Risk Factors of Local Recurrence in Phyllodes Tumor of the Breast according to the Clinicopathological Characteristics

ABSTRACT

PURPOSE: Phyllodes tumor is a rare fibroepithelial disease of the breast that is classified as benign, borderline malignant, or malignant according to the pathological characteristics. To clarify diagnostic criteria for these groups, we analyzed the clinico-pathological characteristics of phyllodes tumors and the risk factors for local recurrence after surgery. METHODS: Between January 1997 and March 2003, we included 70 cases of recurring, pathologically-confirmed phyllodes tumors after surgery. Medical records were reviewed retrospectively for clinical characteristics and pathologic findings. RESULTS: The mean follow up period was 69.3 months (range 45.4 to 119.3 months) and mean age, 39.4 years old (range 18 to 63 years old). Benign phyllodes tumors were present in 45 cases (64.3%), borderline malignant tumors in 15 cases (21.4%), and malignant tumors in 10 cases (14.3%). A local recurrence developed in 9 cases (12.9%), with three of these cases benign (33.3%), 5 cases were borderline malignant (55.6%), and 1 case was malignant (11.1%). Borderline malignant cases showed a higher local recurrent rate (6.7%, 33.3%, and 10.0%, P=0.027). The local recurrence rate between the tumor-positive or close (<1 mm) resection margins and non-involved cases was different for benign (7.7% vs. 6.3%, P=0.031) and borderline malignant cases (60.0% vs. 20.0%, ns). CONCLUSION: Pathologic classification and small resection margins are risk factors for local recurrence in phyllodes tumors. Therefore, borderline malignant phyllodes tumors require wide excision with a sufficient resection margin or a mastectomy to prevent local recurrence.