title: Histologic changes associated with false-negative sentinel lymph nodes after preoperative chemotherapy in patients with confirmed lymph node-positive breast cancer before treatment.
abstract: BACKGROUND
  A wide range of false-negative rates has been reported for sentinel lymph node (SLN) biopsy after preoperative chemotherapy. The purpose of this study was to determine whether histologic findings in negative SLNs after preoperative chemotherapy are helpful in assessing the accuracy of SLN biopsy in patients with confirmed lymph node-positive disease before treatment.
  
  
  METHODS
  Eighty-six patients with confirmed lymph node-positive disease at presentation underwent successful SLN biopsy and axillary dissection after preoperative chemotherapy at a single institution between 1994 and 2007. Available hematoxylin and eosin-stained sections from patients with negative SLNs were reviewed, and associations between histologic findings in the negative SLNs and SLN status (true negative vs false negative) were evaluated.
  
  
  RESULTS
  Forty-seven (55%) patients had at least 1 positive SLN, and 39 (45%) patients had negative SLNs. The false-negative rate was 22%, and the negative predictive value was 67%. The negative SLNs from 17 of 34 patients with available slides had focal areas of fibrosis, some with associated foamy parenchymal histiocytes, fat necrosis, or calcification. These histologic findings occurred in 15 (65%) of 23 patients with true-negative SLNs and in only 2 (18%) of 11 patients with false-negative SLNs (P = .03, Fisher exact test, 2-tailed). The lack of these histologic changes had a sensitivity and specificity for identifying a false-negative SLN of 82% and 65%, respectively.
  
  
  CONCLUSIONS
  Absence of treatment effect in SLNs after chemotherapy in patients with lymph node-positive disease at initial presentation has good sensitivity but low specificity for identifying a false-negative SLN.
authors.affiliation: Department of Pathology, The University of Texas M. D. Anderson Cancer Center, Houston, TX, USA.
authors.forename: Alexandra S
authors.initials: AS
authors.lastname: Brown
authors.forename: Kelly K
authors.initials: KK
authors.lastname: Hunt
authors.forename: Jeannie
authors.initials: J
authors.lastname: Shen
authors.forename: Lei
authors.initials: L
authors.lastname: Huo
authors.forename: Gildy V
authors.initials: GV
authors.lastname: Babiera
authors.forename: Merrick I
authors.initials: MI
authors.lastname: Ross
authors.forename: Funda
authors.initials: F
authors.lastname: Meric-Bernstam
authors.forename: Barry W
authors.initials: BW
authors.lastname: Feig
authors.forename: Henry M
authors.initials: HM
authors.lastname: Kuerer
authors.forename: Judy C
authors.initials: JC
authors.lastname: Boughey
authors.forename: Christine D
authors.initials: CD
authors.lastname: Ching
authors.forename: Michael Z
authors.initials: MZ
authors.lastname: Gilcrease
mesh_terms: D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D001943:Breast Neoplasms / Q000188:drug therapy / Q000473:pathology* / Q000601:surgery; D002114:Calcinosis / Q000139:chemically induced; D005188:False Negative Reactions; D005260:Female; D005355:Fibrosis / Q000139:chemically induced; D006801:Humans; D008207:Lymphatic Metastasis / Q000473:pathology; D020360:Neoadjuvant Therapy; D012680:Sensitivity and Specificity; D021701:Sentinel Lymph Node Biopsy / Q000379:methods*