Sentinel Lymph Node Biopsy In Women Over 70: Evaluation Of Rates Of Axillary Staging And Impact On Adjuvant Therapy In Elderly Women
*Elise Di Lena, *Alen Antoun, *Natasha Barone, *Uyen Do, Sarkis Meterissian
McGill University, Montreal, QC, Canada
OBJECTIVE(S):The 2016 Society of Surgical Oncology Choosing Wisely guidelines recommended against routine sentinel lymph node biopsy (SLNB) in women ≥ 70 years old with favorable histology and clinical staging, given that SLNB does not decrease locoregional recurrence or cancer mortality in this patient population. The objective of this study was therefore to evaluate the use of SLNB and its effect on management in elderly patients at an academic breast cancer center. METHODS:A retrospective analysis of a prospectively maintained database of breast cancer patients was performed evaluating female patients ≥70 years old with stage I or II, clinically node-negative, hormone-receptor positive and HER2 negative disease undergoing upfront breast cancer surgery between 2017- 2019. Primary outcome was rate of SLNB. Secondary outcome was effect of SLNB on adjuvant therapy.
RESULTS:148 patients met inclusion criteria. Median age was 76 (IQR 73-81) in the overall cohort and 73% of patients underwent lumpectomy. On final pathology, 58.8% had invasive ductal carcinoma and median tumor size was 15mm (IQR 10-24). 120 (81.1%) patients underwent SLNB; of these, 32 (26.7%) were positive for isolated tumor cells (3 patients), N1mi (7 patients) or N1a disease (22 patients) (SLNB+). On multivariate regression analysis, patients undergoing SLNB were more likely to be younger (OR 0.88, 95% CI 0.80-0.95). Tumor grade on biopsy, clinical T-stage, and breast surgery performed had no effect on odds of undergoing SLNB. The major risk factor for SLNB+ was lymphovascular invasion (OR 8.60, 95% CI 3.25-24.8). Patients with SLNB+ were more likely to receive adjuvant radiation therapy (OR 2.75, 95% CI 1.00-8.28) adjuvant axillary radiation (OR 31.74, 95% CI 4.67-358.89), and adjuvant chemotherapy although the latter was not statistically significant (OR 2.65, 95% CI 0.25-31.47).
CONCLUSIONS:Despite the 2016 Choosing Wisely guidelines, over 80% of patients ≥70 years old underwent SLNB at our institution. If SLNB+, this is associated with over 2-fold higher rates of adjuvant radiotherapy and over 30-fold higher rates of adjuvant radiation to the axilla.
| Variables | Overall (n=148) | Without SLNB (n=28) | With SLNB (n=120) | p-value |
| Completion ALND | 1 (0.7) | - | 1 (3.6) | - |
| Adjuvant endocrine therapy | - | - | - | 0.298 |
| Yes | 111 (75.0) | 19 (67.9) | 92 (76.7) | - |
| No | 26 (17.6) | 5 (17.9) | 21 (17.5) | - |
| Patient declined | 11 (7.4) | 4 (14.3) | 7 (5.8) | - |
| Adjuvant chemotherapy | 9 (6.1) | 1 (3.6) | 8 (6.7) | 0.537 |
| Adjuvant radiotherapy | 81 (54.7) | 11 (39.3) | 70 (58.3) | 0.068 |
| Adjuvant axillary radiation | 12 (9.7) | 0 (0) | 12 (11.9) | 0.082 |
| Lymphedema | 4 (3.8) | 0 (0) | 4 (3.8) | 0.842 |
Back to 2022 Abstracts