title: Breast cancer in systemic lupus erythematosus.
abstract: OBJECTIVE
  Evidence points to a decreased breast cancer risk in systemic lupus erythematosus (SLE). We analyzed data from a large multisite SLE cohort, linked to cancer registries.
  
  
  METHODS
  Information on age, SLE duration, cancer date, and histology was available. We analyzed information on histological type and performed multivariate logistic regression analyses of histological types according to age, SLE duration, and calendar year.
  
  
  RESULTS
  We studied 180 breast cancers in the SLE cohort. Of the 155 cases with histology information, 11 were referred to simply as 'carcinoma not otherwise specified'. In the remaining 144 breast cancers, the most common histological type was ductal carcinoma (n = 95; 66%) followed by lobular adenocarcinoma (n = 11; 8%), 15 cancers were of mixed histology, and the remaining ones were special types. In our regression analyses, the independent risk factors for lobular versus ductal carcinoma was age [odds ratio (OR) 1.07, 95% confidence interval (CI) 1.01-1.14] and for the 'special' subtypes it was age (OR 1.06, 95% CI 1.01-1.10) and SLE duration (OR 1.05, 95% CI 1.00-1.11).
  
  
  CONCLUSIONS
  Generally, up to 80% of breast cancers are ductal carcinomas. Though our results are not definitive, in the breast cancers that occur in SLE, there may be a slight decrease in the ductal histological type. In our analyses, age and SLE duration were independent predictors of histological status.
authors.affiliation: Division of Clinical Epidemiology, McGill University Health Centre, Montreal, Que., Canada.
authors.forename: B
authors.initials: B
authors.lastname: Tessier Cloutier
authors.forename: A E
authors.initials: AE
authors.lastname: Clarke
authors.forename: R
authors.initials: R
authors.lastname: Ramsey-Goldman
authors.forename: Y
authors.initials: Y
authors.lastname: Wang
authors.forename: W
authors.initials: W
authors.lastname: Foulkes
authors.forename: C
authors.initials: C
authors.lastname: Gordon
authors.forename: J E
authors.initials: JE
authors.lastname: Hansen
authors.forename: E
authors.initials: E
authors.lastname: Yelin
authors.forename: M B
authors.initials: MB
authors.lastname: Urowitz
authors.forename: D
authors.initials: D
authors.lastname: Gladman
authors.forename: P R
authors.initials: PR
authors.lastname: Fortin
authors.forename: D J
authors.initials: DJ
authors.lastname: Wallace
authors.forename: M
authors.initials: M
authors.lastname: Petri
authors.forename: S
authors.initials: S
authors.lastname: Manzi
authors.forename: E M
authors.initials: EM
authors.lastname: Ginzler
authors.forename: J
authors.initials: J
authors.lastname: Labrecque
authors.forename: S
authors.initials: S
authors.lastname: Edworthy
authors.forename: M A
authors.initials: MA
authors.lastname: Dooley
authors.forename: J L
authors.initials: JL
authors.lastname: Senécal
authors.forename: C A
authors.initials: CA
authors.lastname: Peschken
authors.forename: S C
authors.initials: SC
authors.lastname: Bae
authors.forename: D
authors.initials: D
authors.lastname: Isenberg
authors.forename: A
authors.initials: A
authors.lastname: Rahman
authors.forename: G
authors.initials: G
authors.lastname: Ruiz-Irastorza
authors.forename: J G
authors.initials: JG
authors.lastname: Hanly
authors.forename: S
authors.initials: S
authors.lastname: Jacobsen
authors.forename: O
authors.initials: O
authors.lastname: Nived
authors.forename: T
authors.initials: T
authors.lastname: Witte
authors.forename: L A
authors.initials: LA
authors.lastname: Criswell
authors.forename: S G
authors.initials: SG
authors.lastname: Barr
authors.forename: L
authors.initials: L
authors.lastname: Dreyer
authors.forename: G
authors.initials: G
authors.lastname: Sturfelt
authors.forename: S
authors.initials: S
authors.lastname: Bernatsky
mesh_terms: D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000209:etiology* / Q000473:pathology; D018270:Carcinoma, Ductal, Breast / Q000209:etiology* / Q000473:pathology; D018275:Carcinoma, Lobular / Q000209:etiology* / Q000473:pathology; D015331:Cohort Studies; D004198:Disease Susceptibility / Q000209:etiology / Q000473:pathology; D005260:Female; D006801:Humans; D016015:Logistic Models; D008180:Lupus Erythematosus, Systemic / Q000150:complications*; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D012307:Risk Factors