title: Is history of squamous-cell skin cancer a marker of poor prognosis in patients with cancer?
abstract: BACKGROUND
  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.
  
  
  METHODS
  Population-based cohort study.
  
  
  METHODS
  Sweden, 1958 to 1996.
  
  
  METHODS
  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.
  
  
  METHODS
  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 (RR, 1.33), colon cancer (RR, 1.24), breast cancer (RR, 1.19), or prostate cancer (RR, 1.17). Patients with lung cancer and a history of squamous-cell skin cancer who survived for 1 year after diagnosis of lung cancer also had an increased risk for death (RR, 1.29).
  
  
  CONCLUSIONS
  Patients with a registered history of squamous-cell skin cancer have a poor prognosis after diagnosis of subsequent cancer and warrant careful medical attention.
authors.affiliation: Karolinska Institute, Stockholm, Sweden. Johan.Askling@mep.ki.se
authors.forename: J
authors.initials: J
authors.lastname: Askling
authors.forename: P
authors.initials: P
authors.lastname: Sørensen
authors.forename: A
authors.initials: A
authors.lastname: Ekbom
authors.forename: M
authors.initials: M
authors.lastname: Frisch
authors.forename: M
authors.initials: M
authors.lastname: Melbye
authors.forename: B
authors.initials: B
authors.lastname: Glimelius
authors.forename: H
authors.initials: H
authors.lastname: Hjalgrim
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001943:Breast Neoplasms / Q000401:mortality; D002294:Carcinoma, Squamous Cell; D003110:Colonic Neoplasms / Q000401:mortality; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000401:mortality; D008228:Lymphoma, Non-Hodgkin / Q000401:mortality; D008297:Male; D008875:Middle Aged; D009026:Mortality; D016609:Neoplasms, Second Primary / Q000401:mortality; D011379:Prognosis; D016016:Proportional Hazards Models; D011471:Prostatic Neoplasms / Q000401:mortality; D012044:Regression Analysis; D012307:Risk Factors; D012878:Skin Neoplasms