Evaluating the Clinical Utility of Routine Sentinel Lymph Node Biopsy and the Value of Adjuvant Chemotherapy in Elderly Patients Diagnosed With Oestrogen Receptor Positive, Clinically Node Negative Breast Cancer

• Main Authors: Matthew G Davey, Éanna J Ryan, Daniel Burke, Kevin McKevitt, Peter F McAnena, Michael J Kerin, Aoife J Lowery
• Format: Article
• Language: English
• Published: SAGE Publishing 2021-06-01
• Series: Breast Cancer: Basic and Clinical Research
• Online Access: https://doi.org/10.1177/11782234211022203

Background: Sentinel lymph node biopsy (SLNB) provides staging information and guides adjuvant therapy in early breast cancer (EBC). Routine SLNB in oncogeriatricians with low-risk EBC remains controversial. Aims: To evaluate axillary management in elderly patients diagnosed with oestrogen receptor positive (ER+), clinically lymph node negative (cLN−) EBC, and to assess whether SLNB affects further axillary management or adjuvant chemotherapy (ACTX) decision making. Methods: Female patients aged > 65 years, diagnosed with ER+, human epidermal growth factor receptor-2 negative (HER2−), and cLN− breast cancer (BC), who underwent surgery and SLNB were included. Clinicopathological predictors of ACTX and completion axillary lymph node dissection (CALND) were determined. Kaplan-Meier analyses assessed survival outcomes. Results: A total of 253 patients were included (median age: 72 years, range: 66-90), all underwent SLNB; 50 (19.8%) had lymphatic metastasis on SLNB (SLNB+). Of these, 19 proceeded to CALND (38.0%), 10 (52.6%) of whom had further axillary disease (ALND+). 20 of the 50 SLNB+ patients received ACTX (40.0%) as did 31 of the 203 SLNB− patients (15.2%) ( P  < .001). Oncotype DX (ODX) testing was utilized in 82 cases (32.8%). Younger age ( P  < .001), SLNB+ ( P  < .001) and ODX score ( P  = .003) were all associated with ACTX prescription. ODX > 25 (OR: 4.37, 95% CI: 1.38-13.80, P  = .012) independently predicted receiving ACTX. Receiving ACTX and proceeding to CALND did not improve disease-free ( P  = .485 and P  = .345) or overall survival ( P  = .981 and P  = .646). Conclusions: Routine SNLB may not be necessary in elderly patients diagnosed with ER+, cLN− EBC. Future oncogeriatric practice is likely to see genomic testing guiding ACTX prescription in this group.