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.
PURPOSE
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.
['Galimberti|V|V|', 'Ribeiro Fontana|S K|SK|', 'Maisonneuve|P|P|', 'Steccanella|F|F|', 'Vento|A R|AR|', 'Intra|M|M|', 'Naninato|P|P|', 'Caldarella|P|P|', 'Iorfida|M|M|', 'Colleoni|M|M|', 'Viale|G|G|', 'Grana|C M|CM|', 'Rotmensz|N|N|', 'Luini|A|A|']
D000328:Adult D000368:Aged D001365:Axilla D001943:Breast Neoplasms D016208:Databases, Factual D018572:Disease-Free Survival D005260:Female D005500:Follow-Up Studies D006801:Humans D053208:Kaplan-Meier Estimate D008197:Lymph Node Excision D008198:Lymph Nodes D015412:Mastectomy, Segmental D008875:Middle Aged D015999:Multivariate Analysis D020360:Neoadjuvant Therapy D009361:Neoplasm Invasiveness D009367:Neoplasm Staging D016016:Proportional Hazards Models D012189:Retrospective Studies D018570:Risk Assessment D021701:Sentinel Lymph Node Biopsy D016019:Survival Analysis D013997:Time Factors
Sentinel node biopsy Neoadjuvant treatment Axillary dissection Primary breast cancer