Microwave ablation has added advantages in treating tumours

Dr. (Col) Arvind K. Chaturvedi, Director, Prof. of Radiology, Head of Radiology & imaging, RGCI, Delhi, talks to PG Times about the newer methods that have been introduced to kill tumours without surgery.

1. Beside surgery, what are the options for treating liver tumour?

The liver tumours can be either primary which means they are developing within the liver itself or they can be secondary meaning cancer is somewhere else but most of them spread at some point of time.

Surgery has been one of the options to treat these tumours as there are emerging options that can destroy the liver tumour by various methods; one method is transarterial chemoembolization where you do a vascular circulation and make the catheter tip reach right up to the tumour and inject chemotherapy, which gets blocked there and destroys the tumour. In this there are no side effects of chemotherapy like hair loss or general symptoms.

Another every emerging method to destroy liver tumours is radiofrequency ablation and it also works when the surgery has been done once and can't be done for the second time but the tumour has reoccurred.

2. How do you see the Microwave Ablation evolving?

Radiofrequency ablation is a time tested and proven method of destroying tumours but there is a new technology that has come in now which is Microwave ablation. Microwave technology has worked in different spheres like in cooking food, in communication etc.

In medical use, in order to generate the microwave you have a machine which is the microwave generator and at the same time it is similar to an electrode where you insert a needle tip into the tumour under the CT or ultrasound guidance. Once the tip of the needle is inside the tumour you connect it to the machine and start it. The tip emits microwaves which cause oscillation of water molecules which in itself causes heat generation and that heat again destroys the tumour.

So in many ways the technology is slightly different from RA fabrillation but its uses are similar and have some advantages as well.

3. How do you protect and prevent nearby structures?

The aim is to destroy only the tumour and not any adjacent normal structure which is close to it. Radiofrequency ablation and Microwave both destroy only areas of the tissue but it may happen that the area of cancer is very close to the kidney.

In such cases, one method is that we inject a fluid which is not a conductor like dextrose or glucose water into the interphase between the kidney and the liver to move the kidney away. With this technique the heat doesn't travel to the adjacent structure to destroy it and this is a time-tested thing to protect structures.

4. Is it a stand-alone treatment or will it be combined with others?

Its a great idea to combine radiofrequency ablation or microwave ablation with other techniques as the results are better and there is a synergistic effect. So if there is a breast cancer which has gone to the liver and you want destroy the tumour with radiofrequency ablation its always a good idea to give chemotherapy also.

Similarly it can be primary liver cancers which are born within the liver and have become beyond the capability of RA for microwave ablation, in that case we can do transarterial chemoembolization followed up with RA fibrillation after it has shrunk and has become amenable to radiofrequency ablation. There is also a radiotherapy tactic which is called Stereotactic Radiation Therapy.

So all these strategies are evolving but its a given fact that if you combine strategies and work together as a team the results are far better.