Non-Hodgkin's lymphoma and skin cancer. Association may be iatrogenic.

EDITOR,--Johanna Adami and colleagues postulate that exposure to ultraviolet light causes immunosuppression and, thereby, non-Hodgkin's lymphoma.1 To support their hypothesis they report that patients with non-Hodgkin's lymphoma had a relative risk of 5.5 of developing squamous cell skin cancer. Conversely, patients with squamous cell skin cancer had a twofold excess risk of developing non-Hodgkin's lymphoma or the closely related chronic lymphocytic leukaemia. The relation …