title: A simple model to assess the probability of invasion in ductal carcinoma in situ of the breast diagnosed by needle biopsy.
abstract: OBJECTIVE
  The aim of the study was to develop a clinical prediction model for assessing the probability of having invasive cancer in the definitive surgical resection specimen in patients with biopsy diagnosis of ductal carcinoma in situ (DCIS) of the breast, to facilitate decision making regarding axillary surgery.
  
  
  METHODS
  In 349 women with DCIS, predictors of invasion in the definitive resection specimen were identified. A model to predict the probability of invasion was developed and subsequently simplified to divide patients into two risk categories. The model's performance was validated on another patient population.
  
  
  RESULTS
  Multivariate logistic regression revealed four independent predictors of invasion: (i) suspicious (micro)invasion in the biopsy specimen; (ii) visibility of the lesion on ultrasonography; (iii) size of the lesion on mammography>30 mm; (iv) clinical palpability of the lesion. The actual frequency of invasion in the high-risk patient group in the test and validation population was 52.6% and 48.3%, respectively; in the low-risk group it was 16.8% and 7.1%, respectively.
  
  
  CONCLUSIONS
  The model proved to have good performance. In patients with a low probability of invasion, an axillary procedure can be omitted without a substantial risk of additional surgery.
authors.affiliation: Department of Surgical Oncology, Masaryk Memorial Cancer Institute, Zluty kopec 7, 656 53 Brno, Czech Republic ; Department of Comprehensive Cancer Care, Masaryk Memorial Cancer Institute, Zluty kopec 7, 656 53 Brno, Czech Republic.
authors.forename: Oldřich
authors.initials: O
authors.lastname: Coufal
authors.affiliation: Department of Mathematics and Statistics of the Faculty of Science, Masaryk University, Kotlarska 267/2, 611 37 Brno, Czech Republic.
authors.forename: Iveta
authors.identifier: 0000-0003-3713-3504
authors.initials: I
authors.lastname: Selingerová
authors.affiliation: Department of Surgical Oncology, Masaryk Memorial Cancer Institute, Zluty kopec 7, 656 53 Brno, Czech Republic.
authors.forename: Pavlína
authors.identifier: 0000-0001-9917-1608
authors.initials: P
authors.lastname: Vrtělová
authors.affiliation: Department of Surgical Oncology, Masaryk Memorial Cancer Institute, Zluty kopec 7, 656 53 Brno, Czech Republic.
authors.forename: Petr
authors.initials: P
authors.lastname: Krsička
authors.affiliation: Department of Surgical Oncology, Masaryk Memorial Cancer Institute, Zluty kopec 7, 656 53 Brno, Czech Republic.
authors.forename: Lucie
authors.initials: L
authors.lastname: Gabrielová
authors.affiliation: Department of Pathology, Masaryk Memorial Cancer Institute, Zluty kopec 7, 656 53 Brno, Czech Republic.
authors.forename: Pavel
authors.initials: P
authors.lastname: Fabian
authors.affiliation: Department of Radiology, Masaryk Memorial Cancer Institute, Zluty kopec 7, 656 53 Brno, Czech Republic.
authors.forename: Kateřina
authors.identifier: 0000-0001-8045-4122
authors.initials: K
authors.lastname: Stískalová
authors.affiliation: Department of Radiology, Masaryk Memorial Cancer Institute, Zluty kopec 7, 656 53 Brno, Czech Republic.
authors.forename: Monika
authors.initials: M
authors.lastname: Schneiderová
authors.affiliation: Department of Comprehensive Cancer Care, Masaryk Memorial Cancer Institute, Zluty kopec 7, 656 53 Brno, Czech Republic.
authors.forename: Alexandr
authors.identifier: 0000-0003-4698-9195
authors.initials: A
authors.lastname: Poprach
authors.affiliation: Department of Surgical Oncology, Masaryk Memorial Cancer Institute, Zluty kopec 7, 656 53 Brno, Czech Republic.
authors.forename: Ivan
authors.initials: I
authors.lastname: Justan
mesh_terms: D001707:Biopsy, Needle / Q000009:adverse effects* / Q000706:statistics & numerical data*; D001943:Breast Neoplasms / Q000453:epidemiology / Q000473:pathology*; D002285:Carcinoma, Intraductal, Noninfiltrating / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000473:pathology*; D005260:Female; D006801:Humans; D015233:Models, Statistical; D012306:Risk; D014463:Ultrasonography