When you are using this surgical dose of radiation, its like you are throwing a small nuclear bomb into the heart of the cancer. So, your results are well translated and majority of the targets which we will be shooting down, the success rate ranges anywhere between 80 to 90%.
Shahid Akhter, editor, ETHealthworld spoke to Dr Shankar Vangipuram, HOD – Radiation oncology department, HCG Apex Cancer Centre, Mumbai to know more about the cutting edge advantages of radiosurgery and the arsenal of technologies available at HCG. Edited excerpts :
Trends in Radiosurgery
Radiation is all about delivering the treatments accurately and precisely. When I say accuracy, it is all about getting very close to the target which you are aiming to. This treatment is delivered over a period of 6 to 7 weeks, 5 days a week. In radiosurgery we are abbreviating this 6 to 7 weeks treatment to probably single session or maybe 3 or 4 sessions. So, there are several advantages and value which get unlocked once you start applying this technology in the care of the patients. There are around 22 to 25 centres across country practicing this but our area of specialisation are more into intracranial radiosurgery and functional radiosurgery, specifically more for movement disorders, epilepsy etc. So, this is where our strength essentially lies with. So, if you ask me the future of Radiation therapy, it’s all about abbreviated forms of treatment which we call as radiosurgery.
Advantages of Radiosurgery
If we are treating any patient with radiosurgery there are several advantages which come on to the table. First, it is totally non-invasive. When I say radiosurgery, you think about a surgeon who essentially cuts the skin, approaches the target, removes it and closes it. In radiosurgery, we are not cutting the skin, it is totally non-invasive. Now when you are doing it in a non-invasive way you don’t need anaesthesia. If the patient has any medical risk factors like diabetes, hypertension, cardiac failure, pulmonary emphysema or kidney failure, surgery will always carry a greater risk. So, whenever there are medical risk factors, this a much preferred treatment modality. We are not opening the skin, therefore there is no blood loss. When there is no blood loss you actually don’t need to give any blood transfusions. Then the precision and accuracy of the treatment which we are giving fall into the range of 0.3 mm and this is achieved using robotics in place. When you are using this surgical dose of radiation, its like you are throwing a small nuclear bomb into the heart of the cancer. So, your results are well translated and majority of the targets which we will be shooting down, the success rate ranges anywhere between 80 to 90%. So therefore, you have to have a thorough understanding about this entire science to deliver the results which you intend to.
Types of Application
Radiosurgery typically has two applications, the first is the Intracranial application, which is inside the brain. In the brain you can treat several conditions like arteriovenous malformation, specifically the deep seated AVMs and benign tumors. In these tumors we have to really understand that if the surgeon leaves anything behind, they have a propensity to grow back. So, the better way to manage this situation is whatever residual the surgeon has left behind is to go ahead and shoot it down. These are all the intracranial applications. Apart from these, we can also do functional radiosurgery that is used for neuralgia pain. When you say neuralgia pain it is typically the Trigeminal Neuralgia which you see where the patient suffers extreme lancinating pain in one half of the face.
Apart from this, functional radiosurgery is also practised in movement disorders like medically refractory, parkinson’s disease and epilepsy, specifically the medial temporal lobe epilepsy. So, all these are the kind of intracranial applications of radiosurgery. Now the same radiosurgery can also be applied for extracranial science, specifically more medically inoperable lung cancer, elderly 67 years smoker have decreased lung capacity, doing surgery will always carry a risk. So therefore, the better way to manage such kind of situation is to do radiosurgery which is totally non-invasive.
Similarly, you have liver cancer, the best form of treatment is to go ahead and do liver transplant but not many in India can afford it. So, as a bridge to liver transplant for those who can’t afford it and where the lesion is more than 3 cm, which is majority of the times we routinely and clinically encounter, that is the situation you can have radiosurgery of the liver. For the prostrate also, there is evidence which is coming now and a 5-year mature data. Now the data is coming where a prostrate cancer need not be treated for two months. Just one week or ten days treatment will suffice. Similarly, you can treat a pancreatic cancer which you cannot operate, borderline resectable pancreatic cancers or those locally advanced pancreatic cancers. All these can easily be treated with abbreviated forms of treatment using surgical dosage of radiation.
Role of technology and the edge at HCG
There are several technologies which are available in place. So, at HCG we have two technologies straightaway called X knife which is available in Mumbai and a Cyberknife which is also going to come in another 4 to 5 months to Mumbai. And one Cyber knife is there in our Bangalore centre. So, essentially with X knife and Cyberknife, we can do radiosurgery. The third knife what we routinely use for specifically more for the brain applications is called as Gamma knife. In Gamma knife we use typically the Cobalt sources to generate the gamma rays and that is used to target the cancers. Our Proton centre is going to come in couple of years in Delhi and should be ready for doing these high-end applications. Right now, we are practising all the radiosurgeries either on X knife or Cyber knife.