musculoskeletal and connective tissue disorders
Primary Malignant Bone Tumors
Adamantinoma
Adamantinoma is rare (< 1% of malignant bone tumors) and most often develops in the tibia. It usually occurs in adolescents and people who are in their 20s but can occur at any age. Adamantinoma is slow-growing and often manifests with pain and palpable fullness. The lesion typically manifests in the anterior crest of the tibia, and x-rays show a "soap bubble" osteolytic appearance. The histologic appearance is a biphasic pattern of epithelial and osteofibrous tissue. The lesion can be confused with osteofibrous dysplasia of the anterior tibial cortex, which is benign. Some clinicians think osteofibrous dysplasia of the anterior tibial cortex may be a precursor to adamantinoma but without the epithelial component that would then make it a cancer. Metastases do occur, primarily to the lungs, but are rare. Treatment of adamantinoma consists of wide resection and reconstruction of the defect. Occasionally, amputation is necessary. 