Ultrasound diagnosis of small bowel adenocarcinoma in Crohn's disease: A case report and review of literature.

BACKGROUND

Crohn's disease (CD)-related small bowel adenocarcinoma (SBA) is a rare adenocarcinoma that is difficult to detect and diagnose in its early stages and is associated with long-standing inflammation, which may predispose patients with CD to SBA. This case report describes a patient with CD who was diagnosed with SBA using intestinal ultrasonography (IUS).

CASE SUMMARY: A 38-year-old male diagnosed with CD since 23 years of age was maintained in remission with mesalamine, although he did not take his medication regularly. The patient presented with recurrent dull abdominal pain, bloating, and a three-month history of diarrhea (3 times per day) with unformed stools. Abdominal examination revealed mildly diffuse tenderness. IUS revealed eccentric thickening (23 mm) in the terminal ileum. The hierarchical structure of the intestinal wall disappeared, revealing the "pseudo-kidney" sign. A stricture was identified in the terminal ileum with dilation of the proximal intestinal tract. Color Doppler flow imaging revealed linear blood flow. Contrast-enhanced ultrasound revealed highly heterogeneous enhancement with rapid washout in ileocecal junction, suggesting malignant transformation of CD with intestinal obstruction. Pathological examination revealed poorly differentiated adenocarcinoma of the ileocecal junction.

CONCLUSION

Active surveillance for SBA using IUS is prudent, given its advantages of real-time dynamic imaging, high-detail resolution, and low cost.