A rare presentation of low-grade appendiceal mucinous neoplasm within an amyand's hernia: a case report

Abstract

An Amyand's hernia is characterised as the presence of the appendix in an inguinal hernial sac. During laparoscopic cholecystectomy for gallbladder polyps, an incidental Amyand's hernia was discovered in a 75-year-old female patient. On examination, the hernia contained an appendiceal mucocele but no evidence of perforation. An open appendicectomy with tension-free mesh repair was performed for the hernia. The histopathological report of the appendix was a low-grade appendiceal mucinous neoplasm (LAMN), an entity that is just as rare as an Amyand's hernia. The patient had the right inguinal swelling for over 10 years but it was thought to be an inguinal intramuscular cyst as reported on a previous abdominal ultrasound. Mucocele of the appendix may have a benign or malignant appendiceal progress, leading to individualised diagnosis and treatment. We review an Amyand's hernia with LAMN and discuss the asymptomatic tendency yet malignant potential of appendiceal mucoceles along with treatment strategies.

Keywords: Appendix; Case reports; Hernia; Mucocele; Neoplasms.

Fig. 1.

Ultrasonography of the abdomen revealing a right inguinal cystic lesion containing echogenic layering within.

Fig. 2.

Intraoperative image of the appendiceal mucocele within the hernia.

Fig. 3.

The appendix is lined by columnar epithelium with apical mucin and elongated, hyperchromatic, pseudostratified nuclei with inconspicuous nucleoli, associated with attenuation of the muscularis propria (H&E, × 10).

Fig. 4.

Dissecting mucin. Extensive mucosal ulceration replaced by acellular mucin, dense lymphoplasmacytic infiltration, and foreign body-type multinucleated giant cells (H&E, × 10).