The diagnostic performance of sentinel lymph node biopsy in pathologically confirmed node positive breast cancer patients after neoadjuvant systemic therapy: A systematic review and meta-analysis.
OBJECTIVE
To provide a systematic review and meta-analysis of studies investigating sentinel lymph node biopsy after neoadjuvant systemic therapy in pathologically confirmed node positive breast cancer patients.


METHODS
Pubmed and Embase databases were searched until June 19th, 2015. All abstracts were read and data extraction was performed by two independent readers. A random-effects model was used to pool the proportion for identification rate, false-negative rate (FNR) and axillary pCR with 95% confidence intervals. Subgroup analyses affirmed potential confounders for identification rate and FNR.


RESULTS
A total of 997 abstracts were identified and eventually eight studies were included. Pooled estimates were 92.3% (90.8-93.7%) for identification rate, 15.1% (12.7-17.6%) for FNR and 36.8% (34.2-39.5%) for axillary pCR. After subgroup analysis, FNR is significantly worse if one sentinel node was removed compared to two or more sentinel nodes (23.9% versus 10.4%, p = 0.026) and if studies contained clinically nodal stage 1-3, compared to studies with clinically nodal stage 1-2 patients (21.4 versus 13.1%, p = 0.049). Other factors, including single tracer mapping and the definition of axillary pCR, were not significantly different.


CONCLUSIONS
Based on current evidence it seems not justified to omit further axillary treatment in every clinically node positive breast cancer patients with a negative sentinel lymph node biopsy after neoadjuvant systemic therapy.
Department of Radiology, Maastricht University Medical Center+, Maastricht, The Netherlands; Department of Surgery, Maastricht University Medical Center+, Maastricht, The Netherlands; GROW - School for Oncology and Developmental Biology, Maastricht University Medical Center+, Maastricht, The Netherlands. Electronic address: Thiemovn@gmail.com.
T J A
TJ
van Nijnatten
Department of Radiology, Maastricht University Medical Center+, Maastricht, The Netherlands; Department of Surgery, Maastricht University Medical Center+, Maastricht, The Netherlands; GROW - School for Oncology and Developmental Biology, Maastricht University Medical Center+, Maastricht, The Netherlands.
R J
RJ
Schipper
Department of Radiology, Maastricht University Medical Center+, Maastricht, The Netherlands.
M B I
MB
Lobbes
Department of Epidemiology, Maastricht University Medical Center+, Maastricht, The Netherlands.
P J
PJ
Nelemans
Department of Radiology, Maastricht University Medical Center+, Maastricht, The Netherlands; GROW - School for Oncology and Developmental Biology, Maastricht University Medical Center+, Maastricht, The Netherlands.
R G H
RG
Beets-Tan
Department of Surgery, Maastricht University Medical Center+, Maastricht, The Netherlands; GROW - School for Oncology and Developmental Biology, Maastricht University Medical Center+, Maastricht, The Netherlands.
M L
ML
Smidt
D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D001365:Axilla; D001943:Breast Neoplasms / Q000188:drug therapy / Q000473:pathology*; D018270:Carcinoma, Ductal, Breast / Q000188:drug therapy / Q000473:pathology*; D018275:Carcinoma, Lobular / Q000188:drug therapy / Q000473:pathology*; D005260:Female; D006801:Humans; D008197:Lymph Node Excision; D008198:Lymph Nodes / Q000473:pathology*; D020360:Neoadjuvant Therapy; D009367:Neoplasm Staging; D021701:Sentinel Lymph Node Biopsy
Breast cancer; Clinically node positive patients; Neoadjuvant systemic therapy; Sentinel lymph node biopsy