EDITOR,--Johanna Adami and colleagues present evidence of an association between lymphoma and skin cancer, interpreting their findings as evidence of the role of immunosuppression induced by ultraviolet light in the pathogenesis of non-Hodgkin's lymphoma and leukaemia.1 There are, however, several reasons for believing that this conclusion may not be valid. According to the authors' line of reasoning, the incidence of lymphoma in countries where people are exposed to high doses of ultraviolet radiation should …