Repeat recurrence and malignant transition of phyllodes tumors of the breast.

BACKGROUND

This study aimed to assess their characteristics and clinical course of each histologic type of the behavior of phyllodes tumor (PT).

METHODS

We retrospectively reviewed 124 patients with PTs who underwent surgical treatment from 2003 to 2011. PTs were classified as benign, borderline, and malignant using surgical specimens. The clinicopathological characteristics according to solitary and multiple lesions on ipsilateral breast and histological change after local recurrence were examined.

RESULTS

The median patient age was 42 years (range 12-72 years). The final pathologic diagnosis was benign PTs in 95 patients (76.6%), borderline PTs in 21 (16.9%), and malignant PTs in 8 (6.5%). The size of benign PTs [median 4.2 cm (range 1-21 cm)] was significantly smaller than that of malignant PTs [median 11.3 cm (range 6-27 cm)] (p < 0.001). Eight of the 95 benign PTs (8.4%) had multiple lesions, while all malignant PTs had solitary lesion. With a median follow-up period of 45 months, five patients with malignant PTs (62.5%) developed distant metastases while 13 patients with benign PTs (13.5%) and 6 patients with borderline PTs (28.6%) had local recurrence only without malignant transition. The median overall survival period of those with malignant PTs was 22.5 months (range 5-109 months).

CONCLUSIONS

Histologically benign and borderline PTs had a good prognosis without malignant transition even after developing repeat recurrence in contrast with malignant PTs that might be a solitary lesion.