title: Reproducibility of a diagnosis of invasive lobular carcinoma.
abstract: OBJECTIVE
  THE fact that invasive lobular carcinoma (ILC) is often multicentric has led to mastectomies being regularly performed for this disease in some settings. Reproducibility of the histological typing of breast cancer was investigated.
  
  
  METHODS
  Fifty slides from breast cancers were assessed individually by 10 pathologists from different institutions, whose findings were compared.
  
  
  RESULTS
  The extent of matching of the reported histological types between the various pairs of pathologists ranged between 28 and 88%. Agreement was better for pathologists with special experience in breast pathology. The kappa values for the exact histological type, for pure ILC and for the presence of an ILC component, were 0.23, 0.31, and 0.32, respectively (0.64, 0.43, and 0.46 for pathologists experienced in breast pathology).
  
  
  CONCLUSIONS
  The study demonstrates that there are equivocally interpreted tumors and the presence of ILC in the histological report should not serve as the sole determinant for the performance of mastectomy.
authors.affiliation: Department of Pathology, Bács-Kiskun County Teaching Hospital, Kecskemét, Hungary. cserni@freemail.c3.hu
authors.forename: G
authors.initials: G
authors.lastname: Cserni
mesh_terms: D001943:Breast Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D018270:Carcinoma, Ductal, Breast / Q000473:pathology; D018275:Carcinoma, Lobular / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D005260:Female; D006801:Humans; D008408:Mastectomy; D015337:Multicenter Studies as Topic; D015203:Reproducibility of Results; D013223:Statistics as Topic