Percutaneous image-guided ablation of bone and soft tissue tumours: a review of available techniques and protective measures.
BACKGROUND
Primary or metastatic osseous and soft tissue lesions can be treated by ablation techniques.


METHODS
These techniques are classified into chemical ablation (including ethanol or acetic acid injection) and thermal ablation (including laser, radiofrequency, microwave, cryoablation, radiofrequency ionisation and MR-guided HIFU). Ablation can be performed either alone or in combination with surgical or other percutaneous techniques.


RESULTS
In most cases, ablation provides curative treatment for benign lesions and malignant lesions up to 3 cm. Furthermore, it can be a palliative treatment providing pain reduction and local control of the disease, diminishing the tumour burden and mass effect on organs. Ablation may result in bone weakening; therefore, whenever stabilisation is undermined, bone augmentation should follow ablation depending on the lesion size and location.


CONCLUSIONS
Thermal ablation of bone and soft tissues demonstrates high success and relatively low complication rates. However, the most common complication is the iatrogenic thermal damage of surrounding sensitive structures. Nervous structures are very sensitive to extremely high and low temperatures with resultant transient or permanent neurological damage. Thermal damage can cause normal bone osteonecrosis in the lesion's periphery, surrounding muscular atrophy and scarring, and skin burns. Successful thermal ablation requires a sufficient ablation volume and thermal protection of the surrounding vulnerable structures.


CONCLUSIONS
• Percutaneous ablations constitute a safe and efficacious therapy for treatment of osteoid osteoma. • Ablation techniques can treat painful malignant MSK lesions and provide local tumour control. • Thermal ablation of bone and soft tissues demonstrates high success and low complication rates. • Nerves, cartilage and skin are sensitive to extremely high and low temperatures. • Successful thermal ablation occasionally requires thermal protection of the surrounding structures.
2nd Department of Radiology, University General Hospital "ATTIKON", 1 Rimini str, 12462, Athens, Greece, dfilippiadis@yahoo.gr.
Dimitrios K
DK
Filippiadis
Sean
S
Tutton
Argyro
A
Mazioti
Alexis
A
Kelekis