Scalp metastasis from malignant fibrous histiocytoma of bone.

Malignant fibrous histiocytoma (MFH) of bone is a relatively rare primary malignant neoplasm and an aggressive tumor, characterized by a high frequency of local recurrence and distant metastasis. The most common metastatic site is the lung (>80%), followed by bone and regional lymph node. Metastasis to other sites is extremely rare. In this report, we describe the skin as being the initial metastatic site for MFH of bone. A 42-year-old female presented with a bone tumor involving the right proximal tibia. She underwent tumor excision and knee joint reconstruction. Histologic examination confirmed a striform-pleomorphic type of MFH of bone. Six months postoperatively, the patient developed a scalp metastasis. Wide local excision was performed. Six months after the scalp operation, the patient was alive with no further relapse. We should keep the skin in mind as the possible initial site of metastatic MFH of bone.