Perineal lipoblastoma: a case report and review of literature.

Lipoblastoma is a rare benign mesenchymal tumor that composes of embryonal white fat tissue and typically occurs in infants or young children under 3 years of age. It usually affects the extremities, trunk, head, and neck. The perineum is a rare location with only 7 cases reported in the literature. We describe a case of 3-year-old girl with a lipoblastoma arising from perineum. An approximately 4.5 cm × 3.5 cm × 2.5 cm nodule was resected in left perineum with satisfied results. Pathological examination showed that it was composed of small lobules of mature and immature fat cells, separated by fibrous septa containing small dilated blood vessels. The left perineal lipoblastoma, although rare, should be differentiated from some other mesenchymal tumors with similar histologic and cytological features.