Intraoperative use of ketorolac or diclofenac is associated with improved disease-free survival and overall survival in conservative breast cancer surgery.

BACKGROUND An association between the use of non-steroidal anti-inflammatory drugs (NSAIDs) and better outcome after mastectomy and lung surgery for cancer has been recently suggested. In a retrospective analysis, we investigated the association between intraoperative NSAIDs use in conservative breast cancer surgery and breast cancer disease-free survival (DFS). Similarly, we also evaluated the association between breast cancer DFS and preoperative neutrophil:lymphocyte ratio (NLR). METHODS A retrospective analysis of a single-centre cohort was performed in breast cancer patients (n=720) with uni- and multivariate analyses, using a Cox regression model. RESULTS In conservative breast cancer surgery, the intraoperative use of NSAIDs (ketorolac or diclofenac) was associated with an improved DFS {hazard ratio (HR)=0.57 [95% confidence interval (CI): 0.37-0.89], P=0.01} and an improved overall survival (OS) [HR=0.35 (95% CI: 0.17-0.70), P=0.03]. In these patients, an NLR >3.3 (identified by a receiver-operating characteristic curve) was associated with a shorter DFS [HR=1.99 (95% CI: 1.16-3.41), P=0.01] and OS [HR=2.35 (95% CI: 1.02-5.43), P=0.046]. CONCLUSIONS Intraoperative NSAIDs and higher preoperative NLR are associated with improved outcome in conservative breast cancer surgery. Prospective, randomized trials to evaluate if these associations are causal are warranted.