title: Sirolimus use and risk of cutaneous squamous cell carcinoma (SCC) in solid organ transplant recipients (SOTRs).
abstract: BACKGROUND
  Little is known about the use of sirolimus for primary prevention of cutaneous squamous cell carcinoma (SCC) among solid organ transplant recipients (SOTRs).
  
  
  OBJECTIVE
  We examined the association between sirolimus exposure and incident SCC risk among SOTRs within Kaiser Permanente Northern California.
  
  
  METHODS
  Using a retrospective cohort of all Kaiser Permanente Northern California members given a diagnosis of SOTR from 2000 through 2010, we evaluated incident posttransplantation SCC risk in relation to sirolimus exposure. Sirolimus use was determined from electronic pharmacy records, and incident posttransplantation SCCs were identified from health plan electronic pathology records. We used extended Cox regression to examine the independent association between receipt of sirolimus and risk of SCC.
  
  
  RESULTS
  Among 3539 SOTRs, 488 were exposed to sirolimus and 47 developed an incident SCC. SCC risk was not associated with ever use of sirolimus (adjusted hazard ratio 1.18, 95% confidence interval 0.84-1.16) or cumulative duration of sirolimus exposure (adjusted hazard ratio 2.75, 95% confidence interval 0.84-9.04, comparing long-term users with nonusers).
  
  
  CONCLUSIONS
  No information was available for some known SCC risk factors, such as skin type and sun exposure.
  
  
  CONCLUSIONS
  Among a large cohort of SOTRs, sirolimus exposure was not associated with a reduction in incident posttransplantation SCC risk.
authors.affiliation: Division of Research, Kaiser Permanente Northern California, Oakland, California; Department of Dermatology, University of California at San Francisco, San Francisco, California. Electronic address: maryam.m.asgari@kp.org.
authors.forename: Maryam M
authors.initials: MM
authors.lastname: Asgari
authors.affiliation: Department of Dermatology, University of California at San Francisco, San Francisco, California.
authors.forename: Sarah T
authors.initials: ST
authors.lastname: Arron
authors.affiliation: Division of Research, Kaiser Permanente Northern California, Oakland, California.
authors.forename: E Margaret
authors.initials: EM
authors.lastname: Warton
authors.affiliation: Division of Research, Kaiser Permanente Northern California, Oakland, California.
authors.forename: Charles P
authors.initials: CP
authors.lastname: Quesenberry
authors.affiliation: Department of Heart Transplant, Kaiser Permanente Northern California, Santa Clara, California.
authors.forename: Dana
authors.initials: D
authors.lastname: Weisshaar
mesh_terms: D000328:Adult; D000368:Aged; D002294:Carcinoma, Squamous Cell / Q000453:epidemiology* / Q000209:etiology / Q000503:physiopathology; D015331:Cohort Studies; D016001:Confidence Intervals; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007166:Immunosuppressive Agents / Q000008:administration & dosage*; D015994:Incidence; D008297:Male; D008875:Middle Aged; D016377:Organ Transplantation / Q000009:adverse effects* / Q000379:methods; D016016:Proportional Hazards Models; D012016:Reference Values; D012189:Retrospective Studies; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D020123:Sirolimus / Q000008:administration & dosage*; D012878:Skin Neoplasms / Q000453:epidemiology* / Q000209:etiology / Q000503:physiopathology; D066027:Transplant Recipients / Q000706:statistics & numerical data*; D016896:Treatment Outcome
chemical_list: D007166:Immunosuppressive Agents; D020123:Sirolimus
keywords: immunosuppression; nonmelanoma skin cancer; pharmacoepidemiology; sirolimus; solid organ transplantation; squamous cell carcinoma