title: Tumor architecture exerts no bias on nuclear grading in breast cancer diagnosis.
abstract: We recently reported that nuclear grading in prostate cancer is subject to a strong confirmation bias induced by the tumor architecture. We now wondered whether a similar bias governs nuclear grading in breast carcinoma. An unannounced test was performed at a pathology conference. Pathologists were asked to grade nuclei in a PowerPoint presentation. Circular high power fields of 27 invasive ductal carcinomas were shown, superimposed over low power background images of either tubule-rich or tubule-poor carcinomas. We found (a) that diagnostic reproducibility of nuclear grades was poor to moderate (weighed kappa values between 0.07 and 0.54, 27 cases, 44 graders), but (b) that nuclear grades were not affected by the tumor architecture. We speculate that the categorized grading in breast cancer, separating tubule formation, nuclear pleomorphism, and mitotic figure counts in a combined three tier score, prevents the bias that architecture exerts on nuclear grades in less well-controlled situations.
authors.affiliation: Institute of Pathology, CHUV, Lausanne, Switzerland. brauliomora@gmail.com
authors.forename: Braulio
authors.initials: B
authors.lastname: Mora
authors.forename: Dario
authors.initials: D
authors.lastname: Bombari
authors.forename: Stephan C
authors.initials: SC
authors.lastname: Schaefer
authors.forename: Marcus
authors.initials: M
authors.lastname: Schmidt
authors.forename: Jean-Francois
authors.initials: JF
authors.lastname: Delaloye
authors.forename: Fred
authors.initials: F
authors.lastname: Mast
authors.forename: Hans-Anton
authors.initials: HA
authors.lastname: Lehr
mesh_terms: D015982:Bias; D001943:Breast Neoplasms / Q000175:diagnosis / Q000453:epidemiology* / Q000473:pathology*; D018270:Carcinoma, Ductal, Breast / Q000175:diagnosis / Q000453:epidemiology* / Q000473:pathology*; D002467:Cell Nucleus / Q000473:pathology; D003071:Cognition; D003625:Data Collection; D005260:Female; D019983:Guideline Adherence; D006801:Humans; D008940:Mitotic Index; D060787:Neoplasm Grading / Q000523:psychology*; D015203:Reproducibility of Results