# A Comprehensive Narrative Review of the Impact of Pelvic Radiotherapy on Pelvic Bone Health: Pathophysiology, Early Diagnosis, and Prevention Strategies

## TL;DR

Pelvic radiotherapy can weaken bones and cause fractures, especially in older patients, but new imaging and treatments may help prevent this.

## Contribution

This review provides an updated understanding of how pelvic radiotherapy affects bone health and highlights prevention strategies.

## Key findings

- Radiotherapy can cause insufficiency fractures, especially in the sacral ala of elderly patients.
- MRI is effective in detecting radiotherapy-induced fractures and differentiating them from metastases.
- Pharmacological agents like amifostine and desferrioxamine show promise in protecting bone health during radiotherapy.

## Abstract

Radiotherapy is a commonly used modality in pelvic malignancies such as prostate, gastrointestinal, or gynecological, either as a primary treatment or an adjuvant post-surgery. Despite its positive impact on the prognosis of these patients, it was found in several studies that it contributes to insufficiency fractures in different sites of the pelvis, more commonly in the sacral ala. This is particularly true for elderly patients. There are several hypotheses on how radiotherapy affects bone health, as it destroys the bone matrix and causes obliterative vasculitis. Several imaging techniques, particularly magnetic resonance imaging (MRI), help detect the radiotherapy-induced fracture and distinguish it from metastases. Some modalities, such as intensity-modulated radiotherapy (IMRT) and brachytherapy, have decreased fracture risk by escaping the adjacent structures to the targeted organ. Pharmacological interventions such as amifostine and desferrioxamine are promising in terms of bone protection, which necessitates further studies to confirm their mechanism of action.