Axillary lymph node dissection for patients with invasive breast cancer at Charlotte Maxeke Johannesburg academic hospital and Chris Hani Baragwanath academic hospital

Abstract

Background: The extent of axillary surgery correlates with its morbidity and sentinel lymph node biopsy (SLNB) has become the standard of care in clinically node-negative (cN0) breast cancer patients. Objectives: This study aims to 1) evaluate the application of SLNB and axillary lymph node dissection (ALND) and determine the prevalence of pathological node negative (pN0) ALND’s and 2) determine the factors associated with pN0 ALND outcome in two Johannesburg breast units. Methods: We included female patients with primary breast cancer who underwent axillary surgery in the breast units at Charlotte Maxeke Johannesburg Academic Hospital (CMJAH) and Chris Hani Baragwanath Academic Hospital (CHBAH) from March 2013 to March 2015. Univariate and multivariable logistic regression models were used to determine factors associated with pN0 ALND. Results: Five hundred and five patients were included and 344 patients (68.1%) were staged clinically node-positive (cN1), 161 patients (31.9%) were assessed as cN0 and deemed eligible for SLNB. Sensitivity of clinical nodal staging was 85.9% with a positive predictive value (PPV) of 76.5%. The majority of patients (313, 61.9%) underwent primary surgery while 192 patients (38.1%) underwent surgery after Neoadjuvant chemotherapy (NACT). We performed 118 SLNBs and 387 ALNDs. There were 97 pN0 ALND’s and of all the SLNB’s and ALND’s, a total of 199 were pN0 tumours. Risk was not increased after NACT (OR 1.06, p=0.790). We identified a significant risk in patients with triple-negative and Human epidermal growth factor-2 (HER-2) enriched subtypes compared to hormone receptor-positive patients (OR 3.05, 95% CI: 1.6-5.7, p=0.001 and OR 2.25, 95% CI: 1.1-4.8, p=0.035). Conclusions: The prevalence of pN0 ALND was 25.1%. Hormone receptor negative tumours were associated with a higher pN0 ALND outcome as compared to luminal cancers. Preoperative nodal assessment needs to be optimised and include pathological confirmation. SLNB needs to be extended to patients after NACT despite resourceconstraints.