Treatment of Vertebral Body Metastases in Palliative Patients: Radiofrequency Ablation, a New and Secure Treatment Option

Abstract

IntroductionAbout a quarter of all people dying in germany succumb to cancer. In 40% metastases of the spine are present. Potentially vertebro- or kyphoplasty in combination with a tumorablation may be a treatmentoption in painful metastases or metastases with fractures. Cementing alone leads to dislocation of metastases and scattering of tumoral mass in the patient. (Principle of Archimedes) Therefore local reduction of tumoral mass should be performed whenever possible.The use of ablation systems in the vicinity of nervous and vascular structures is potentially dangerous. The presented observational study is to assess the security and effectivity of a new spinal intravertebral radiofrequency-ablation sonde. Materials and MethodsDuring the period from 11/2013 until 6/2015 we treated 24 patients (14f, 10m) with 58 vertebral bodies with the radiofrequency-ablation system followed by radiofrequency-kyphoplasty. The mean follow-up was 7,04 months (total 169 mon.). Mean age 67 years (Range 51–84 years). All vertebral bodies were treated unipedicular. Cancers treated were breast cancer (8), multiple myeloma (7), lung cancer (3), chondrosarcoma (1), prostate (1), urothel (1), cancer of unknown primary (1), gastric cancer (1) and fibrous dysplasia (1). In two patients this technique was combined with minimal-invasive percutaneous osteosynthesis. The ablationsystem contains a navigable, bipolar electrode with two temperature detection sondes, which allow for real-time temperaturemonitoring at the proximal end of the ablation zone. The ablation zones were planned preoperatively via computertomography and mri. Patients were examined for neurological or other deficits postopertively and during follow-up outpatient clinic visits. ResultsThe ablation of the preoperatively determined areas were intraoperatively radiologically and via monitoring of temperature securely performed. The maneuverability of the ablation device allowed via unipedicular access the exact positioning of the device in the planned ablation zone. No patient presented neurological deficits or vascular lesions due to radiofrequency-ablation. One cementextravasation, while performing kyphoplasty at a site where the lateral wall of the vertebral body had already been preoperatively destroyed by the tumor, lead to affection of a peripheral nerve with intercostal neuralgia (<7 days). ConclusionsThe treatment of 24 tumorpatients in the advanced stadium of the cancer disease with percutaneous, minimally-invasive radiofrequency-ablation followed by cementaugmentation could be verified as secure treatmentoption for vertebral body metastases. The combination of a unipedicular access for radiofrequency-ablation and –kyphoplasty facilitates the careful and safe treatment of palliative cancer patients.