Histologic features predict local recurrence after breast conserving therapy of phyllodes tumors.

Abstract

Pathologists can distinguish benign phyllodes tumors, which very rarely metastasize, from malignant phyllodes tumors, which metastasize in approximately one fourth of patients. However, whether these same histologic criteria can be used to predict the likelihood that a phyllodes tumor will locally recur after breast conserving therapy remains controversial. Since few patients with malignant phyllodes tumors have been treated with breast conserving surgery in any individual series, the literature was reviewed using a Medline search. After local excision, 21% (111/540), 46% (18/39), and 65% (26/40) of patients with benign, borderline, and malignant phyllodes tumors, respectively, recurred in the breast. Following wide local excision, 8% (17/212), 29% (20/68), and 36% (16/45) of patients with benign, borderline, and malignant phyllodes tumors recurred in the breast. Malignant phyllodes tumors are much more likely than benign phyllodes tumors to recur in the breast after breast conserving surgery. This high rate of local recurrence of borderline and malignant phyllodes tumors suggests that wide local excision is less than optimal therapy, and challenges us to look for methods to improve local tumor control.