Lipoblastoma

Background/purpose: Lipoblastoma is a rare benign mesenchymal tumor of embryonal fat that occurs almost exclusively in infants and children. This study was done to determine the clinical and pathologic characteristics of lipoblastoma.

Methods: Nine cases of pathologically proven lipoblastoma from 1979 to 1997 were reviewed. There were 6 boys and 3 girls ranging in age from 3 months to 29 months.

Results: A soft tissue mass was the chief complaint in 7 patients, abdominal distension in 1 patient with a retroperitoneal mass, and defecation difficulty in 1 patient with a perirectal mass. In 4 patients, tumors occurred on the back. Other tumor location includes the neck, scrotum, retroperitoneum, perirectal area, and buttock in 1 patient each. Lesions measured 2.3 to 19.5 cm. Complete excision was done in 8 patients. One perirectal tumor was removed by both the posterior sagittal approach and the intraabdominal approach but incompletely resected. Two tumors located on the back recurred with intraspinal extension 12 months and 18 months after resection. Second resection and second resection with laminectomy were done. Leg pain and urinary incontinence developed in 1 patient but improved on conservative treatment.

Conclusions: Lipoblastoma is a benign neoplasm but can frequently recur (25%) in spite of complete excision. Lipoblastomas occurring on the back had a high recurrence rate (50%) and associated with intraspinal extension. J Pediatr Surg 36:905-907.