Treatment and Management of Osteofibrous Dysplasia Like Adamantinoma - A Single Institution Experience.

Background: Osteofibrous dysplasia (OFD) is a benign lesion that affects long bones in children. Adamantinoma (ADA) is a rare malignancy. A new entity known as "differentiated" adamantinoma or OFD-like ADA (OFDLA), has emerged. We examined the clinical outcomes of patients with these conditions. Methods: A single-institution chart review of 59 patients from 1958 to 2016 was performed. Patient and treatment characteristics were compared across tumor types. Logistic regression was used to assess differences in outcomes including receipt of surgery, local recurrence, and development of metastatic disease. Results: A total of 43 patients were diagnosed with OFD, 17 were treated surgically, and there were 6 local recurrences. Out of the 9 OFDLA patients, 7 were treated surgically, and there were 4 local recurrences. All 5 patients with ADA were treated with wide excision, there was one local recurrence treated with re-excision, and one patient developed metastatic disease after treatment. The OFDLA patients were more than four times as likely to undergo surgery compared to OFD patients (OR = 4.5, 95% CI = 1.1-26.6, Conclusions: OFD and OFDLA patients can be managed conservatively, with surgical intervention reserved for those with radiographically extensive or symptomatic lesions. ADA should continue to be treated with wide local resection. Key Concepts: (1)OFD, OFDLA, and ADA exist in a spectrum of disease, and they are rare pathological entities.(2)Historically, OFDLA and ADA were treated like true malignancies, with wide resection and reconstruction. Our data suggest that OFD and OFDLA patients can be managed conservatively, with surgical intervention reserved for those with radiographically extensive or symptomatic lesions.(3)ADA is a low-grade malignant bone tumor with indications for wide resection. Level of Evidence: III, Retrospective Cohort Study.