"When you turn on the bathroom light your reflection stares numbly back at you, gormless and vacant. You blink. Your eyes are yellow, as is your skin. You've lost weight: your pyjamas hang off your arms like the wilting leaves of a dying plant. You stare at yourself in the mirror for several surreal minutes. The thing before you is not you. But it is." In January 2011, aged 21, Tom Preston was diagnosed with stage 4 advanced aggressive...