•Shekhar Gupta: Hello and welcome to walk the talk. I am Shekhar Gupta in Delhi's Apollo hospital's radio therapy department and my guest this week … well let me tell you this if the fight against cancer is one of the biggest challenges in medicine my guest this week invented the latest weapon in that fight.

Professor John Adler of Stanford University, welcome to walk the talk.

John Adler: Thank you Shekhar. Its very nice to meet you. I hope I can walk the talk.

•Shekhar Gupta: Well you have done in your business. You are the inventor of cyber knife which I believe is not a knife.

John Adler: No, well it's a metaphorical knife. And I mean the point is that modern technology has allowed us to get every bit more precise and every bit more aggressive and I think it is now crossed a threshold where we can really achieve a surgical like outcome and that's why we call it a knife.

•Shekhar Gupta: But its actually something that directs radiation in a very precise manner as if it was a very fine tipped knife.

John Adler: Exactly. I mean the radiation is the pauses so accurately and from so many different angles you can concentrate the radiation in a way that was never possible before. And I kind of liken it to a magnifying glass. You take the sun's energy is not so strong by itself but if you take all the sun's energy and converge it to a common point you can really kinda burn something and start a fire and in this case we start a fire and kill a tumor.

... contd.