What is Thermal Ablation?
Thermal ablation is a technique that employs heat or cold to destroy tumors in various parts of the body. The heat-based therapies are Microwave ablation [MWA] and Radiofrequency ablation [RFA]. cryoablation is the freezing of the cancer tissue.
How do I perform Thermal Ablation?
I perform tumor ablation using image guidance and a percutaneous approach without open surgery, although in some instances ablation is performed with laparoscopy guidance. Accurate placement of an electrode inside the tumor is essential for achieving complete tumor control.
Types of cancers with Thermal Ablation?
Cancers in almost every organ have been treated with thermal ablation. The most common organs that have been treated with thermal ablation are liver, kidney, adrenal, lung, bone, spine, prostate, and thyroid cancer.
The adverse effect of Thermal Ablation?
At microwave or radiofrequency ablation, there is a small risk of damage to nearby organs. In order to safely achieve a complete tumor burn or freeze, it may be necessary to give intravenous contrast for better identification of the tumor or it may be necessary to inject IV fluids to push away nearby structures from the ablation zone.
What is the evidence for Thermal Ablation?
One of the most studied ablative techniques is Radiofrequency ablation[ [RFA] and it has been evaluated as first-line therapy in early Hepatocellular carcinoma [HCC]. RFA has been shown to improve overall survival by 68%, with overall survival of 76% at three years.
Does tumor size affect treatment?
Large tumor size is a predictor of tumor progression and recurrence. It is more difficult to safely obtain an adequate ablation zone for larger tumors and therefore the chance of complete cure is less.
Thermal ablation vs. surgery?
There is no significant difference in survival between the thermal ablation and surgery with respect to small liver tumors less than 2cm. After surgery, the incidence of tumor recurrence is less compared to ablation. Patients treated with thermal ablation have less serious side effects and can go home on the same day of treatment.
RFA vs. microwave ablation?
In RFA, an electric current in the RF range is delivered through one or several needle electrodes and grounding pads to produce heat-based thermal cytotoxicity. It is not advisable for patients with pacemakers.
MWA uses electromagnetic energy that heats the tissue and is less prone to heat sink effect and the treatment is faster and larger burns can be achieved for larger tumors. Microwave is a newer technique than RFA.
Conclusion
Thermal ablation with radiofrequency or microwave ablation is the standard of care for patients with early-stage hepatocellular carcinoma who are not suitable for surgery. Thermal ablation comprising of Microwave or Radiofrequency or Cryoablation is very safe and effective for local control of cancer in various organs has been shown to improve survival.
