A Rare Case of Large Lateral Chest Wall Hibernoma.

Hibernomas, rare benign tumors originating from brown adipose tissue, pose diagnostic challenges due to their infrequent occurrence and slow growth. We present a case of a 38-year-old woman with a progressively enlarging mass in her right lateral chest wall, initially stable in size but growing during pregnancy and causing pain and functional impairment. Radiological evaluation, including x-ray and MRI, provided inconclusive results, necessitating a biopsy for a definitive diagnosis. Ultrasound-guided needle aspiration biopsy revealed typical histopathological features consistent with hibernoma. A subsequent total surgical excision with negative margins was performed. The patient achieved complete recovery without recurrence during two years of follow-up. This case underscores the importance of considering hibernoma in the differential diagnosis of adipose tissue tumors, particularly in atypical clinical presentations. Moreover, it highlights the challenges in diagnosing and managing hibernomas and emphasizes the role of MRI and biopsy in achieving accurate diagnosis and optimal treatment outcomes. Continued reporting of such cases is crucial for increasing awareness and improving the management of this rare tumor.