Phyllodes tumor is a nonepithelial breast tumor that may be benign or malignant.
Phyllodes tumors are frequently large (4 to 5 cm) at diagnosis. Approximately 10 to 25% are malignant (1), accounting for < 1% of breast cancers. Between 20% and 35% of these tumors recur locally, and distant metastases occur in 10 to 20% of patients.
Usual treatment of a phyllodes tumor is wide excision, but a mastectomy may be more appropriate if the mass is large or histology suggests cancer (2, 3). Radiation therapy may be recommended in some cases.
Prognosis is good unless metastases (extremely rare and usually pulmonary) are present.
References
1. Rosenberger LH, Thomas SM, Nimbkar SN, et al. Contemporary multi-institutional cohort of 550 cases of phyllodes tumors (2007-2017) demonstrates a need for more individualized margin guidelines. J Clin Oncol. 2021;39 (3):178–189. doi: 10.1200/JCO.20.02647
2. National Comprehensive Cancer Network. NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines). Breast Cancer, version 2.2026 https://www.nccn.org. Accessed May 17, 2026.
3. National Comprehensive Cancer Network. NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines). Soft Tissue Sarcoma, version 3.2026 https://www.nccn.org. Accessed May 17, 2026.
