367P - Sentinel lymph node biopsy (SLNB) in patients with locally advanced breast cancer (LABC): Descriptive, inferential and survival analysis

Background

The objective was to perform a descriptive, inferential and overall survival analysis of patients with LABC who underwent SLNB.

Methods

Retrospective study(January/12-December/22) in patients with LABC selected for SLNB with: initial clinical and radiological tumor and lymph node staging(TNM-AJCC-7&8-Edition), histological types, prognostic tumor markers, with evaluation of the response(radiological & pathological) of the tumor and lymph nodes after neoadjuvant chemotherapy(NACT). We performed a descriptive, inferential and survival analysis.

Results

141patients with LABC met inclusion criteria: 128(91%)Infiltrating Ductal Carcinoma, 7(5%)Infiltrating Lobular Carcinoma, 2(1%) Infiltrating Ductal Carcinoma in-situ, and 1case(1% each) of: tubular, medullary, mucinous and colloid carcinoma. The TNM staging before NACT was: T1:14(9.9%)patients; T2:95(67.4%); T3:27(19.2%) and T4:5(3.5%). 89(63.1%)patients were cN(+) and 52(36.9%) were cN(0). Intrinsic subtypes were: Luminal-A 10(7.1%) patients, Luminal-B 26(18.4%); Luminal-B-Her2 34(22%); Her2 31(28.4%) and 40(24.1%)Triple negative. Histological grades (HG) were: grade I 5(3.5%)patients, grade II 53(37.6%), and grade III 83(58.9%). We obtained 46(32.6%)SLNB(+), 85(60.3%)SLNB(-) and in 10(7.1%)there was no migration (NM). We performed 93 lymphadenectomies(LDN): 44 SLNB(+); 39 SLNB(-) and 10-NM. We obtained 29LDN(+):19SLNB(+), 6NM and 4SLNB(-). We obtained 64LDN(-): 25SLNB(+), 4NM and 35SLNB(-). 8-patients died: 3LDN(+): 2SLNB(+) and 1NM; 4-LDN(-): 2SLNB(+) and 2SLNB(-); and 1 SLNB(-) without LDN. 46-patients(51.7%) went from cN(+) to pN0. In the inferential analysis we found a statistically significant correlation between the SLNB result and the intrinsic subtype (p<0.001), with Luminal-B-Her2 subtypes and triple negative patients as those with the most SLNB(-) results. Detection rate(DR) was 95.3%. False negative rate (FNR) was 8%, considering SLNB(+) as a true positive. The survival time for patients with SLNB(+) was 111 months, for SLNB(-) it was 127 months (±2.4) and for patients with NM it was 95 months.

Conclusions

Our DR was 95%, FNR was 8%, mortality was 5%, and overall survival with SLNB(-) was 127 months.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

Hospital Universitario Cruces.

Funding

Has not received any funding.

Disclosure

The author has declared no conflicts of interest.