Radiofréquence bipolaire et cimentoplastie dans le traitement des métastases osseuses

Safety and efficacy of microwave ablation for breast cancer thoracic metastases

Background

The objective of the study was to assess the safety and efficacy of microwave ablation (MWA) for breast cancer thoracic metastasis.

Materials and methods

Twelve patients in our institution with a single lesion of breast cancer thoracic metastases received MWA and invasive spine surgery from August 2014 to November 2016. MWA was executed using the MWA system (2,450 MHz) at 40 W or 50 W with thermometers to control the ablation end points. The pathology of thoracic metastases was confirmed through intraoperative biopsy before ablation. The postoperative complications were recorded. The patients were followed up at 1, 3 and 6 months with contrast-enhanced computed tomography and magnetic resonance imaging to monitor for tumor recurrence.

Results

The average duration of follow-up for breast cancer thoracic metastases patients (mean age 52.7±8.4 years) was 10.2 months. The rate of postoperative main complications was 8.3% (1/12). The recurrence rate was 16.6% (2/12) as confirmed by persistent enhancement.

Conclusion

MWA may be used as the adjuvant treatment for thoracic metastases of breast cancer. Results showed that few significant complications and less local recurrence occurred during the follow-up stage. Future research should aim at discovering more about the time controls for microwave-tissue interaction and treatment parameters before widespread use.

Percutaneous low-pressure bone stenting to control cement deposition in extensive lytic lesions

OBJECTIVE

To evaluate low-pressure bone stenting combined with cementoplasty in extensive lytic lesions.

METHODS

A single-centre study involving four consecutive patients (four women) with extensive lytic tumours was performed. The average age was 65 years. Surgical treatment was not indicated or not wished for by the patients. Institutional review board approval and informed consent were obtained. Percutaneous consolidation was performed by an interventional radiologist under fluoroscopy guidance. Follow-up was assessed using the visual analogue scale (VAS).

RESULTS

Under general (n = 2) or local (n = 2) anaesthesia, five 11-gauge bone biopsy needles were advanced in four lesions. Five auto-expandable uncovered stents (10-14 mm diameter and 40-60 mm long) were inserted. In all cases, bone cement was successfully placed into the tumours. The volume of cement that was injected through the cannulas into the stents was 5-10 mL. Using VAS, pain decreased from more than 9/10 preoperatively to less than 2/10 after the procedure for all patients (p < 0.05). No complications occurred during the follow-up (8-19 months).

CONCLUSION

This study suggests that cementoplasty combined with low-pressure bone stenting could allow effective bone stabilization resulting in pain relief.

KEY POINTS

• Low-pressure bone stenting is possible. • This technique improves cement injection control. • The procedure allows effective bone stabilization resulting in pain relief.

Retrograde Transpubic Approach for Percutaneous Radiofrequency Ablation and Cementoplasty of Acetabular Metastasis

We report a case of painful and disabling anterior acetabular bone metastasis treated with bipolar radiofrequency ablation and cementoplasty. Due to the high risk of complications related to the proximity of the femoral neurovascular structures with a direct approach, we successfully performed a retrograde transpubic approach under combined CT and fluoroscopic guidance. In the present report, we describe this approach detailing its indications, advantages, and the technical tips to achieve a safe and satisfactory procedure.

[Radiofrequency ablation for palliation of soft tissue tumor pain]

PURPOSE

To assess the efficacy of radiofrequency (RF) ablation for palliation of soft tissue tumor pain.

MATERIALS AND METHODS

Retrospective study of 12 patients receiving palliative treatment for soft tissue tumors (5 primary tumors including 4 sarcomas and 1 PEComa and 7 metastatic tumors) with pain refractory to standard management. RF ablation was performed under CT or ultrasound guidance.

RESULTS

The efficacy was determined by using pain scores and treatment regimen modifications after RF ablation. Response was graded as absent, partial or complete. Short term symptomatic relief was observed in 100% of cases, with complete response in 43% of cases ; Mid term and long term symptomatic relief was observed in 70% and 83% of cases respectively. We also observed dosage reduction for narcotics with corresponding reduction in related side-effects and functional improvement in some patients. A single case of complication with serosanguinous collection within a region of necrosis was observed.

CONCLUSION

Radiofrequency ablation for palliation of soft tissue tumor pain may be a useful complement to standard management. It results in symptomatic improvement with few complications.

Radiofrequency energy on cortical bone and soft tissue: a pilot study

BACKGROUND

Radiofrequency-generating energy devices have been used clinically in musculoskeletal procedures to provide hemostasis and capsular shrinkage (thermal capsulorrhaphy). However, the dose-effects are not well known.

QUESTIONS/PURPOSES

We therefore determined dosage effects of radiofrequency energy on bone, skin incisions, and joint capsule in sheep.

METHODS

Five mature sheep had six 2.5-cm(2) tibial periosteal defects and six 1.0-cm skin incisions assigned to six treatments varying by watts and fluence (f = watts . seconds/cm(2)): (1) untreated control, (2) 50 W for 9.5 seconds (190f; n = 5), (3) 110 W for 4.3 seconds (190f; n = 5), (4) 170 W for 2.8 seconds (190f; n = 5), (5) 170 W for 5.6 seconds (380f; n = 5), or (6) 170 W for 8.4 seconds (570f; n = 5). Outcomes included hemostasis, contraction, healing, and histomorphometry for inflammation and necrosis at 2 weeks.

RESULTS

Radiofrequency energy application on skin at 190f or greater had more than 80% hemostasis and dose-dependent contraction, inflammation, and necrosis. Radiofrequency energy application on bone had good (70%) hemostasis at 190f and complete (> 95%) hemostasis at 380f and 570f, without histologic or clinically detectable necrosis.

CONCLUSIONS

Hemostasis can be achieved with radiofrequency energy at 190f in skin and bone. Bone necrosis was not detected at up to 570f. Using fluence greater than 190f in skin achieved dose-dependent necrosis and incisional contraction.

CLINICAL RELEVANCE

Radiofrequency energy can be used on bone and skin for hemostasis, but potential incisional complications, such as necrosis and an atypical firm and desiccated surface, should be expected.

Radiofrequency application to the growth plate in the rabbit: a new potential approach to epiphysiodesis

BACKGROUND

Radiofrequency energy is being used more and more frequently in orthopaedics, mainly in the treatment of bone tumors. We postulated that radiofrequency ablation may produce growth plate lesions similar to those observed in the bone and conducted this study to see whether radiofrequency may be used as a technique for producing epiphysiodesis.

METHODS

We randomized 60 8-week-old female New Zealand white rabbits into 3 groups. Group A was destined for a total epiphysiodesis at 60 degrees C, group B was destined for a total epiphysiodesis at 90 degrees C, and group C for a lateral hemiepiphysiodesis at 90 degrees C. Radiofrequency energy was delivered in 1 minute in all 3 groups. Using fluoroscopic imaging, radiofrequency was applied percutaneously to the left proximal tibial physis whereas the right growth plate received a sham procedure. A bicortical pin was used to evaluate the longitudinal growth rate at every monthly radiologic control, beginning 8 weeks after the procedure. Comparisons between the right and left side and between groups A and B were achieved using a paired t test. A histopathologic study was conducted in parallel to the radiographic study.

RESULTS

In a radiograph at the 8-week point, pin migration was 4.74 mm on the left side compared with 9.72 mm on the right (P<0.0001), in group A. In group B, pin migration on the left was 1.37 mm compared with 5.49 mm on the right (P<0.0001). In group C, mean angular deviation was 11.6 degrees on the left compared with 1.9 degrees on the right (P=0.0001). These differences were maintained until the end of growth. Pathology specimens revealed cellular anarchy, loss of columnar stratification, and height of the physis on the left side, which occurred earlier and were more pronounced in group B than in group A. In group C, these changes involved only the lateral half of the left physis whereas its medial counterpart remained normal. There was no evidence of articular cartilage damage.

CONCLUSIONS

This experimental study shows that radiofrequency can efficiently and rapidly achieve epiphysiodesis. It is one of many methods that can be used for this purpose. The development of new electrodes suitable for use on human growth plates and the elaboration of specific utilization protocols may lead to its use in children. Its simplicity and precision may lead to a quick and efficient growth arrest with little pain and postoperative disability in addition to reduced costs.

CLINICAL RELEVANCE

Radiofrequency has proved to be effective in producing growth arrest in rabbits with no complications. Technical improvements and adaptations may allow its use for pediatric limb inequalities or angular deformities in the near future.

Medullary thyroid cancer: management guidelines of the American Thyroid Association

BACKGROUND

Inherited and sporadic medullary thyroid cancer (MTC) is an uncommon and challenging malignancy. The American Thyroid association (ATA) chose to create specific MTC Clinical Guidelines that would bring together and update the diverse MTC literature and combine it with evidence-based medicine and the knowledge and experience of a panel of expert clinicians.

METHODS

Relevant articles were identified using a systematic PubMed search and supplemented with additional published materials. Evidence-based recommendations were created and then categorized using criteria adapted from the United States Preventive Services Task Force, Agency for Healthcare Research and Quality.

RESULTS

Clinical topics addressed in this scholarly dialog included: initial diagnosis and therapy of preclinical disease (including RET oncogene testing and the timing of prophylactic thyroidectomy), initial diagnosis and therapy of clinically apparent disease (including preoperative testing and imaging, extent of surgery, and handling of devascularized parathyroid glands), initial evaluation and treatment of postoperative patients (including the role of completion thyroidectomy), management of persistent or recurrent MTC (including the role of tumor marker doubling times, and treatment of patients with distant metastases and hormonally active metastases), long-term follow-up and management (including the frequency of follow-up and imaging), and directions for future research.

CONCLUSIONS

One hundred twenty-two evidence-based recommendations were created to assist in the clinical care of MTC patients and to share what we believe is current, rational, and optimal medical practice.

Cementoplasty in the management of painful extraspinal bone metastases: our experience

PURPOSE

The aim of this study was to demonstrate the effectiveness of interventional techniques in the palliative management of painful extraspinal bone metastases.

MATERIALS AND METHODS

Cementoplasty alone or in combination with radiofrequency (RF) ablation was performed in 14 skeletal extravertebral segments in 13 patients with ages ranging from 50 to 74 (average 67) years. The primary tumours were myeloma (n=5), renal carcinoma (n=5), hepatocellular carcinoma (n=2) and bladder carcinoma (n=2). Metastases were located at the acetabulum (n=4), femur (n=5), humerus (n=1), scapula (n=2) and iliac bone (n=2). The clinical indication was a pain intensity score >4 on the visual analogue scale (VAS) partially or totally refractory to analgesic medication. Clinical evaluation was based on clinical and neurological conditions before and immediately after the procedure and during the follow-up.

RESULTS

Technical success was achieved in all cases. Ten patients were treated by cementoplasty alone and four cases by cementoplasty combined with RF ablation. After treatment, all patients experienced improved symptoms, as demonstrated by the VAS score, which remained constant during follow-up. All patients were followed for between 2 and 14 (average 6.1) months. We had one major complication in a patient who developed an abscess, which was treated by percutaneous drainage.

CONCLUSIONS

In our experience, cementoplasty alone for small lesions or combined with RF ablation in larger lesions is an effective and safe therapy in the palliative management of painful extraspinal bone metastases.

[Image-guided ablation of bone tumors: review of current techniques]

Multiple interventional radiology techniques are available for percutaneous ablation of bone tumors: alcohol, laser, radiofrequency, microwave, ultrasound, and cryogenic ablation. Several indications have already been validated, including radiofrequency ablation of osteoid osteoma and bone metastases, with results superior to conventional treatment. More indications should be added over the coming years. The purpose of this article is to review the principles of the different ablation techniques, summarize their respective indications and results and discuss their implementation and the eventual combination with cementoplasty techniques.