gms | German Medical Science

Introduction: The “Cystosarcoma phyllodes” of the breast is a rare entity which accounts for 0.5 % of all breast neoplasms. The diagnosis should be considered in all rapidly growing breast nodules. We reviewed all cases of this rare disease that presented at our hospital in the last 20 years.

Patients and Methods: The data of 5270 patients with primary breast neoplasms treated in our department between 1984 and 2005 were retrospectively analyzed for the histopathologic diagnosis of a cystosarcoma phyllodes.

Results: 33 patients with cystosarcoma phyllodes of the breast could be identified. The median age at diagnosis was 47 years. Median follow up was 86 months. The tumors were classified histologically into benign (40%), borderline (27%) and malignant tumors (33%) based on standardized criteria; 3 tumors were unclassified. Surgery was conducted as a breast conserving (58%) or radical surgery (mastectomy) (42%). Only one patient was treated with adjuvant radiotherapy after primary surgery. Median tumor size was 7.1 cm, and no lymph node infiltration was found in the 8 patients who received axillary lymph node dissection. Local recurrence occured in 8 patients (26%). 75% (6/8) of these patients had been treated with breast conserving surgery. In patients with the diagnosis of a malignant phyllodes tumor we observed a recurrence rate of 40% (4/10), in those with borderline tumors of 25% (2/8) whereas those with benign phylloides tumor had a local relapse rate of 8% (1/12). Distant metastases were seen in 4 patients (12%) with a malignant phyllodes tumor. All patients with distant metastases in the follow up had been treated radically (mastectomy) at primary diagnosis. Neither regarding age at primary diagnosis nor tumor size there was a significant difference between patients with local recurrence or metastatic spread and those without (p=0.284 tumor size, p=0.739 for age, Wilcoxon-W).

Conclusion: We recommend local excision with appropriate surgical margins in all patients if the tumor-to-breast ratio is sufficient for good cosmesis. Routine axillary dissection should not be recommended. This recommendation is concordant with other studies since lymph node involvement is a rare event. Patients with a malignant tumor are at higher risk for local recurrence and metastatic spread. The histopathologic classification seems to be the strongest prognostic factor in this disease.