title: Sentinel lymph node biopsy is not warranted following a core needle biopsy diagnosis of ductal carcinoma in situ (DCIS) of the breast.
abstract: BACKGROUND
  The role of sentinel lymph node biopsy (SLNB) in ductal carcinoma in situ (DCIS) is controversial. This study evaluates the risk of clinically relevant SLN metastasis following a core needle biopsy (CNB) diagnosis of pure DCIS.
  
  
  METHODS
  Cases that underwent SLNB following a CNB diagnosis of pure DCIS at our institution over a 4.5 year period were evaluated. Parameters including the DCIS characteristics on CNB, the rate of upstaging to invasive carcinoma at excision and the SLNB result were recorded.
  
  
  RESULTS
  Of 296 patients with a CNB diagnosis DCIS, 181 had SLNB (62%). The rate of invasion at excision in those undergoing SLNB was 30% (54/181). SLN metastasis was detected in 7/181 cases (4%), including 6 cases with isolated tumour cells only (3.5%) and only 1 case with a macro-metastatic deposit (0.5%).
  
  
  CONCLUSIONS
  The risk of clinically significant SLN metastasis following a CNB diagnosis of DCIS is extremely low, despite a relatively high rate of upstaging to invasive carcinoma at excision. Our findings support the opinion that SLNB is not warranted following a CNB diagnosis of DCIS, particularly for those patients undergoing breast conservation surgery.
authors: Department of Histopathology, Cork University Hospital, Wilton, Cork, Ireland.
authors: Susan
authors: S
authors: Prendeville
authors: Department of Histopathology, Cork University Hospital, Wilton, Cork, Ireland.
authors: Ciara
authors: C
authors: Ryan
authors: Department of Histopathology, Cork University Hospital, Wilton, Cork, Ireland.
authors: Linda
authors: L
authors: Feeley
authors: Department of Histopathology, Cork University Hospital, Wilton, Cork, Ireland.
authors: Fionnuala
authors: F
authors: O'Connell
authors: Department of Histopathology, Cork University Hospital, Wilton, Cork, Ireland.
authors: Tara Jane
authors: TJ
authors: Browne
authors: Department of Surgery, Cork University Hospital, Wilton, Cork, Ireland; BreastCheck Southern Unit (National Cancer Screening Service), Infirmary Road, Cork, Ireland.
authors: Martin J
authors: MJ
authors: O'Sullivan
authors: Department of Histopathology, Cork University Hospital, Wilton, Cork, Ireland; BreastCheck Southern Unit (National Cancer Screening Service), Infirmary Road, Cork, Ireland. Electronic address: Michael.bennett@hse.ie.
authors: Michael W
authors: MW
authors: Bennett
mesh_terms: D062005:Biopsy, Large-Core Needle / Q000706:statistics & numerical data*; D001943:Breast Neoplasms / Q000473:pathology*; D002285:Carcinoma, Intraductal, Noninfiltrating / Q000556:secondary*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008207:Lymphatic Metastasis; D015412:Mastectomy, Segmental; D021701:Sentinel Lymph Node Biopsy / Q000706:statistics & numerical data*
keywords: Core needle biopsy; Ductal carcinoma in situ; Sentinel lymph node