Margin Management and Adjuvant Therapy for Phyllodes Tumors: Practice Patterns of the American Society of Breast Surgeons Members

Background Phyllodes tumors (PTs) are rare breast neoplasms with variable clinical behavior by histologic type: benign, borderline, or malignant. Until recently, management guidelines recommended one approach for all subtypes. Methods A 21-question survey was sent to American Society of Breast Surgeon members to evaluate management patterns by subtype. Surgeon demographics, decisions regarding management of margins, re-excision, surveillance, and synoptic reporting were collected. Chi-square or analysis of variance (ANOVA) were used as appropriate, with significance set at p < 0.05. Results A total of 493 of 2969 surveys were completed for a response rate of 18.3%. Among the survey takers, 55% were fellowship trained, 72% were in practice > 10 years, and 82% performed > 100 breast cases per year. Although 25% of respondents enucleate a mass with clinical suspicion of a PT alone, this decreased to 18% if a preoperative core biopsy performed was suggestive of PT. For margin management, 47% do not re-excise positive margins for benign PTs, but 96% would for a borderline or malignant PTs (p < 0.001). Only 2% perform axillary staging for malignant PTs, and 90% refer borderline or malignant PTs for radiation. Two-year surveillance was performed by about half of respondents for benign PT. However, two-thirds of respondents would increase surveillance to 5 years for borderline or malignant PTs. Only 38% report a templated synoptic pathology report at their institution. Conclusion PT management patterns are evolving but still variable when looking at initial margin intent, decision for re-excision, radiation referral, pathologic reporting, and surveillance. This suggests the need for more specific management guidelines by subtype given differences in clinical behavior.

Automated summary

Phyllodes tumors (PTs) are rare breast neoplasms with variable clinical behavior by histologic type. A survey of American Society of Breast Surgeon members found that management patterns for PTs are evolving but still vary, indicating the need for more specific management guidelines by subtype given differences in clinical behavior.