Predictive factors for malignancy in undiagnosed isolated small bowel strictures

Background/Aims Patients with small bowel strictures have varied etiologies, including malignancy. Little data are available on the demographic profiles and etiologies of small bowel strictures in patients who undergo surgery because of intestinal obstruction but do not have a definitive pre-operative diagnosis. Methods Retrospective data were analyzed for all patients operated between January 2000 and October 2014 for small bowel strictures without mass lesions and a definite diagnosis after imaging and endoscopic examinations. Demographic parameters, imaging, endoscopic, and histological data were extracted from the medical records. Univariate and multivariate analyses were conducted to identify factors that could differentiate between intestinal tuberculosis (ITB) and Crohn's disease (CD) and between malignant and benign strictures. Results Of the 7,425 reviewed medical records, 89 met the inclusion criteria. The most common site of strictures was the proximal small intestine (41.5%). The most common histological diagnoses in patients with small bowel strictures were ITB (26.9%), CD (23.5%), non-specific strictures (20.2%), malignancy (15.5%), ischemia (10.1%), and other complications (3.4%). Patients with malignant strictures were older than patients with benign etiologies (47.6±15.9 years vs. 37.4±16.4 years, P=0.03) and age >50 years had a specificity for malignant etiology of 80%. Only 7.1% of the patients with malignant strictures had more than 1 stricture and 64% had proximally located strictures. Diarrhea was the only factor that predicted the diagnosis of CD 6.5 (95% confidence interval, 1.10-38.25; P=0.038) compared with the diagnosis of ITB. Conclusions Malignancy was the cause of small bowel strictures in approximately 16% patients, especially among older patients with a single stricture in the proximal location. Empirical therapy should be avoided and the threshold for surgical resection is low in these patients.