title: Fibroepithelial breast lesions diagnosed by core needle biopsy demonstrate a moderate rate of upstaging to phyllodes tumors.
abstract: BACKGROUND
  Fibroepithelial lesions of the breast (FEL) are atypical lesions diagnosed on core-needle biopsy. The purpose of this study was to determine the rate at which FELs are upstaged to phyllodes tumor on excision, and to examine the clinical and radiological factors that may be predictive of upstaging.
  
  
  METHODS
  A retrospective review from the medical records of patients diagnosed with FEL on CNB at a single institution between 2010 and 2015 was performed. Patients diagnosed with benign or borderline phyllodes tumors were compared to those diagnosed with fibroadenoma.
  
  
  RESULTS
  Of 74 patients diagnosed with FEL, 48 underwent excision (64.9%). Of the 48 lesions excised, pathology revealed 30 fibroadenomas (62.5%), 14 benign phyllodes tumors (29.2%), and 4 borderline phyllodes tumor (8.3%). No malignant phyllodes tumors were identified. On preoperative ultrasound, heterogeneous echotexture (p = 0.03) and lack of internal vascularity (p = 0.03) were significantly associated with upstaging to phyllodes tumor.
  
  
  CONCLUSIONS
  Surgical excision of FELs yield a pathological diagnosis of benign and borderline phyllodes tumor in 37.5% of cases. A high BIRADs score (≥4b), heterogeneous echotexture and lack of internal vascularity on ultrasound may help predict upstaging to phyllodes tumor.
authors.affiliation: Department of Surgery, McGill University Health Centre, Montreal, QC, Canada; Cedars Breast Clinic, McGill University Health Centre, Montreal, QC, Canada. Electronic address: gabriel.marcil@mail.mcgill.ca.
authors.forename: Gabriel
authors.initials: G
authors.lastname: Marcil
authors.affiliation: Department of Surgery, McGill University Health Centre, Montreal, QC, Canada; Cedars Breast Clinic, McGill University Health Centre, Montreal, QC, Canada.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Wong
authors.affiliation: Department of Surgery, McGill University Health Centre, Montreal, QC, Canada; Cedars Breast Clinic, McGill University Health Centre, Montreal, QC, Canada.
authors.forename: Nora
authors.initials: N
authors.lastname: Trabulsi
authors.affiliation: Department of Surgery, McGill University Health Centre, Montreal, QC, Canada; Cedars Breast Clinic, McGill University Health Centre, Montreal, QC, Canada.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Allard-Coutu
authors.affiliation: Department of Surgery, McGill University Health Centre, Montreal, QC, Canada; Cedars Breast Clinic, McGill University Health Centre, Montreal, QC, Canada.
authors.forename: Armen
authors.initials: A
authors.lastname: Parsyan
authors.affiliation: Cedars Breast Clinic, McGill University Health Centre, Montreal, QC, Canada; Department of Pathology, McGill University Health Centre, Montreal, QC, Canada.
authors.forename: Atilla
authors.initials: A
authors.lastname: Omeroglu
authors.affiliation: Department of Pathology, McGill University Health Centre, Montreal, QC, Canada.
authors.forename: Gulbeyaz
authors.initials: G
authors.lastname: Atinel
authors.affiliation: Cedars Breast Clinic, McGill University Health Centre, Montreal, QC, Canada; Department of Radiology, McGill University Health Centre, Montreal, QC, Canada.
authors.forename: Benoit
authors.initials: B
authors.lastname: Mesurolle
authors.affiliation: Department of Surgery, McGill University Health Centre, Montreal, QC, Canada; Cedars Breast Clinic, McGill University Health Centre, Montreal, QC, Canada.
authors.forename: Sarkis
authors.initials: S
authors.lastname: Meterissian
mesh_terms: D000328:Adult; D062005:Biopsy, Large-Core Needle; D001943:Breast Neoplasms / Q000473:pathology* / Q000601:surgery; D005260:Female; D018226:Fibroadenoma / Q000473:pathology* / Q000601:surgery; D006801:Humans; D008875:Middle Aged; D009367:Neoplasm Staging; D018225:Neoplasms, Fibroepithelial / Q000473:pathology* / Q000601:surgery; D003557:Phyllodes Tumor / Q000473:pathology* / Q000601:surgery; D011237:Predictive Value of Tests; D012189:Retrospective Studies
keywords: Breast neoplasms; Core needle biopsy; Excision; Fibroadenoma; Fibroepithelial lesion; Phyllodes tumor