Appendicular Mucocele Associated with a Rectosigmoid Tumor Process: A Rare Case and Review of the Literature

Abstract

Appendicular mucocele is a rare lesion of the appendix characterized by the accumulation of mucus in the appendicular lumen (Caspi, et al., 2004), causing dilatation of the appendicular lumen. Its pathogenesis is controversial, and two pathophysiological theories have been developed: an obstructive theory and a neoplastic theory. The obstruction may be: an appendicular endocrine tumor, non-secretory, adenoma or adenocarcinoma of the cecum or appendix, endometriosis, extrinsic compression by nodules of peritoneal carcinosis, specific infections: stercolith, foreign bodies, appendicular volvulus or plication, appendicular diverticulum. We report the case of a 64-year-old patient with no previous surgical history (Caspi, et al., 2004), followed for a rectosigmoid tumor process, admitted in an emergency setting for neoplastic occlusion. An abdomino-pelvic CT scan showed circumferential and irregular stenosing parietal thickening of the recto-sigmoid hinge, and cystic distension of the appendix measuring 22mm in diameter, enhanced after injection of contrast medium. The patient underwent a retrograde appendectomy and an anterior colorectal resection with mechanical anterior colorectal end-to-end anastomosis. Pathological analysis confirmed the diagnosis of appendiceal mucocele (Nagpal and Malhotra, 2020) and presence of a few tumour cells within pools of mucin infiltrating the submucosa in the colorectal resection specimen. The postoperative course was straightforward (Caspi, et al., 2004), and the patient was discharged on the fifth postoperative day.