Lipoblastoma: a rare pediatric tumor

Abstract

Since the first description in 1926 of a rare tumor of immature fat cells with exclusive presentation in pediatric patients, 200 cases have been described in the literature. 60 - 80% of lipoblastomas appear before 3 years of age, with slight predilection for males. These tumors are called lipoblastomas and have 2 clinical presentations, the circumscribed subcutaneous tumors in the extremities (70%) and the infiltrative and diffuse tumors in deep locations named lipoblastomatosis (30%). The microscopic characteristic is the presence of lipoblasts, separated by septums and surrounded by a thin vascular net. Other ancillary exams are not helpful for the diagnosis. The microscopic exam cannot differentiate lipoblastoma from other malignant tumors such as liposarcoma. Cytogenetics can be helpful for the differentiation, showing alterations in the 8th chromosome (8q 11-13) with rearrangement of PLAG1 gene. The treatment is surgical, with a relapse rate up to 33%; therefore a 2 to 5 year follow up is recommended. Other treatments are not efficacious.