Laparoscopic Excision of a Preperitoneal Incidentaloma

BACKGROUND: Dermoid cysts are rare well-differentiated benign tumors derived from ectodermal cell origins. Usually caught incidentally, they have the potential for mass effect, malignant degeneration, and rupture. Dermoid cysts can often present a unique surgical challenge. CASE REPORT: A 69-year-old male brought to the emergency department after a motor-vehicle accident had a preperitoneal incidental mass discovered on imaging. The patient was asymptomatic from the mass, though it was expanding in size. He was advised to have the mass removed, because of the possibility of malignant degeneration and rupture, and he was taken for laparoscopic surgical excision of the mass. DISCUSSION: Dermoid cysts develop from embryonic migration of ectodermal tissue to aberrant locations or implantation of epidermal tissue. Dermoid cysts in the abdominal cavity are rare, and only case reports exist characterizing these tumors. Rupture can result in a chemical granuloma when localized and can cause peritonitis when the rupture is throughout the entire abdomen. Rare reports of malignant degeneration are also reported in the literature. Surgical excision is the standard of care minimizing risk of rupture with removal.