Original ResearchFeasibility, accuracy and prognosis of sentinel lymph node biopsy before neoadjuvant therapy in breast cancer. A prospective study

- All 123 patients undergoing NAT had their SLN successfully identified on technetium mapping before treatment.
- SLNB before NAT reduced the number of patients undergoing axillary lymph node clearance by nearly three quarters (72.4%)
- Sentinel lymph node involvement did not affect survival during follow-up for a median of 40 months.
- Disease Free Survival was associated with molecular-like subtypes and response to NAT.

Background and objectiveIt remains controversial whether sentinel lymph node biopsy (SLNB) should be performed before or after neoadjuvant therapy (NAT). We aimed to evaluate the feasibility and accuracy of SLNB before NAT at a single institution, and to determine its relation to patient prognosis.MethodsA prospective study of T1c-T2-T3 N0 breast cancer patients, after ultrasound examination, who underwent SLNB prior to NAT. Overall, disease-specific and disease-free survival were calculated by Kaplan-Meier curves.ResultsSLNB before NAT was performed in 123 patients from December 2006 to May 2014. The identification rate was 100%. SLNB was positive in 42.3% of cases (27.6% macrometastases). NAT was chemotherapy in 88.6% of cases and endocrine-therapy in 11.4%. Lymphadenectomy was avoided in 72.4% of cases. Median follow-up was 40 months (range 8-100). Overall and disease-free survival was 90.2% and 88.6% respectively.SLN involvement was not related to patient outcome (p 0.72); however there were significant differences in survival according to molecular-like subtypes (p < 0.025) and NAT response (p < 0.0001).ConclusionsSLNB prior to NAT is an accurate method of axillary staging associated with a high identification rate. It avoided lymphadenectomy in more than 70% of patients. SLN involvement did not worsen the prognosis in our cohort.