Clinical case:

The present article describes the case of a 48-year-old male patient with no history of interest referred from primary care to evaluate a left perineal tumour occasionally painful. Radiological findings reveal a fatty lesion whose suspected diagnosis is hibernoma being confirmed once the histopathological examination is made.

Relevance:

Hibernoma is frequently mistaken for lipoma or liposarcoma due to its clinical and radiological features, being crucial the differentiation to avoid potentially iatrogenic therapies.

Conclusion:

Hibernoma is a rare, slow-growing and painless benign neoplasia originated from brown fat. Although it can be suspected according to diagnostic imaging, the definitive diagnosis is histological and the treatment of choice consists of a complete resection. There are no reported cases of recurrence or metastases at the long-term follow-up.