MICROWAVE ABLATION
FOR ADRENAL TUMOURS AND BONE METASTASES
Beyond liver and lung, microwave ablation has important roles in two distinct settings: oligometastatic adrenal disease, where MWA replaces surgical adrenalectomy in selected patients; and painful bone metastases, where MWA combined with cement augmentation provides effective pain control and local tumour control.
analyticsAt a Glance
- check_circleAdrenal: oligometastatic disease and selected small non-functioning lesions
- check_circleBone: painful metastases with both pain relief and local tumour control
- check_circleOften combined with cement augmentation (cementoplasty) for spine lesions
- check_circleMinimally invasive option for patients who cannot tolerate surgery
Two Distinct Applications: Adrenal and Bone
This page covers two separate MWA applications that share common themes โ minimally invasive treatment for patients who are not optimal surgical candidates. The clinical scenarios differ substantially between adrenal tumours (typically systemic disease management) and bone metastases (typically symptom palliation with local control), so each requires its own discussion.
โA patient with a single adrenal metastasis from lung cancer faces a very different decision than a patient with painful spine metastases from prostate cancer. MWA serves both โ but the goals, evidence, and patient selection differ.โ
Adrenal MWA: Oligometastatic Disease Management
For patients with isolated or limited adrenal metastases from a controlled primary cancer (lung, renal, melanoma, colorectal), MWA offers local control of the adrenal disease while preserving the contralateral adrenal gland. This can extend the period of disease control and reduce systemic burden in selected oligometastatic patients.
Bone MWA: Pain Control + Local Treatment
For painful bone metastases โ particularly in the spine, pelvis, ribs, or long bones โ MWA serves dual purposes: rapid pain relief through nerve disruption, and local tumour control reducing the risk of progression. Often combined with cementoplasty for spine lesions to restore structural stability after ablation creates a cavity.
Adrenal MWA: When and Why
The adrenal gland is a common site of metastases โ particularly from lung, breast, kidney, and melanoma primaries. For selected patients with limited adrenal disease, MWA provides an alternative to surgical adrenalectomy.
Oligometastatic Adrenal Disease (Primary Indication)
Patients with a controlled primary cancer and isolated or limited adrenal metastases (typically 1โ2 lesions, each <4 cm) where local control of the adrenal disease may meaningfully improve outcomes. Particularly relevant in lung cancer with isolated adrenal metastasis, where complete local treatment of all disease sites has shown survival benefit in selected patients.
Patients Not Optimal for Surgical Adrenalectomy
Patients with significant cardiac disease, COPD, prior abdominal surgery making access difficult, or other comorbidities that elevate surgical risk. MWA offers similar local disease control with substantially lower procedural risk.
Selected Non-Functioning Adrenal Masses
Indeterminate adrenal lesions in patients who require treatment but who are not optimal surgical candidates. Biopsy guidance and careful patient selection are essential. Functioning adrenal tumours (pheochromocytoma, aldosteronoma, cortisol-producing adenomas) typically require surgical management with specific hormonal preparation.
Salvage After Prior Adrenalectomy
Patients who previously had adrenalectomy on one side and develop new metastases in the contralateral gland. Removing the second adrenal would require lifelong steroid replacement. MWA can destroy the new lesion while preserving adrenal function โ important for patients' long-term quality of life.
Bone MWA: Painful Metastases and Structural Stabilisation
Bone metastases affect a large proportion of patients with advanced cancer โ particularly from breast, prostate, lung, and renal primaries. Pain from bone metastases can be severe and disabling. MWA has become an important option for selected painful lesions, often combined with cementoplasty for structural support.
Painful Lesions Resistant to Radiation
External beam radiotherapy is the standard first-line treatment for painful bone metastases, providing pain relief in 60โ80% of patients. For lesions that fail radiation, or where radiation cannot be repeated, MWA offers an effective second-line option. Pain relief is typically rapid โ many patients notice substantial improvement within days.
MWA + Cementoplasty for Vertebral Lesions
For painful vertebral metastases (particularly thoracic or lumbar spine), MWA ablates the tumour and creates a cavity, which is then filled with polymethylmethacrylate (PMMA) bone cement. This combination โ sometimes called "ablation + cementoplasty" โ provides immediate pain relief, prevents pathological fracture, and treats the underlying tumour. Procedure typically performed in a single session.
Long Bone and Pelvic Metastases
Painful metastases in the pelvis, femur, humerus, ribs, or other accessible bones can be treated with MWA. The procedure provides pain relief without requiring open surgery. For long bone lesions at risk of pathological fracture, MWA is often combined with prophylactic surgical stabilisation rather than cementoplasty alone.
Oligometastatic Bone Disease (Curative-Intent)
For patients with limited bone metastases (1โ3 lesions) from a controlled primary cancer โ particularly oligometastatic prostate, breast, or renal cell carcinoma โ MWA may contribute to curative-intent local treatment of all known disease sites. This is an evolving area where MWA combines with systemic therapy and other local treatments.
Patient Selection for Adrenal and Bone MWA
Selection criteria differ between adrenal and bone indications.
| Indication | Strong Candidate Profile | Less Strong / Alternative Approaches |
|---|---|---|
| Adrenal Oligometastatic Disease | 1โ2 adrenal lesions <4 cm; controlled primary; ECOG 0โ2; preserved contralateral adrenal | Bilateral adrenal disease; widespread metastatic disease beyond adrenal |
| Painful Vertebral Metastasis | Localised pain; lesion accessible; spinal cord not directly involved; structural concern | Spinal cord compression โ typically need urgent surgery or radiation |
| Pelvic Bone Metastasis | Painful localised lesion; not requiring orthopaedic stabilisation | Periacetabular lesion at high fracture risk โ may need orthopaedic surgery |
| Long Bone Metastasis | Pain with low fracture risk; or combined with surgical stabilisation | High fracture risk requiring intramedullary nailing โ typically primarily orthopaedic management |
| Adrenal Functioning Tumour | Generally NOT recommended for primary functioning tumours | Pheochromocytoma, aldosteronoma โ typically surgical with specialised preparation |
| Spinal Cord Compression | NOT appropriate for emergent treatment of cord compression | Emergency surgical decompression or urgent radiotherapy needed |
| Diffuse Multifocal Bone Disease | Selected painful focal lesions can be treated | Widespread painful bone disease โ radiation, radiopharmaceuticals, or systemic therapy preferred |
The MWA + Cementoplasty Procedure for Spine Metastases
The combined procedure for painful vertebral metastases โ sometimes the most impactful single intervention in advanced cancer pain management.
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Step 1: Pre-Procedure Evaluation
MRI assesses tumour location, spinal cord proximity, and adjacent structures. CT confirms bone architecture and vertebral integrity. Pain assessment establishes baseline. Discussion of expectations โ pain relief is typically the primary goal, though tumour control is also achieved.
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Step 2: Sedation and Prone Positioning
Patient lies prone (face down) for spinal access. Conscious sedation or general anaesthesia depending on patient preference and centre protocol. Continuous monitoring of vital signs.
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Step 3: Transpedicular Access Under Fluoroscopy or CT
Access to the vertebral body through the pedicle (the bony bridge connecting the vertebral body to the posterior elements). Bilateral pedicle access provides better tumour coverage. Position confirmed continuously with imaging.
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Step 4: Microwave Ablation
MWA antenna advanced into the tumour through the pedicle access. Energy delivered for 3โ5 minutes per ablation, often with multiple antenna positions to ensure tumour coverage while protecting nearby nerves and spinal cord.
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Step 5: Cement Augmentation (Cementoplasty)
Polymethylmethacrylate (PMMA) bone cement is injected into the ablation cavity through the same access. The cement hardens within minutes, providing immediate structural support and stabilising the vertebra. Filling is monitored with continuous fluoroscopy to prevent cement leakage.
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Step 6: Post-Procedure Recovery
Brief observation 2โ4 hours post-procedure. Most patients notice substantial pain reduction within hours. Discharged same-day or after overnight observation. Activity gradually resumed; full benefits typically apparent within 1โ2 weeks.
Outcomes Data
Published outcomes from MWA series in adrenal and bone applications.
Adrenal Oligometastasis โ Local Disease Control
Local control rates at 2 years for adrenal metastases treated with MWA.
- Lesions <3 cm80โ90%
- Lesions 3โ4 cm65โ80%
- Lesions >4 cm50โ70%
Bone Metastasis Pain Relief at 1 Month
Proportion of patients reporting meaningful pain reduction (โฅ30% on numeric rating scale) after MWA.
- Complete or Substantial Relief70โ85%
- Moderate Relief10โ20%
- No Significant Relief5โ15%
Vertebroplasty + MWA โ Structural Outcomes
Outcomes of combined MWA + cementoplasty for vertebral metastases.
- Pain Relief at 1 Month80โ90%
- Vertebral Height Preservation75โ85%
- Cement Leakage (Asymptomatic)20โ35%
- Cement Leakage (Symptomatic)<3%
Related Treatments & Resources
Explore the full microwave ablation knowledge base.
- What Is Microwave Ablation? A Patient Introduction
- Microwave Ablation for Liver Cancer (HCC): Evidence and Outcomes
- Microwave Ablation for Lung Cancer: NSCLC and Pulmonary Metastases
- Microwave Ablation for Kidney Cancer (RCC)
- Multi-Antenna MWA: Treating Large Tumours Simultaneously
- Microwave Ablation โ Full Treatment Page
Frequently Asked Questions
Common questions about MWA for adrenal tumours and bone metastases.
About Adrenal MWA
Can MWA replace surgery for adrenal cancer?
For adrenal metastases, MWA is a valid alternative to surgical adrenalectomy in selected patients. For primary adrenal cancers (adrenocortical carcinoma), surgical resection remains the standard with no established role for primary ablation. For functioning adrenal tumours like pheochromocytoma, the hormonal effects require specific surgical preparation and ablation is not typically appropriate.
Will MWA affect my adrenal hormone production?
For unilateral adrenal MWA preserving the contralateral gland, hormonal function is typically maintained โ the remaining adrenal compensates. For bilateral disease or sequential bilateral procedures, lifelong steroid replacement would be needed, similar to bilateral adrenalectomy. CancerFax's endocrine review addresses this in pre-procedure counselling.
Is there a risk of hypertensive crisis during adrenal MWA?
Yes, a small risk exists particularly with functioning adrenal tumours that may release catecholamines during ablation. This is why functioning tumours are generally not appropriate for MWA. Even for non-functioning adrenal metastases, blood pressure is monitored continuously, and alpha-blockade preparation may be used in selected high-risk patients. Experienced centres manage this risk routinely.
About Bone MWA
Will MWA cure my bone metastases?
In most settings, MWA for bone metastases is palliative โ focused on pain control and local disease management rather than cure. For selected oligometastatic patients with limited bone-only disease, MWA combined with systemic therapy may contribute to long-term disease control or even cure in highly selected cases. Discuss realistic goals with your oncology team.
Why is cementoplasty added to spine MWA?
MWA destroys tumour and creates a cavity in the vertebra, but does not restore bone strength. Adding bone cement (PMMA) immediately stabilises the vertebra, preventing collapse and pathological fracture. The combination provides both pain relief (from ablation) and structural support (from cement). The two procedures are typically performed in a single session through the same access.
How long does pain relief last after bone MWA?
Pain relief is typically rapid โ many patients notice improvement within days. Duration depends on disease biology. For oligometastatic patients with good systemic disease control, pain relief can last months to years. For patients with progressive systemic disease, pain may recur as nearby lesions grow or new lesions develop. Repeat MWA or other interventions can address new pain sites.
How does CancerFax help with adrenal or bone MWA access?
CancerFax reviews your imaging and clinical history to identify appropriate centres offering these specialised procedures. Bone MWA with cementoplasty in particular requires interventional oncology expertise that is not universally available. We coordinate centre review, provide cost estimates, and arrange travel and treatment logistics for international patients.
How CancerFax Helps
CancerFax is a specialist cancer access and patient-navigation platform. We help patients and families understand their options, organise medical records, coordinate hospital communication, and support cross-border treatment planning where appropriate.
We help collect and organise reports, scans, pathology, biomarker results, and treatment history for structured case review.
We communicate with hospitals or trial teams to assess whether a case may be suitable for further screening.
We support appointment coordination, document submission, translation, and direct communication with international departments.
For international patients, we help with practical coordination โ travel planning, hospital admission guidance, and local support.
If this option is not suitable, we help explore other relevant treatments, clinical trials, or advanced care pathways.
From inquiry through to follow-up, our coordinators provide a single point of contact for the family.
CancerFax does not guarantee treatment access, eligibility, or clinical outcome. Our role is to help patients access accurate information, structured review, and appropriate specialist pathways.
Considering MWA for Adrenal or Bone Disease?
Upload your medical records โ imaging, biopsy results if available, pain assessment, and your overall disease history. Our interventional and musculoskeletal oncology team will review your case to assess MWA candidacy and identify appropriate centres.
This content is for informational purposes only. Adrenal and bone metastasis treatment decisions require multi-disciplinary evaluation including oncology, interventional radiology, and where appropriate orthopaedic surgery and endocrinology.