A rare case of Amyand's hernia presenting as an appendicular mucocele, extending into retroperitoneum: a case report.

Background: Amyand's hernia, an uncommon occurrence, involves the incarnation of the appendix within a hernial sac, typically presenting as an inguinal hernia. The incidence of appendicular mucocele is around 0.2-0.7%. The presented case is unique, with an extensive appendicular mucocele reaching into the retroperitoneum and involving the psoas muscle. Case Description: This is a case of a 74-year-old male who presented with a 15-year history of intermittent pain in right groin, which had gradually intensified over the past 3 months. The case presentation delves into the surgical management of an extensive appendicular mucocele, with a part of it protruding as an inguinal hernia and the other portion extending retroperitoneally up to the level of the psoas muscle. A computed tomography (CT) scan identified two different tubular cystic formations in continuity with each other: one adjacent to the right psoas muscle and the other emanating from the base of the cecum in the right iliac fossa. The patient underwent surgery involving the complete dissection and excision of the lesion, followed by a mesh hernioplasty. Conclusions: The patient recovered well without any postoperative complications. An extensive literature review suggests that this is the only case that exhibits such an atypical presentation of appendicular mucocele with extensive involvement extending into the retroperitoneum and psoas muscle. Recent surgical advances and timely imaging have played a crucial role in the diagnosis and management of this case.