Is history of squamous-cell skin cancer a marker of poor prognosis in patients with cancer?
GROUND: Nonmelanoma skin cancer is associated with increased occurrence of subsequent cancer and death from cancer, but it is not known whether a history of skin cancer is associated with poor prognosis after a second diagnosis of cancer. OBJECTIVE: To determine whether history of squamous-cell skin cancer is a marker of poor prognosis in patients with cancer. DESIGN: Population-based cohort study. SETTING: Sweden, 1958 to 1996. PATIENTS: All patients in the Swedish Cancer Registry with or without a first diagnosis of squamous-cell skin cancer and a subsequent or first diagnosis of non-Hodgkin lymphoma (including chronic lymphocytic leukemia) or cancer of the colon, breast, prostate, or lung. MEASUREMENTS: Relative risk (RR) for death determined by using Cox proportional hazards regression analysis. RESULTS: Patients with a history of squamous-cell skin cancer had a significantly greater risk for death than those with no such history after receiving a diagnosis of non-Hodgkin lymphoma