I began wondering, can one really write a biography of an illness? But I found myself thinking of cancer as this character that has lived for 4,000 years, and I wanted to know what was its birth, what is its mind, its personality, its psyche?

In 2005, a man diagnosed with multiple myeloma asked me if he would be alive to watch his daughter graduate from high school in a few months. In 2009, bound to a wheelchair, he watched his daughter graduate from college. The wheelchair had nothing to do with his cancer. The man had fallen down while coaching his youngest son's baseball team.

There is a duality in recognising what an incredible disease it is - in terms of its origin, that it emerges out of a normal cell. It's a reminder of what a wonderful thing a normal cell is. In a very cold, scientific sense, I think a cancer cell is a kind of biological marvel.

All cancers are alike but they are alike in a unique way.

This was yet another colonial fascination: to create the conditions of misery in a population, then subject it to social or medical experimentation.

If there's a seminal discovery in oncology in the last 20 years, it's that idea that cancer genes are often mutated versions of normal genes.

Good physicians are rarely dispassionate. They agonize and self-doubt over patients.