Long-Term Follow-Up of Adamantinoma of the Tibia Complicated by Metastases and a Second Unrelated Primary Cancer: A Case Report and Literature Review.

Adamantinoma is a rare, low-grade malignant tumor of the bone which grows slowly and typically occurs in the diaphysis of long bones, particularly in the tibia. Adamantinomas have the potential for local recurrence and may metastasize to the lungs, lymph nodes, or bone. We report a case of a 14-year-old female with a tibial adamantinoma who underwent wide resection with limb salvage and has subsequently been followed up for 18 years. The patient went on to have both a local soft tissue recurrence 5 years after the resection and metastases to both an inguinal lymph node and the right lower lobe of the lung 8 years after that recurrence, all of which have been treated successfully with marginal resections. Unique to this case, the patient was also incidentally found to have chromophobe-type renal cell carcinoma when undergoing a partial nephrectomy to resect a presumed metastasis of her adamantinoma. Genetic testing has not revealed any known genetic predisposition to cancer.