title: Sentinel node biopsy after neoadjuvant treatment in breast cancer: Five-year follow-up of patients with clinically node-negative or node-positive disease before treatment.
abstract: OBJECTIVE
  It is controversial whether sentinel node biopsy (SNB) without axillary dissection (AD) should be performed in cN1/2 breast cancer patients who become cN0 after neoadjuvant treatment, since the false negative rate (FNR) may be unacceptably high. We assessed outcomes to address this issue.
  
  
  METHODS
  We retrospectively assessed 396 cT1-4, cN0/1/2 patients, who became or remained cN0 after neoadjuvant treatment and underwent SNB with at least one sentinel node (SN) found, and AD not performed if the SN was negative.
  
  
  RESULTS
  After a median follow-up of 61 months (interquartile range 38-82), five-year overall survival was 90.7% (95% CI, 87.7-93.7) in the whole cohort, 93.3% (95% CI, 90.0-96.6) in those initially cN0, and 86.3% (95% CI, 80.6-92.1) in those initially cN1/2 (P = 0.12). Axillary failure occurred in only 1 (0.7%) initially cN1/2 patient who became cN0. In initially cN0 patients, and also initially cN1/2 patients who responded well to neoadjuvant treatment (ypT0/ypTx), SN-negativity was a significant predictor of good outcome, consistent with the known prognostic significance of axillary status, and suggesting that SN status accurately reflected axillary status. By contrast, in initially cN1/2 patients found to be ypT1/2/3, SN status (and whether or not AD was performed) had no influence on survival.
  
  
  CONCLUSIONS
  These findings suggest that SNB is acceptable in cN1/2 patients who become cN0 after neoadjuvant therapy.
authors.affiliation: Division of Senology, European Institute of Oncology, Via Ripamonti 435, 20141 Milan, Italy. Electronic address: Viviana.galimberti@ieo.it.
authors.forename: V
authors.initials: V
authors.lastname: Galimberti
authors.affiliation: Division of Senology, European Institute of Oncology, Via Ripamonti 435, 20141 Milan, Italy.
authors.forename: S K
authors.initials: SK
authors.lastname: Ribeiro Fontana
authors.affiliation: Division of Epidemiology and Biostatistics, European Institute of Oncology, Via Ripamonti 435, 20141 Milan, Italy.
authors.forename: P
authors.initials: P
authors.lastname: Maisonneuve
authors.affiliation: Division of Senology, European Institute of Oncology, Via Ripamonti 435, 20141 Milan, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Steccanella
authors.affiliation: Division of Senology, European Institute of Oncology, Via Ripamonti 435, 20141 Milan, Italy.
authors.forename: A R
authors.initials: AR
authors.lastname: Vento
authors.affiliation: Division of Senology, European Institute of Oncology, Via Ripamonti 435, 20141 Milan, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Intra
authors.affiliation: Division of Senology, European Institute of Oncology, Via Ripamonti 435, 20141 Milan, Italy.
authors.forename: P
authors.initials: P
authors.lastname: Naninato
authors.affiliation: Division of Senology, European Institute of Oncology, Via Ripamonti 435, 20141 Milan, Italy.
authors.forename: P
authors.initials: P
authors.lastname: Caldarella
authors.affiliation: Division of Medical Senology, European Institute of Oncology, Via Ripamonti 435, 20141 Milan, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Iorfida
authors.affiliation: Division of Medical Senology, European Institute of Oncology, Via Ripamonti 435, 20141 Milan, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Colleoni
authors.affiliation: Department of Pathology, European Institute of Oncology, Via Ripamonti 435, 20141 Milan, Italy; University of Milan, School of Medicine, Milan, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Viale
authors.affiliation: Division of Nuclear Medicine, European Institute of Oncology, Via Ripamonti 435, 20141 Milan, Italy.
authors.forename: C M
authors.initials: CM
authors.lastname: Grana
authors.affiliation: Division of Epidemiology and Biostatistics, European Institute of Oncology, Via Ripamonti 435, 20141 Milan, Italy.
authors.forename: N
authors.initials: N
authors.lastname: Rotmensz
authors.affiliation: Division of Senology, European Institute of Oncology, Via Ripamonti 435, 20141 Milan, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Luini
mesh_terms: D000328:Adult; D000368:Aged; D001365:Axilla / Q000601:surgery; D001943:Breast Neoplasms / Q000401:mortality* / Q000473:pathology / Q000628:therapy*; D016208:Databases, Factual; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D008197:Lymph Node Excision / Q000379:methods*; D008198:Lymph Nodes / Q000473:pathology* / Q000601:surgery; D015412:Mastectomy, Segmental / Q000379:methods; D008875:Middle Aged; D015999:Multivariate Analysis; D020360:Neoadjuvant Therapy / Q000379:methods*; D009361:Neoplasm Invasiveness / Q000473:pathology; D009367:Neoplasm Staging; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D018570:Risk Assessment; D021701:Sentinel Lymph Node Biopsy / Q000379:methods*; D016019:Survival Analysis; D013997:Time Factors
keywords: Axillary dissection; Neoadjuvant treatment; Primary breast cancer; Sentinel node biopsy