Small Bowel Cancer in Crohnʼs Disease: A Case Series and Review of Literature

Abstract

Purpose: To increase awareness of the potential for malignant transformation in the small bowel of patients with Crohn's disease (CD), a rare but an existential complication. We briefly describe four patients with small bowel adenocarcinoma (SBA). Methods: Clinical features of CD patients who were found to have SBA and were under our care between 2006 and 2009 were tabulated. We reviewed entries discussing “Crohn Disease” and “small bowel cancer” on MEDLINE using MeSH terms “Crohn Disease” and “Carcinoma”, focusing on the last 10 years. Results: In our patients, as summarized in the table, half were female and were diagnosed with SBA on surgical pathology. The two male patients presented with a small bowel obstruction (SBO) leading to surgery. The two women presented with pain that led to further investigations (one by colonoscopy and the other by a barium study) that led to surgical intervention revealing the diagnosis. The two patients who had obstruction had invasive disease with very poor prognosis. The two patients without invasive disease are currently doing well at 1 year and 2 years post-operation without evidence of recurrence. The literature review revealed a cumulative incidence of SBA in CD is 0.2% at 10 years and 2.2% at 20 years, being almost as high as the well-established incidence of colorectal carcinoma in Crohn's colitis. Diagnosis is often delayed, as SBA symptoms mimic active or obstructive CD. Most common SBA site is ileum. Prognosis is poor, with a 5-year survival of 20-30%.Table: Summary of patientsConclusion: CD has become a well-recognized risk factor for SBA. Our cases reflect the potential of malignant transformation in CD, especially in the setting of a small bowel stricture. The clinical presentation observed in our cases is similar to that described in published literature. A high index of suspicion is required in CD patients with strictures who fail to respond to medical management. We should be suspicious of this rare diagnosis when CD with patients fail to respond to medical management. Other imaging modalities such as PET/CT, CT enterography, capsule endoscopy, double balloon enteroscopy may aid in the preoperative diagnosis of these lesions.