Outcome of Phyllodes Tumors of the Breast: A series of Consecutive cases

Background: Phyllodes tumor of the breast (PTB) is a rare tumor. PTB exist in benign (BPTB), borderline, and malignant (MPTB) subtypes. Local recurrence (LR) is the most common site of relapse. Treatment of early-stage PTB consists of local excision (LE), with free margins of resection (MR) or mastectomy (MM). Patients and Methods: We conducted a retrospective study of all consecutive patients with early-stage PTB treated with breast surgery at our institution for 8 years, in order to describe the outcome and the clinical behavior of PTB. The primary end-points of our study were disease-free survival (DFS) and overall survival (OS). Secondary endpoints were the description of the pathological features, the site of first recurrence (SFR), and prognostic factors. Results: We included a total of 16 patients. Four patients had BPTB, and 12 had MPTB. Median age was 50 years (21-81), and 62.5% was postmenopausal. Five patients (31.25%) were treated with LE and 11 (68.75%) with MM. Median tumor size was 3.6 cm (1.3-19), median mitosis/high-power field was 10 and 6.25% had positive-MR. With a median follow-up of 97 months, 5-year DFS probability was 65%. There were 5 recurrences (31.25% of all patients), all of them in the malignant subtype. 5-year OS probability was 66%. The most common SFR was LR (62.5%), followed by lung (18.75%) and bone (18.75%) metastases. In univariate analysis, T> 4.5 cm (p=0.004) and positive-MR (p=0.038) were associated with an increased risk of relapse and death. Conclusion: BPTB is associated with a good prognosis after adequate surgery. However, MPTB has a high risk of relapse and death after surgery, and this risk increases with larger tumors and positive-MR.