Available online 8 August 2022

Fibrous dysplasia of the bone is associated with significant pain at lesion sites

Bisphosphonates have been used for pain management without clear benefits

Denosumab may decrease bone turnover and improve pain in fibrous dysplasia

More studies are needed to assess long-term effects of denosumab use

In fibrous dysplasia (FD) of the bone, a gain of function mutation in the G-nucleotide binding protein alpha subunit results in constitutively active cyclic adenosine monophosphate. Downstream effects include formation of disorganized cortex and bone marrow fibrosis. Patients with FD experience bone pain and are at risk for fracture. Bisphosphonates are traditionally used to manage pain with mixed results. We sought to report denosumab use in patients with FD at our institution and summarized the existing literature on denosumab use in FD.

We retrospectively identified patients with FD who were treated with denosumab at our institution, describing patient characteristics and outcomes. We reviewed the existing literature on denosumab use in patients with FD.

Patient 1 was diagnosed with FD at age 17 and took bisphosphonates with initial improvement in pain. Pain eventually worsened so she received 4 doses of denosumab. Patient 2 was diagnosed with FD after a fall and was treated with bisphosphonates, reporting some initial improvement in bone pain. A few years later the pain recurred, and he received 3 doses of denosumab. Both patients tolerated denosumab well but experienced no improvement in pain.

On literature review, while some serious side effects were noted, patients experienced a decline in bone turnover markers and most reported improvement in bone pain with denosumab.

Denosumab is a promising therapy for managing symptoms of FD. Further studies are needed to determine the optimal dose and duration of treatment. Its long-term effect on FD lesions is still unclear.

Fibrous dysplasia of the bone

bisphosphonate

denosumab

© 2022 Published by Elsevier Inc. on behalf of the AACE.