# Atypical Femoral Fracture During Long-Term Treatment With Denosumab in Patients With Metastatic Bone Tumors

## TL;DR

This paper reports a rare case of atypical femoral fracture in a patient receiving long-term denosumab treatment for metastatic bone tumors.

## Contribution

The study highlights the importance of early detection and awareness of atypical femoral fractures in patients on denosumab.

## Key findings

- A patient on long-term denosumab developed an atypical femoral fracture.
- Early consultation with an orthopedic surgeon could have prevented severe complications.
- Disseminating information on rare adverse events like AFF is crucial for patient safety.

## Abstract

Bone-modifying agents (BMAs) are used to treat metastatic bone tumors and are also administered to reduce bone loss caused by bone metastases. Adverse events, such as osteonecrosis of the jaw and hypocalcemia, have been associated with long-term use of bisphosphonates; however, atypical femoral fracture (AFF) is rare. We encountered a patient who received long-term treatment with denosumab (DEN) and had a history of zoledronic acid hydrate administration. Severe complications may have been prevented if the patient had consulted with an orthopedic surgeon when she developed pain in the left thigh one month before AFF. The provision of relevant information on AFF to patients starting treatment with DEN may lead to its early detection. Since it is important to disseminate rare adverse events to the public, we report the present results based on a literature review.