ADENOCARCINOMA OF THE ILEUM MIMICS CROHN'S DISEASE – CASE REPORT

Introduction Crohn's Disease (CD) is characterized by episodes of inflammation of the gastrointestinal tract with the classic symptoms: abdominal pain, diarrhea, change in stool pattern and weight loss. These symptoms are equivalent in cases of intestinal neoplasia.

Method Study based on medical record analysis and bibliographic review with the objective of reporting the importance of the differential diagnosis of ileal adenocarcinoma in cases previously diagnosed with CD. Case report: Female patient, 45 years old, started experiencing abdominal pain in July 2022. Under investigation, she underwent colonoscopy with subsequent biopsy of fragments, but there was no assertive clarification of the diagnosis, starting empirical treatment for CD with corticosteroids associated with azathioprine (AZA). After 8 months of treatment, she presented symptoms suggestive of intestinal sub-occlusion and computed tomography (CT) of the abdomen showed significant circumferential and irregular parietal thickening of the segment of the distal ileum, associated with infiltration of the adjacent adipose tissue, in addition to luminal narrowing. Findings that favor the clinical suspicion of inflammatory bowel disease (IBD), especially CD. As her condition progressed, she underwent an ileocolectomy procedure with subsequent referral of an anatomical piece to the pathology department. During the study, the pathology identified moderately differentiated adenocarcinoma of the distal segment of the ileum, with a usual tubular/intestinal pattern, ulcer-infiltrating, ring-shaped, extending to the mesentery and free surgical margins. With satisfactory postoperative evolution, she maintained the clinical segment with chemotherapy according to protocol.

Discussion Neoplasia of the small intestine is rare with an annual incidence of 2.1 cases in 100,000. Adenocarcinoma is the second most common histological type, and its ileal location makes this entity even less common. Symptoms in patients with CD are indistinguishable from those with adenocarcinoma. Thus, this fact tends to mask and delay the diagnosis of malignancy. Around 10% of patients originally diagnosed with IBD have a change in diagnosis after reevaluation.

Conclusion The discussed finding highlights not only the heterogeneity of these diseases, but also the difficulty of correctly determining their diagnoses. In this context, systematic monitoring is, therefore, necessary so that the condition does not remain undetermined, interfering with the patients' quality of life and thus reducing their problems.

No conflict of interest has been declared by the author(s).

Publication History

Article published online:
25 April 2025