Phyllodes Tumors—The Predictors and Detection of Recurrence

Phyllodes tumors are rare breast neoplasms and the histopathological grade and surgical margins help guide treatment and follow-up. The traditional surgical teaching is resection with ≥10 mm margins, but are narrower surgical margins acceptable? The purpose of our study was to identify predictors of local recurrence.A retrospective analysis was performed to identify patients with phyllodes tumors who underwent surgery between 2002 and 2014 using a regional pathology database. Electronic medical records were used to identify surgical management, pathological characteristics, and follow-up encounters.A total of 150 phyllodes tumors were included: 110 of 150 (73%) benign, 21 of 150 (14%) borderline, and 19 of 150 (13%) malignant. At initial surgery, 29 specimens had a positive margin and 15 (56%) underwent re-excision. Seventy tumors had a surgical margin of ≤1 mm, 40 had a margin of 2 to 9 mm, and 11 had a margin of ≥10 mm. There were 11 of 150 (7.3%) locally recurrent tumors: 5 of 11 (45%) benign, 3 of 11 (27%) borderline, and 3 of 11 (27%) malignant. In total, 10 of 11 locally recurrent tumors had a positive margin or ≤1 mm margin at initial surgery.Phyllodes tumors can have a personalized treatment approach based on histopathological grade and surgical margins. Borderline and malignant phyllodes tumors with a positive or ≤1 mm surgical margin have an increased risk of recurrence. In benign phyllodes tumors, an optimal narrow negative margin may exist but the traditional ≥10 mm excisional margin is not necessary. Local recurrence rates may be sufficiently low in benign phyllodes tumors that imaging can be performed on the presence of clinical symptoms.