Adenocarcinoma of the duodenum

Clinical History

A 53-year-old man is being studied for abdominal pain and constitutional symptoms.

Imaging Findings

Abdominal CT post administration of oral and intravenous contrast shows circumferential wall thickening of the 3rd portion of duodenum. The lumen of the duodenum is stenosed and not obstructed. No alteration of the surrounding mesenteric fat and no signs of local invasion. [Figure 1, 2, 3, 4]

Discussion

Bowel wall thickening may be related to a number of entities, including normal variants, inflammatory conditions, and neoplastic disease. The CT findings that need to be analysed when assessing thickened bowel include pattern of attenuation; degree of thickening; symmetric versus asymmetric thickening; focal, segmental, or diffuse involvement; and associated perienteric abnormalities. [1]
Cases of neoplasm often present as asymmetric or eccentric thickening of a short segments of bowel wall with a homogeneous attenuation. [1]
Neoplasms of the small bowel are rare lesions that account for less than 5% of all gastrointestinal tumours, although the differential diagnosis for a small bowel tumour is extensive. At least one-quarter of primary small bowel malignancies are adenocarcinomas, 50% of small bowel adenocarcinomas are found in the duodenum, especially near the ampulla; in the remaining cases, the jejunum is more commonly involved than the ileum. [1, 2, 3]
Risk factors for the development of adenocarcinoma of the small bowel include a history of Crohn’s disease, Sprue, Peutz-Jeghers syndrome, Lynch syndrome II, congenital bowel duplication, ileostomy, or duodenal or jejunal bypass surgery. [3]
Small bowel adenocarcinoma may appear at CT as an annular narrowing with abrupt concentric or irregular “overhanging edges”, a discrete tumour mass, or an ulcerative lesion. Usually only a short segment of the bowel is involved. Gradual narrowing of the lumen leads to partial or complete small bowel obstruction. [3]
A large, aggressive, ulcerated adenocarcinoma can be mistaken for lymphoma; however, lymph node metastases in adenocarcinoma are usually less bulky than those in lymphoma. The lymph node chains to be assessed with CT are located in the root of the mesentery and in the pyloric, hepatic, peripancreatic, cecal, and ileocolic regions. [3]

Differential Diagnosis List

Final Diagnosis

Adenocarcinoma of the duodenum

URL:	https://www.eurorad.org/case/10338
DOI:	10.1594/EURORAD/CASE.10338
ISSN:	1563-4086