Time from Completion of Neo‐adjuvant Chemotherapy to Surgery: Effects on Outcomes in Breast Cancer Patients

There is no consensus on the ideal time interval between the completion of neo-adjuvant chemotherapy (NAC) and definitive surgery for patients with breast cancer. This study sought to determine the ideal time interval from completion of systemic therapy to surgery in an attempt to define a best practice. A retrospective analysis of all patients undergoing NAC for Stage I-III breast cancer from 1998-2010 was undertaken. Analysis of all demographic and clinical information was performed, with emphasis on interval from completion of systemic therapy to definitive surgical management. Three hundred and eighty eight patients met the inclusion criteria with a median age of 50 (61.9% white, 33.8% black and 4.3% other). Overall, 2.8% of patients were Stage I, 57.2% Stage II and 40% Stage III. Median follow-up was 85 months. Pathologic response to systemic therapy was complete in 20.6%, partial in 67.8% and no response or progression in 11.6%; responders (pCR or pPR) were noted to have significantly improved Disease free survival (DFS) and Overall survival (OS). Patients undergoing surgical intervention 4-6 weeks after completion of NAC were noted to have a trend towards improved DFS and OS on multivariable analysis. These findings were also observed in the nonlinear relationship between survival risk and surgery time window using martingale residual plots. Timing of surgical intervention following the receipt of NAC may not appear to affect DFS or OS.