Biopsy-excision concordance in fibroepithelial breast lesions: Predictors of phyllodes tumor

Distinguishing phyllodes tumor (PT) from fibroadenoma and other fibroepithelial lesions (FELs) on initial biopsy remains challenging. This retrospective analysis included 125 patients treated between 2008 and 2025 who had a preoperative tissue diagnosis of a fibroepithelial lesion followed by surgical excision. Final pathology demonstrated PT in 47/125 lesions (37.6%). PT was confirmed in 24/32 (75%) lesions classified as suspicious for PT, 14/46 (30.4%) indeterminate fibroepithelial/biphasic lesions, and 9/47 (19.1%) fibroadenoma-favoring lesions (P < 0.001). Patients with PT were older and had larger lesions. In multivariable analysis, suspicion for PT on initial pathology was the only variable independently associated with final PT diagnosis (adjusted OR 10.52, 95% CI 3.06-36.12; P < 0.001). Initial pathology interpretation provides clinically meaningful risk stratification and supports consideration of surgical excision when PT cannot be excluded within a clinicoradiologic-pathologic framework.