An unusual diagnosis of paravertebral lesions: mediastinal myelolipoma.

BACKGROUND

Mediastinal myelolipoma is extremely rare. It is a benign nonfunctioning tumor composed of hematopoietic tissue and mature fatty tissue. Although computed tomography and magnetic resonance imaging are effective in diagnosing mediastinal myelolipoma, a definitive diagnosis is difficult to establish for rare extra-adrenal myelolipomas by imaging alone. Such tumors are often misdiagnosed as malignant retropleural liposarcoma, denoting a poor prognosis. We herein describe a 72-year-old man with multiple bilateral paravertebral mediastinal myelolipomas and discuss the imaging findings and differential diagnoses. We used a computed tomography-guided core biopsy to attain a preoperative diagnosis. Using this technique, we avoided an unnecessary surgical procedure for the patient's asymptomatic and relatively small lesions.

CONCLUSIONS

Instead of biopsy by lesion excision, we advocate conducting a precisely targeted, minimally invasive computed tomography-guided core biopsy to obtain a definitive preoperative diagnosis and thus avoid unnecessary surgery for mediastinal myelolipoma, a benign nonfunctioning tumor.