[Prognosis analysis of local recurrence after excision of breast phyllodes tumors]

Objective: To examine treatment outcomes of breast phyllodes tumors and the prognosis factors of local recurrence. Methods: This retrospective cohort study included 276 patients who underwent surgical resection at Breast Center, Peking University People's Hospital from January 2011 to December 2019. Tumor subtype and histopathological features were determined from pathology reports, and the deadline of follow-up was September 30^th, 2020. All 276 patients underwent open surgery, including 17 patients of mastectomy, and 259 patients of lumpectomy. The enrolled patients were all female, with age of (41.5±11.3) years (rang: 11 to 76 years), and tumor diameter of 35(28) mm (M(Q)). The Kaplan-Meier method and Log-rank test were used for survival analysis. The multivariate analysis was implemented using the Cox proportional hazard model. Results: According the pathologic test, there were 191 patients of benign phyllodes tumor, 67 patients of borderline tumor and 18 patients of malignant tumor. There were 249 patients with a follow-up of more than 6 months, and 14.1% (35/249) had local recurrence. The time-to-recurrence was (28.6±22.2) months (range: 2 to 96 months), (29.1±18.1) months (range: 2 to 80 months), (32.1±30.1) months (range: 5 to 96 months) and (12.0±6.9) months (range: 8 to 20 months) for benign, borderline and malignant phyllodes tumors. Tumor diameter (≥100 mm vs.<50 mm, HR=3.968, 95%CI: 1.550 to 10.158, P=0.004) and malignant heterologous element (yes vs. no, HR=26.933, 95%CI: 3.105 to 233.600, P=0.003) were prognosis factors of local recurrence. One death from malignant phyllodes occurred after distant metastasis. The 3-year disease-free survival rates of benign, borderline and malignant phyllodes tumor were 88.2%, 81.7% and 81.4% (P=0.300). Conclusion: Phyllodes tumors have a considerable local recurrence rate, which may be associated with tumor diameter and malignant heterologous element.