A breast cancer might turn out to have a close resemblance to a gastric cancer. And this kind of reorganization of cancer in terms of its internal genetic anatomy has really changed the way we treat and approach cancer in general.

Cancer has enormous diversity and behaves differently: it's highly mutable, the evolutionary principles are very complicated and often its capacity to be constantly mystifying comes as a big challenge.

In the laboratory, we call this the six-degrees-of-separation-from-cancer rule: you can ask any biological question, no matter how seemingly distant-what makes the heart fail, or why worms age, or even how birds learn songs-and you will end up, in fewer than six genetic steps, connecting with a proto-oncogene or tumor suppressor.

I left Delhi in 1989 and remember very little of how life used to be then. Increasingly, in my recent visits to Delhi, I've started to realize that the city has become intellectually very lively. It makes me want to discover the city over and over again.

Cancer was not disorganized chromosomal chaos. It was organized chromosomal chaos

It was Disney World fused with Cancerland.

When you immerse yourself in medicine you realise that hope is not absolute. It's not that simple.