Doctors said my excruciating back pain was down to a slipped disc - but the truth was much worse: Agony of gym-loving father, 46, diagnosed with blood cancer which could come back at any point

David Windle, 46, a deputy headteacher from Camberwell in London dismissed his back pain as a gym injury and doctors thought it was a slipped disc. But aged 44, he was diagnosed with myeloma.