A 28-year-old woman presented with a complaint of a painless abdominal mass that had been increasing in size during the past few years. Several different physicians had evaluated the patient previously without a definitive diagnosis or treatment. Her only significant medical history was a routine cesarean section 4 years earlier. Physical examination findings revealed a firm, mobile, nontender, midline abdominal mass. A computed tomographic (CT) scan was performed, which showed a well-circumscribed, 10-cm mass (Figure 1). The patient was scheduled for elective exploratory laparotomy and resection.