A precise determination of the indication and careful preparation are needed for RFA.
In preparation for the procedure, we evaluate the case history and any diagnostic results already available, such as CT images, MRI scans and, if available, PET-CT scans (positron emission computed tomography). To this end, we request that a detailed medical history is provided, with a list of the treatments already applied, an indication of the progression of the disease, and the most up-to-date diagnostic images available.
Based on the documents supplied, we can check whether the most important requirements for RFA are fulfilled. If this is the case, the patient will be invited for a further consultation and work-up at our outpatient clinic for minimally invasive tumour therapy.
The procedure is generally very well tolerated under local anaesthetic and a strong pain killer so that in most cases a general anaesthetic is not needed.
During RFA, an approximately 3 mm thick needle electrode is inserted through the skin under CT guidance into the inside of the tumour. Activating the needle electrode cases the tumour area inside the target organ to heat up (to around 100°C). This kills the tumour (coagulation necrosis) (Figure 1). The ablation procedure takes around 15 to 30 minutes.
After this, the needle electrode is removed and the incision channel is sealed with special tissue glue.
Figure 1: Principle of radio-frequency ablation (RFA): By introducing high-frequency alternating current (400 – 500 kHz), the charged particles close to the applicator inserted into the tumour start to move very rapidly. This movement generates heat in the surrounding tissue and therefore leads to cell destruction.
Generally speaking, a single RFA treatment is sufficient for small tumours. Larger tumours (> 5 cm) are not treated with RFA at our facility. Instead we use brachytherapy for this situation. If the development of new lung tumours is picked up at later follow-up, the procedure can be carried out again if necessary.