Hibernomas: a single-institution experience and review of literature

Hibernomas are rare benign soft tissue tumors that are included in the broad spectrum of lipomatous neoplasms. The tumors are derived of brown fat, and the clinical and imaging presentation can mimic other neoplastic conditions. We discuss a 20-year experience at a single academic institution to define the clinical presentation, imaging, and management of these rare neoplasms. A retrospective review of all cases of histologically proven hibernoma over a 20-year period was performed. Clinical presentation, demographics, radiologic reports and images, and pathology reports were all reviewed and collected. We identified 19 cases of hibernoma. The clinical presentation and radiographic characteristics are presented. Our findings also demonstrated that local recurrence of these benign soft tissue tumors was rare, and local recurrence was only documented in one of the 19 cases, which was most likely due to inadequate initial resection rather than true recurrence. Hibernomas are composed of brown fat, in which the imaging can be misleading. Once diagnosed, surgical resection is usually curative.