Surgical management in phyllodes tumors of the breast: a systematic review and meta-analysis

Information is still controversial in the studies regarding the current optimal surgical management of phyllodes tumors (PTs) of the breast. Local recurrence (LR) may occur with an upgraded in the pathological grade, influencing the prognosis of patients with PT. This systematic review and meta-analysis aimed to investigate the association of LR risk with margin status and margin width which could have significant implications on the surgical management of PT.

Independent and comprehensive searches were performed by two authors through five databases including PubMed, Medline, Embase, ScienceDirect and Cochrane Library from January 1990 to October 2021. Studies investigating the association between margin width, margin status and LR rates were considered for inclusion. Study quality was evaluated using the Newcastle-Ottawa Scale (NOS). Meta-analysis was performed using RevMan5.3 software, and statistical heterogeneity was assessed using the Chi-square test and quantified using the I² statistic. Visual inspection of funnel plots was used to judge publication bias.

A total of 34 articles were included in this article, all of which with NOS scores above 5. Regardless of the PT grade, positive margin significantly increased the risk of LR [odds ratio (OR) 3.64, 95% confidence interval (CI): 2.60-5.12]. No significant difference was found in the risk of LR between the margins <1 and ≥1 cm (OR 1.39, 95% CI: 0.67-2.92). For benign and borderline PTs, there were no significant differences of the LR risk between breast-conserving surgery (BCS) and mastectomy (benign OR 0.68, 95% CI: 0.12-3.78; borderline OR 1.14, 95% CI: 0.29-4.51). While the LR risk was significantly increased by BCS for malignant PT (OR 2.77, 95% CI: 1.33-5.74).

Different surgical management strategies should be considered for different PT grades. BCS was a feasible option and margins <1 cm was not significantly associated with LR risk for all grade of PT. After BCS, benign PT with positive margin could adopt the "wait and watch" strategy with regular follow-up, while borderline and malignant PTs were expected to underwent re-excision to ensure negative margins. More studies are still needed to clarify and update the existing conclusions and improve the prognosis of PT patients.