Does surgical margin status truly affect local recurrence in benign and borderline phyllodes tumors of the breast?

Phyllodes tumors of the breast are rare and classified into three groups-benign, borderline, and malignant-based on their malignant potential. Surgical resection is the primary treatment modality; however, the necessity of clear surgical margins remains a topic of debate in the literature. This study aimed to evaluate the relationship between surgical margin status and local recurrence in benign and borderline phyllodes tumors.

A total of 177 patients diagnosed with phyllodes tumors from two centers were included. Patients were analyzed based on demographic, clinical, pathological, and survival data.

The median age was 38 years (range: 15-78), and all patients were female. The most commonly performed breast surgery was wide local excision in 173 patients (97.7 %). Final pathological examination revealed that 136 patients (76.8 %) had benign phyllodes tumors, while 41 patients (23.2 %) had borderline phyllodes tumors. The median pathological tumor diameter was 35 mm (IQR: 27-55 mm). During a median follow-up of 60 months, local recurrence occurred in 12 patients (6.8 %), while no systemic metastasis or tumor-related death was observed. Patients with borderline phyllodes tumors had a higher local recurrence rate and shorter recurrence-free survival (RFS) (p = 0.022 and p = 0.013, respectively). Cox regression analysis identified tumor type as the only independent factor affecting RFS, with borderline phyllodes tumors demonstrating a shorter RFS compared to benign phyllodes tumors (p = 0.015).

Surgical margin status was not associated with local recurrence in benign and borderline phyllodes tumors. Therefore, re-excision decisions based on margin proximity or positivity should be individualized.