Lipoblastoma-Related Volvulus in a Nine-Year-Old Female

Lipoblastomas are benign neoplasms that arise from embryonal adipocytes. They predominantly impact the pediatric population, with most cases occurring in the first few years of life. These tumors typically present as a soft, palpable, painless mass and tend to involve the mesenchymal tissues of the extremities and trunk. Intraabdominal involvement and intraabdominal complications secondary to lipoblastoma are incredibly rare. Here, we present the case of a nine-year-old female who presented to the emergency department (ED) with one week of intermittent lower abdominal pain. The CT abdomen/pelvis demonstrated a well-circumscribed hypodense omental mass measuring 10.1 cm x 4.7 cm x 13.4 cm with minimal mass effect or bowel displacement. At that time, the patient's abdomen was soft without tenderness, distention, or rigidity. Her initial laboratory studies and vital signs were within normal limits. She was evaluated by pediatric surgery, who, given her clinical stability, planned for an anticipated elective resection. Thirteen days after her initial ED visit, the patient returned to the ED with nausea, vomiting, and diffuse abdominal pain. Repeat CT abdomen/pelvis revealed shifting of the omental mass from the left hemi-abdomen to the right hemi-abdomen with associated mesenteric 'swirl sign' and dilated loops of small bowel consistent with small bowel obstruction. Given the patient's CT findings and signs of peritonitis on a physical exam, she was emergently taken to the operating room, where the mass along with 20 cm of small bowel intimately associated with the mass was resected. The proximal end of the involved bowel was found to be twisted and necrotic, consistent with volvulus. A specimen was sent for cytogenetics and found to be positive for FLAG1, ultimately revealing a diagnosis of lipoblastoma. The majority of lipoblastoma development is underpinned by gene rearrangements in the zinc-finger transcription factor PLAG1. Although benign, these tumors can exhibit rapid proliferation and have high recurrence rates. Patients should be monitored long-term with ultrasound (US) or MRI following surgery to assess for recurrence.