Continued growth of locally aggressive fibrous dysplasia of 22 years duration after reaching adulthood: a case report.

Fibrous dysplasia generally stops growing when patients reach adulthood. Locally aggressive fibrous dysplasia is an extremely rare subtype of fibrous dysplasia that is characterized by progressive enlargement after bone maturation, cortical bone destruction and soft tissue invasion but without malignant transformation. At 50 years of age, a tumor was found in the rib of a patient. The tumor gradually enlarged over time and imaging findings suggested a malignant tumor. The case was further complicated by restrictive lung disorder. Biopsies from multiple sites showed no malignant findings, and marginal resection with partial curettage was performed. The final diagnosis was locally aggressive fibrous dysplasia, and the restrictive lung disorder improved postoperatively. The natural history of the disease is also unknown. This is the first report in the literature to describe a case in which a lesion exhibited long-term growth over a period of 22 years after reaching adulthood.