Long-term survival in patients with node-positive breast cancer who undergo sentinel lymph node biopsy alone after neoadjuvant chemotherapy: meta-analysis

Abstract

Background: Sentinel lymph node biopsy (SLNB) after neoadjuvant chemotherapy (NACT) in patients with breast cancer who are initially node-positive but convert to clinically/radiologically node-negative remains controversial. The primary aim was to assess pooled 5-year disease-free (DFS) and overall (OS) survival for patients who are initially node-positive but have a negative SLNB after NACT, and do not proceed to axillary lymph node dissection (ALND). Methods: The study was performed using PRISMA guidelines. A systematic literature search of relevant databases was conducted. The Der Simonian–Laird and Cochran–Mantel–Haenszel methods were used to calculate weighted pooled estimates for OS and DFS for this group compared with patients who had NACT and proceeded to ALND after a negative or positive SLNB. Results: Seven studies involving 915 patients who had a negative SLNB after NACT were included. Pooled estimates of 5-year DFS and OS in patients with a negative SLNB after NACT were 86 (95 per cent c.i. 82.1 to 90.3) and 93.1 (87.8 to 97.0) per cent respectively. Patients with a positive SLNB who underwent ALND had reduced 5-year DFS (OR 0.49, 95 per cent c.i. 0.35 to 0.69; P < 0.001) and OS (OR 0.41, 0.16 to 1.02; P = 0.06) compared with those who had a negative SLNB after NACT. There were no differences in DFS for patients who had a negative SLNB only compared with those undergoing ALND with a pCR (OR 1.65, 0.71 to 3.79; P = 0.24). Conclusion: Patients who are initially node-positive and who achieve a complete clinical/radiological axillary response after NACT with a subsequent negative SLNB have high rates of DFS and OS after 5 years. Patients with residual disease have significantly reduced DFS and further axillary treatment may still be warranted.