Updated 3 October 2007

Clinical Presentation

In general, small bowel adenocarcinoma presents with very non-specific symptoms, the commonest of which is crampy abdominal pain. Other complaints include: nausea/vomiting, abdominal distension or hemorrhage. In a series of 58 patients with small bowel adenocarcinoma, the following table summarizes the symptoms and signs at presentation. Diagnosis is often delayed by 8-10 months, due to the non-specific nature of patients’ symptoms and diverse locations within the small bowel affecting the effectiveness of diagnostic procedures.

* From Ito et al (2003), Talamonti et al (2002) and Dabaja et al (2004)

Imaging Studies

Plain Film Studies

These have limited use in diagnosis, but can demonstrate air-fluid levels when obstruction develops.

Contrast Studies

Although small bowel follow through (SBFT) commonly demonstrates an abnormality between 50-80% of primary malignant tumors, direct evidence of a tumor occurs in only 30-44% of cases. Enteroclysis has a greater sensitivity of 95% versus 61% for SBFT.

Computed Tomography (CT)

Contrast enhanced CT has the potential to detect extra-luminal extension, mesenteric nodal enlargement, hepatic and peritoneal metastases.

Angiography

For those tumours with a brisk rate of bleeding, contrast angiography may detect contrast extravasation or tumor-associated neovascularity within the bowel wall.

Endoscopic Procedures

Video Push Enteroscopy

The use of very long steerable endoscopes measuring up to 250 centimeters provides a greater chance of detecting abnormalities in the proximal and mid jejunum compared to conventional upper gastrointestinal endoscopy. The procedure is more difficult, requires greater time and sedation than conventional techniques.

Wireless Capsule Endoscopy

For patients with chronic gastrointestinal blood loss, undiagnosed by conventional means, the use of wireless capsule endoscopy may provide a better chance of making a diagnosis. In one series of patients with a history of chronic gastrointestinal blood loss for at least 6 months (average 29+/- 24 months), compared to video push enterostomy, wireless capsule endoscopy provided a greater diagnostic yield with 66% positive findings versus 28% with push enteroscopy. Most of the sources of bleeding were areas of angiodysplasia with few small bowel malignancies detected. Patients prefer the capsule over push enteroscopy noting less pain and absence of sedation. Technical problems have included reduced battery life, reduced optics, and inability to wash lesions for better viewing and reduced picture quality. As well, push enteroscopy can provide therapeutic access to bleeding lesions.

Laparotomy

For patients presenting with bowel obstruction, ascites or abdominal mass and no confirmed diagnosis pre-operatively, a laparotomy may be the only reasonable approach. In a Dutch series, reported in 1997, in 29 out of 99 cases (30%) the definitive diagnosis could only be made at laparotomy. A large series of patients reported from the MD Anderson Cancer Centre noted that distally located (ileum) small bowel adenocarcinoma required a laparotomy for diagnosis in 16 of 28 patients.