Survival impact of surgery and radiotherapy in malignant phyllodes tumors: Meta-Analysis of cohort studies

Background: Phyllodes tumors of the breast (PTs) are uncommon fibroepithelial lesions exhibiting tremendous biologic diversity, ranging from benign to highly aggressive malignant neoplasms. Surgical excision is the mainstay of treatment; however, the comparative survival benefit of mastectomy versus breast-conserving surgery (BCS) and the role of adjuvant postoperative radiotherapy (RT) in malignant PTs remain controversial. Existing evidence is fragmented, and clinical decision-making is largely extrapolated from retrospective series.

Methods: We conducted a PRISMA-compliant systematic review and meta-analysis of cohort studies evaluating survival outcomes in patients with primary malignant PTs treated with mastectomy or BCS, with or without postoperative RT. PubMed, Scopus, Cochrane Library, and PROSPERO databases were searched for eligible studies published between 2005 and 2025. Pooled hazard ratios (HRs) for overall survival and odds ratios (ORs) for cancer-related mortality were estimated using random-effects models in R software v.4.5.2. Meta-regression and propensity score-adjusted analyses were applied to account for tumor grade, surgical margins, and clinicopathologic confounders. In total, 8,779 patients with malignant PTs and available postoperative follow-up were included.

Results: Mastectomy, compared with breast-conserving surgery, was associated with significantly improved overall survival among patients with grade II–III malignant PTs (pooled HR=0.29, 95% CI=0.20–0.42; I²=72%, p=0.001). Postoperative radiotherapy did not confer a survival benefit and was associated with a higher risk of cancer-related mortality (pooled OR=3.27, 95% CI=2.55–4.17; I²=38%). These findings remained consistent across sensitivity and subgroup analyses adjusted for tumor grade and margin status.

Conclusions: Complete surgical resection remains the most critical determinant of survival in malignant phyllodes tumors. Our findings do not support the routine use of postoperative radiotherapy and suggest that RT should be reserved for carefully selected cases on an individualized basis. Overtreatment minimization, surgical treatment decisions, and future prospective trial designs, in a clinically significant manner, impact survivorship-focused cancer treatment and health care policy.