Angiosarcomas of bone are rare tumors constituting 1% of all malignant bone tumors. They can be either solitary or multifocal and can easily be misinterpreted as multiple myeloma or metastasis radiologically. We present a case of multifocal angiosarcoma arrising in foot bones, the diagnosis of which was difficult clinically, radiologically and pathologically. The histologic findings observed in both bioptic and amputation specimens were provided.

The patient was a 56 years-old man who has undergone coronary by-pass and saphenous vein surgery 3 months ago. He has been suffering from pain and swelling on left foot since then. The lesion was suspicious for atypical fungal infection, metastasis or lymphoma radiologically. “Tru-cut” biopsy revealed extensive necrosis and the lesion resembled an inflammatory and reactive process at first glance. Morphologic mimickers of the lesion like lymphoma, metastasis and small round cell tumors were excluded immunohistochemically and the diagnosis of “malignant vasculary tumor” was made upon CD- 31 positivity of tumor cells, presence of erytrocytes, cells with intracytoplasmic lumina and increased mitotic activity. In amputation specimen a multifocal tumor having areas of necrosis and hemorrhages was observed involving predominantly calcaneus but also infiltrating talus, distal tibia and achilles tendon. The maximum diameter of tumor was 5 cm in calcaneus. Adjuvant chemotherapy could not be given because of cardiac problems.

The case was presented to increase awareness on this rare, diagnostically problematic issue, the classification of which is controversial.