We spoke to Dr. Tsoumakidou to learn more about her presentation at CIRSE 2022.
Bone tumour management: Pitfalls and complications to avoid
Percutaneous interventional radiology (IR) treatments play an important role in the curative management of benign osseous tumours (i.e. osteoid osteoma, osteoblastoma, aneurysmal bone cyst) and oligometastatic bone disease. Furthermore, they can be used with a palliative intent in order to improve symptoms and decrease the risk of skeletal related events (i.e. pathologic fractures, compression of the spinal cord or nerve roots, life-threatening hypercalcemia) in patients with multiple bone metastases.
It is essential to define the therapeutic strategy, curative versus palliative, and choose the most adapted treatment modality considering the nature of the bone lesion, the patient’s prognosis, quality of life, postoperative function and risk of post-treatment complications. Curative treatment of oligometastatic disease signifies that an ablative technique is used to achieve tumour destruction. In comparison, palliative treatment of an osteolytic lesion in weight-bearing bones necessitates some type of consolidation and cement injection in order to increase the bone’s resistance to compressive stress. Ablative and consolidation techniques are associated whenever indicated.
IR procedures for the management of bone tumours have a favourable safety profile, with clinically significant complications being uncommon (2.3-5.5%) [1, 2]. Secondary fracture (1.8-5.5%) is one of the most common complications encountered after bone thermal ablation [1, 3, 4]. Lesions involving weight-bearing bones, the presence of cortical disruption, the extra-bone extension of the disease, large tumour volume and prior radiotherapy are all predisposing factors for post-ablation insufficiency fractures . According to the anatomic location of the lesion and the subjected forces (compression, tension, torsion or shear), consolidation with cement injection and/or osteosynthesis (screws, nails) should be considered to prevent post-ablation insufficiency fractures.
Although not common (<5%), neural thermal injury can arise when treating tumours in proximity to neural structures (nerves, spinal cord). Neural complications during spinal ablations occur between 1.7 and 16% [5, 6]. It is mandatory to be familiar with the cross-sectional anatomy in order to recognise the structures at risk. Treating spinal lesions can result in thermal damage of the spinal cord and spinal nerve roots. Sacral lesions are often in close distance to the sacral nerve roots and sacral plexus. Posterior acetabulum and ischial spine ablations can be complicated with sciatic nerve injury. Upper thoracic and shoulder treatments can put the brachial plexus at risk. Prolonged exposure of a neural structure to extreme temperatures (>40°C and <10°C) results in local neurolysis and interruption of electrical conduction, which can be temporary, usually resolving between 6-18 months, or permanent. Therefore, it is crucial to consistently re-examine the anatomy in order to recognise the neural structures in proximity and thus, to be able to take all necessary precautions in order to actively and passively protect the neural structures at risk. More challenging locations may require some type of thermal- (thermocouples) and/or neuro-monitoring (electrostimulation of motor nerves, somatosensory and motor evoked potentials).
Other infrequently observed complications after bone thermal ablation include: site infection, hematoma (0.5%), skin burns (2.8%) and skin frost-bite lesions, tumour seeding, avascular necrosis, arthropathy (0.9%) and pneumothorax (0.9%) . Skin burns can be produced when the bone trocar is not sufficiently retrieved; thus, the active point of the electrode is not completely exposed. Skin burns can also be produced when treating superficial lesions in proximity to the epidermis . In the second case scenario, sufficient hydro dissection of the subcutaneous fat can provide the necessary safety distance between the ablation zone and the epidermis. Cryoshock has not been reported yet after bone cryoablation.
Accessing blastic bone lesions can be challenging. In order to avoid device breakage, drills should be considered for bone penetration. Furthermore, operators need to dispose of grasping implements and be familiar with the different described practical tips  in order to be able to retrieve any retained fragments.
Cement leakage is not a rare phenomenon during cementoplasty, but in the majority of patients has no clinical manifestations. High quality real-time imaging (fluoroscopy) and careful monitoring of the spinal canal and epidural-paravertebral veins allow on-time recognition of any cement leakage.
To conclude, percutaneous bone tumour treatments are both safe and effective in the hands of experts. Several conditions need to be taken in consideration in order to identify pitfalls and diminish complications.
Figures: Please click on the images to expand
Figure 1A, 1B. Laser ablation of a juxta-cortical osteoid osteoma of the acetabulum. Hydro-dissection of the articular cavity was performed to protect the articular cartilage from thermal injury.
Figure 2. Curative cryoablation of a breast cancer metastasis on the sacrum in proximity to the sacral plexus. Thermal monitoring of the sacral plexus (thermocouple) and hydrodissection were used to avoid the neural thermal damage.
Figure 3A, 3B. Cryoablation and cemetoplasty of a right iliac metastasis. Due to the hardness of the bone, the thickness of the soft tissues and the manipulations on the bone trocart, there was breakage of the coaxial bone needle during bone penetration. The needle fragment was left in place, as it was completely intraosseous.
Figure 4A, 4B. L4 aneurysmal bone cyst treated with cryoablation. Figure 4C, 4D, 4E. Electrostimulation and CO2 dissection of the epidural space were necessary in order to avoid neural thermal injury.
University Hospital of Lausanne, Lausanne/CH
Dr. Georgia Tsoumakidou is a consultant interventional radiologist at the University Hospital of Lausanne, Switzerland. She received her medical degree from the University of Athens in 2003, a master degree in interventional radiology in 2006 and completed her radiology residency in 2010. She then performed a two-year fellowship in the University Hospital of Strasbourg in France, where she subspecialised in image guided percutaneous procedures, with a special interest in musculoskeletal interventions and MR-guided procedures. The focus of her clinical practice is oncologic interventions, both vascular and percutaneous, with particular reference to liver locoregional therapies, pain management procedures and MSK interventions. Dr. Tsoumakidou is an active member of CIRSE and serves as a reviewer for CVIR, European Radiology and Skeletal Radiology journals. She has authored and co-authored more than 60 articles in peer-review journals and is a co-author of several book chapters. During the past years, she has been awarded the Magna Cum Laude and Cum Laude prizes-distinctions in CIRSE, ECR and RSNA congresses for ten EPOS presentations.
- Autrusseau PA, et al. Safety and efficacy of percutaneous Cryoablation of extraspinal thyroid cancer bone metastases with curative intent: Single-center experience with a median follow-up of more than 5 years. JVIR 2022 https://doi.org/10.1016/j.jvir.2022.03.016
- Cazzato RL, et al. Percutaneous microwave ablation of bone tumours: a systematic review. Eur Radiol 2021; 31(5):3530-3541
- Cazzato RL, et al. Complications following percutaneous image-guided radiofrequency ablation of bone tumors: a 10-year dual-center experience. Radiology 2020;296(1):227–235
- Auloge P, et al. Complications of percutaneous bone tumor cryoablation: a 10-year experience. Radiology 2019; 291(2):521–528
- Tsoumakidou G, et al. Percutaneous image-guided laser photocoagulation of spinal osteoid osteoma: A single-institution series. Radiology 2016;278(3):936-43
- Nakatsuka A, et al. Percutaneous radiofrequency ablation of painful spinal tumors adjacent to the spinal cord with real-time monitoring of spinal canal temperature: a prospective study. Cardiovasc Intervent Radiol 2009;32:70–5).
- Parisot L, et al. CT-guided microwave ablation of osteoid osteoma: Long-term outcome in 28 patients. Diagn Interv Imaging 2022;S2211-5684(22)00073-0
- Cazzato RL, et al. Percutaneous management of accidentally retained foreign bodies during image-guided non-vascular procedures: Novel technique using a large-bore biopsy system. Cardiovasc Intervent Radiol 2016;39:1050-1056