title: Absence of epithelial atypia in B3-lesions of the breast is associated with decreased risk for malignancy.
abstract: BACKGROUND
  Lesions of uncertain malignant potential (B3) represent a heterogeneous group with an overall risk for malignancy of 9.85-35.1% after total resection. Positive predictive values (PPV) for malignancy vary depending on B3 subtype. The aim of this study was to evaluate the PPV for malignancy in B3 lesions and to determine the clinical significance of atypia-dependent sub-classification (a = without epithelial atypia; b = with epithelial atypia) of B3 into B3a and B3b and papillary lesions (PL) in PLa and PLb.
  
  
  METHODS
  219 patients with histopathologically proven B3 lesions on core needle/vacuum-assisted biopsy who subsequently underwent diagnostic excision biopsy were included in this study. PPVs for malignancy were reported for B3 in general and all B3 sub-categories. Logistic regression analysis identified associations between B3-subgroups and outcome after excision biopsy as well as the impact of clinical and diagnostic findings on excision diagnosis.
  
  
  RESULTS
  The overall PPV rate was 10.0% (22/219). Excision histology exhibited a higher malignancy rate in PLb (2/7; PPV: 28.6%) than in PLa (6/127; PPV: 4.7%) (p = 0.057) and in B3b (12/50; PPV: 24.0%) compared to B3a category (8/165; PPV: 4.8%) (p < 0.001).
  
  
  CONCLUSIONS
  These findings support the necessity of B3 lesion sub-classification into B3a and B3b and of PL into PLa and PLb when considering epithelial atypia. The determination of atypia status represents a relevant factor in risk-stratification for clinical management of B3 lesions. Should future studies using the sub-classification of PL confirm these results, observation may be a safe option for the clinical management of patients with asymptomatic PLa lesions.
authors.affiliation: Department of Obstetrics and Gynecology, Medical Center - University of Freiburg, Germany; Faculty of Medicine, University of Freiburg, Germany. Electronic address: sebastian.mayer@uniklinik-freiburg.de.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Mayer
authors.affiliation: Institute of Surgical Pathology, Department of Pathology, Medical Center - University of Freiburg, Germany; Faculty of Medicine, University of Freiburg, Germany.
authors.forename: Gian
authors.initials: G
authors.lastname: Kayser
authors.affiliation: Institute for Medical Biometry and Statistics, Medical Center - University of Freiburg, Germany; Faculty of Medicine, University of Freiburg, Germany.
authors.forename: Gerta
authors.initials: G
authors.lastname: Rücker
authors.affiliation: West London Mental Health NHS Trust, United Kingdom.
authors.forename: Diana
authors.initials: D
authors.lastname: Bögner
authors.affiliation: Department of Obstetrics and Gynecology, Medical Center - University of Freiburg, Germany; Faculty of Medicine, University of Freiburg, Germany; Institute of Veterinary Medicine, Georg-August-University Goettingen, Germany.
authors.forename: Marc
authors.initials: M
authors.lastname: Hirschfeld
authors.affiliation: Department of Obstetrics and Gynecology, Medical Center - University of Freiburg, Germany; Faculty of Medicine, University of Freiburg, Germany.
authors.forename: Christiane
authors.initials: C
authors.lastname: Hug
authors.affiliation: Department of Gynecology and Obstetrics, University Medical Center RWTH Aachen, Aachen, Germany.
authors.forename: Elmar
authors.initials: E
authors.lastname: Stickeler
authors.affiliation: Department of Obstetrics and Gynecology, Medical Center - University of Freiburg, Germany; Faculty of Medicine, University of Freiburg, Germany.
authors.forename: Gerald
authors.initials: G
authors.lastname: Gitsch
authors.affiliation: Department of Obstetrics and Gynecology, Medical Center - University of Freiburg, Germany; Faculty of Medicine, University of Freiburg, Germany.
authors.forename: Thalia
authors.initials: T
authors.lastname: Erbes
mesh_terms: D062005:Biopsy, Large-Core Needle; D001940:Breast / Q000000981:diagnostic imaging / Q000473:pathology*; D001943:Breast Neoplasms / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D018270:Carcinoma, Ductal, Breast / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D002285:Carcinoma, Intraductal, Noninfiltrating / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D004847:Epithelial Cells / Q000473:pathology*; D005260:Female; D006801:Humans; D006965:Hyperplasia / Q000473:pathology; D008327:Mammography; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D014463:Ultrasonography
keywords: Atypia; B3 lesion; Breast cancer; DCIS; Lesion of uncertain malignant potential; PPV for malignancy; Papillary lesion