Mucocele of appendiceal stump--an atypical presentation and a diagnostic dilemma

Appendiceal mucocele is a well-recognised entity that can present in a variety of clinical syndromes or can occur as an incidental surgical finding. The term mucocele is inherently imprecise and inclusive of both benign and malignant lesions. Mucocele of the appendiceal stump is a rare entity.

We present a case of an appendiceal stump mucocele caused by a mucinous cystadenoma clinically presented as a giant retroperitoneal mass. Diagnosis was made postoperatively, after pathological study of the surgical sample.

The case of a 54-year-old woman, with a previous appendectomy, suffering from a painful mass in the right lower quadrant of the abdomen, is reported. Imaging showed a large cystic structure at the base of the caecum. Surgery revealed a 13 x 5.5 cm retroperitoneal cystic mass, which was excised together with the appendiceal remnant. Pathological diagnosis was that of a mucocele arising from the appendiceal stump due to the development of a benign mucinous cystadenoma. The patient was discharged on the fourth post-operative day after an uneventful recovery.

Mucocele of the appendiceal stump is a rare entity. In spite of extensive pre-operative investigations, preoperative diagnosis may still remain elusive and may only be made at the time of surgery.