Former world darts champion Mark Webster has been diagnosed with a rare form of blood cancer. Webster, who claimed World Championship glory on the British Darts Organisation (BDO) circuit in 2008, has not worked at a darts event for Sky Sports since February and has this week revealed why during a wide-ranging interview on Darts World’s YouTube channel. Welsh left-hander Webster discovered in January that he had a rare form of blood cancer called hairy cell leukaemia and has not worked since he started chemotherapy in February. “It sounds bad when you say leukaemia, but…it’s got a good prognosis, 95 per cent of cases are successful. I will be put into some sort of remission at some point, but just the recovery at the minute is not going to plan in terms of the speed of it,” Webster explained. “My white blood counts are still not recovering, so therefore my immune system is not great at the minute, hence why I can’t go back to work.…