature | 2006 Oct

REPOSITORIES: biostudies-literature

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Publications

Diagnostic accuracy of preoperative magnetic resonance imaging in predicting curative resection of rectal cancer: prospective observational study.

BMJ (Clinical research ed.) 20060919 7572

<h4>Objective</h4>To assess the accuracy of preoperative staging of rectal cancer with magnetic resonance imaging to predict surgical circumferential resection margins.<h4>Design</h4>Prospective observational study of rectal cancers treated by colorectal multidisciplinary teams between January 2002 and October 2003.<h4>Setting</h4>11 colorectal units in four European countries.<h4>Participants</h4>408 consecutive patients presenting with all stages of rectal cancer and undergoing magnetic resona ...[more]

PMID: 16984925

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Project description:BackgroundMyocardial perfusion cardiovascular magnetic resonance (CMR) is a well-established method for detection of ischemic heart disease. However, ECG gating problems can result in image degradation and non-diagnostic scans, particularly in patients with arrhythmias.MethodsA turboFLASH saturation recovery pulse sequence was used without any ECG triggering. One saturation pulse followed by 4-5 slices of undersampled radial k-space images was acquired rapidly, on the order of 40-50 msec per image. The acquisition of the set of 4-5 slices was continuously repeated approximately 4 times per second. An iterative constrained reconstruction method was used to reconstruct the ungated images. The ungated perfusion images were post-processed into three different sets of images (ungated, self-gated to near systole, and self-gated to near diastole). To test the ungated approach and compare the different processing methods, 8 patients scheduled for coronary angiography underwent stress and rest perfusion imaging with the ungated acquisition. Six patients had a history of atrial fibrillation (AF). Three blinded readers assessed image quality and presence/absence of disease.ResultsAll 8 subjects successfully completed the perfusion CMR protocol and 7/8 underwent coronary angiography. Three patients were in atrial fibrillation during CMR. Overall, the CMR images were of high quality as assessed by the three readers. There was little difference in image quality between patients in AF compared to those in sinus rhythm (3.6±0.7 vs. 3.3±0.5). Stress/rest perfusion imaging showed normal perfusion in 4 patients, fixed perfusion defects in 2 patients, and reversible perfusion defects in 2 patients, corresponding with angiographic results. Pooled results from the independent readers gave a sensitivity of 0.92 (CI 0.65-0.99) and specificity of 0.92 (CI 0.65-0.99) for the detection of coronary artery disease using ungated perfusion imaging. The same sensitivity, and a specificity of 1 (CI 0.76-1), was achieved when the images were self-gated after acquisition into near systole or near diastole.ConclusionsUngated radial dynamic perfusion CMR can give high quality imaging in patients in sinus rhythm and during atrial fibrillation. In this small cohort, high diagnostic accuracy was possible with this rapid perfusion imaging sequence. An ungated approach simplifies the acquisition and could expand the role of perfusion CMR to include patients with arrhythmia and those with gating problems.

Dataset Information

Diagnostic accuracy of preoperative magnetic resonance imaging in predicting curative resection of rectal cancer: prospective observational study.

Objective

Design

Setting

Participants

Main outcome measures

Results

Conclusion

Publications

Diagnostic accuracy of preoperative magnetic resonance imaging in predicting curative resection of rectal cancer: prospective observational study.

Similar Datasets

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