Lymphangitic spread from the appendiceal adenocarcinoma to the ileocecal valve, mimicking Crohn's disease.

Due to the anatomical peculiarity of the appendix, diagnosis of tumors arising from this area can be challenging by clinicoradiologic means. We report a case of a rare primary appendiceal signet ring carcinoma with an uncommon presentation. An 86-year-old woman was admitted to our hospital with subacute epigastric pain. Computed tomography demonstrated bowel wall thickening with fat stranding in the ileocecal region. The leading diagnostic consideration was inflammatory bowel disease. Upon colonoscopy, a swollen, distorted ileocecal valve was identified. The remaining colon was otherwise unremarkable. Extensive biopsy sampling of the ileocecal region and colon was performed. A lymphangitic signet ring carcinoma within the ileocecal region was diagnosed on biopsy; there was no dysplasia or carcinoma of the remaining biopsies. By cytomorphology and immunoprofile, a lymphangitic signet ring carcinoma of appendiceal origin was the primary consideration, further confirmed upon subsequent laparotomy. This case represents an unusual pattern of appendiceal tumor spread with localized, lymphangitic involvement, creating a milieu which closely simulates Crohn's disease on imaging modalities.