Small-Bowel Neoplasms: Prospective Evaluation of MR Enteroclysis

Abstract

To prospectively evaluate the accuracy of magnetic resonance (MR) enteroclysis in the detection of small-bowel neoplasms in symptomatic patients, with conventional endoscopy, tissue specimen, capsule endoscopy, conventional enteroclysis, and follow-up findings as reference standards. The study protocol was approved by the human research committee, and all patients gave written informed consent. One hundred fifty patients (83 male, 67 female; mean age, 42.6 years; age range, 17-84 years) who were clinically suspected of having small-bowel neoplasm and whose previous upper and lower gastrointestinal endoscopy findings were normal underwent MR enteroclysis. The MR enteroclysis findings were prospectively evaluated for the presence of focal bowel wall thickening, small-bowel masses, and small-bowel stenosis. Positive MR enteroclysis findings were compared with histopathologic examination results obtained after surgical (n = 19) or endoscopic (n = 2) procedures. Negative MR enteroclysis results were compared with the results of enteroscopy (n = 5), capsule endoscopy (n = 53), or conventional enteroclysis with subsequent clinical follow-up (n = 71). The diagnostic performance of MR enteroclysis was analyzed on a per-patient basis. MR enteroclysis was successfully completed in all 150 patients and enabled correct detection of 19 small-bowel neoplasms, which were confirmed at histopathologic examination: three carcinoid neoplasms, two adenocarcinomas, two stromal tumors, five lymphomas, one angiomatous mass, three small-bowel metastases, one leiomyoma, one adenoma, and one lipoma. Overall sensitivity, specificity, and accuracy in identifying patients with small-bowel lesions were 86% (19 of 22), 98% (126 of 128), and 97% (145 of 150), respectively. Two MR enteroclysis examinations yielded false-positive findings, and three yielded false-negative findings. MR enteroclysis is an accurate modality for detecting small-bowel neoplasms in symptomatic patients.