Clinical, Radiological, and Pathological Features of Intraosseous Hibernoma: A Systematic Review of Case Reports and Case Series

Intraosseous hibernoma (IOH) is a rare benign tumor composed of brown adipose tissue within the bone, frequently mimicking metastatic lesions and leading to diagnostic challenges. This systematic review aimed to consolidate and analyze all published IOH cases to improve recognition and inform management. A comprehensive literature search was conducted in PubMed, Web of Science, Scopus, Google Scholar, and the Cochrane Library from database inception to March 2025. Studies were eligible for inclusion if they reported histopathologically confirmed cases of intraosseous hibernoma (IOH) in human patients. A total of 62 cases from 30 studies were included. The mean age was 59.2 years, with a female predominance. Lesions were most frequently located in the pelvis and spine and were typically identified incidentally during cancer staging or imaging performed for unrelated indications. Imaging often revealed sclerotic patterns on computed tomography (CT), hyperintense signals on magnetic resonance imaging (MRI) T2-weighted and short tau inversion recovery (STIR) sequences, and mild to moderate uptake on 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT). Immunohistochemistry consistently showed S100 protein positivity. Most patients underwent biopsy and were managed conservatively, with no cases of malignant transformation reported. IOH is a benign entity with distinctive radiologic and immunohistochemical features that may mimic malignancy. Awareness of its presentation can reduce misdiagnosis and unnecessary interventions, supporting biopsy-based confirmation and conservative management in most cases