Role of neoadjuvant chemotherapy in breast cancer patients: Systematic review and meta-analysis

Background: The present systematic review and meta-analysis critically assessed the impact of neoadjuvant chemotherapy (nACT) in comparison to ACT in breast cancer patients in terms of oncological and functional outcomes. Methods: Randomized controlled trials comparing NACT with ACT in breast cancer patients were identified through Medline and Cochrane Register of Controlled Trials on January 21, 2016. Cochrane risk of bias assessment tool was used to assess the risk of bias. Meta-analysis was performed using fixed-effects or random-effects method depending on heterogeneity (I2). Grading of the evidences was also done. Subgroup meta-analysis on the basis of total preoperative chemotherapy or sandwich chemotherapy was also performed. Results: The present meta-analysis shows increased breast-conserving surgery (BCS) rate (n = 9, risk ratio [95% confidence interval (CI)] = 1.19 [1.03–1.37]) with NACT. Further, NACT was found equally effective regarding overall survival (n = 15, hazard ratio [HR] [95% CI] = 0.98 [0.89–1.08]), disease-free survival (DFS) (n = 14, HR [95% CI] = 1.01 [0.86–1.18]), and distant metastasis (n = 13, HR [95% CI] = 0.97 [0.82–1.16]). Although locoregional recurrence (LRR) rate was noted to be significantly higher in NACT group (n = 15, HR [95% CI] = 1.23 [1.06–1.43]), its significance disappeared (n = 13, HR [95% CI] = 1.17 [0.98–1.40]) by excluding the trials where surgery was not provided for patients with complete tumor response. After excluding such trials, preoperative NACT was associated with increased BCS with similar LRR in ACT group. Discussion: NACT has no major impact on breast cancer survival. However, it is associated with increased BCS rates. NACT downgrades tumor size facilitating more BCSs without increasing LRR. The evidences were graded for all outcomes as high except DFS and BCS as moderate.