Closed loop large bowel obstruction due to appendiceal signet cell carcinoma.

Signet cell carcinoma of the appendix is the rarest and the most aggressive subtype of appendiceal malignancy, typically presenting with non-specific symptoms. We describe a case of a 62-year-old male with large bowel obstruction, with computed tomography demonstrating dilated large bowels from caecum to proximal sigmoid colon and pneumoperitoneum. Intraoperatively, closed loop obstruction caused by dense adherence of sigmoid colon to caecum was noted, which had resulted in caecal perforation.