AB142. Clinical utility of sentinel lymph node biopsy in ER+, node negative patients over the age of 65

Background: Current surgical management of breast cancer in patients with estrogen receptor (ER) positive disease who are clinically node negative involves a sentinel lymph node biopsy (SNLB) as a component of axillary staging. However, the Society of Surgical Oncology advise against the routine use of SLNB in elderly ER+, clinically node negative patients with T1/2 disease as it is unlikely to change treatment. The aim of our study was to assess the use of SLNB in elderly patients and the impact this had on adjuvant therapy decision making.

Methods: Data pertaining to patients over the age of 65 with ER+, clinically node negative, T1/2 breast cancer treated at our institution from 2005–2015 were included. Ethical approval was obtained. Statistical analysis was carried out using SPSS ver. 26.

Results: Four hundred and forty-eight patients were included (mean age 72.9, SD 5.9). Mean size of tumors were 21.88 mm, 335 patients (74.8%) had a SLNB while 113 patients did not (25.2%). Patients who had a SLNB were significantly younger than those who did not (72.4 years vs. 74.1, P=0.012). There was no statistically significantly different difference in administration of adjuvant chemotherapy between the SLNB group and those who did not receive SLNB (32.9% vs. 34.8%, P=0.42).

Conclusions: A significant number of patients in this elderly cohort received SLNB. SLNB appears to have minimal difference on the rate of adjuvant chemotherapy in this cohort.

Keywords: Breast cancer; elderly; endocrine therapy; sentinel lymph node