Researchers writing in the medical journal The Lancet have found that toddlers are 70% more likely to develop acute lymphoblastic leukaemia than they were 20 years ago.

BBC: Clues to massive leukaemia rise

However, none of the six groupings - which included acute lymphoblastic leukaemia, brain tumours and Hodgkin's disease - showed an increasing trend between levels of radiation and rate of disease.

BBC: Radon cancer fears dismissed

"Langerhans cell sarcoma is extremely rare, with only 40-50 reported cases in the literature, and only one other case of it arising from his particular type of leukaemia (acute lymphoblastic), " the spokesperson said.

BBC: Deryn Blackwell by Becky Williams