The international multicenter study by Schutgens et al. in the October 7, 2020 issue of JBJS reports findings from an analysis of >300 cases of patients diagnosed with either classic adamantinomas (ADs) or osteofibrous dysplasia-like adamantinomas (OFD-ADs) who were followed for 7 to >10 years. The mean age at diagnosis was 17 years. The authors conclude that OFD-AD and AD are “parts of a disease spectrum but should be regarded as different entities.” Their findings, they say, also “support reclassification of OFD-AD into the intermediate locally aggressive [but non-metastatic] category” of bone tumors.
Perhaps the most clinically interesting findings in this study are related to local recurrence, which the authors describe as a “multifactorial” phenomenon in both tumor types. They found local recurrence in 22% of the OFD-AD cases and 24% of the AD cases. None of the recurrences in the OFD-AD group progressed to AD, which is a malignant disease with metastatic potential.
The authors found that the unadjusted cumulative incidence of local recurrence was higher if a pathological fracture was reported and if resection margins were contaminated. So, to reduce the risk of local recurrence in both tumor types, Schutgens et al. suggest “preventing pathological fracture after diagnosis and achieving uncontaminated margins with resection.” The uncontaminated resection should include the periosteum of the involved bone at the time of surgery.