Is There an MRI Characteristic Feature That Distinguishes a Phyllloid Tumor From a Fibroadenoma

Abstract

Aim: Cellular fibroadenomas (CFAs) and phyllodes tumours (PTs) arise from the breast parenchyma and consist of both epithelial and stromal components. In our study, we aimed to investigate and compare magnetic resonance imaging (MRI) characteristics of these lesions to facilitate the process of differentiation and management. Materials and Methods: We retrospectively analysed the breast MRI data of patients pathologically diagnosed with PT and CFA. 25 patients with preoperative MRI who were diagnosed with PT in the last five years and 25 patients with preoperative MRI who were diagnosed with CFA in the last one year were randomly selected and included in the study. MRI findings were classified according to the Breast Imaging Reporting and Database System (BIRADS). Pearson Chi-Square and Fisher's Exact tests were used to calculate the statistical difference between MRI features of CFA and PT. Results: The mean age was calculated 32.68 +/- 7.73 for patients with CFA and 38.32 +/- 10.71 for patients with PT (p=0.038). In fat suppressed T2 weighed imaging (WI) both lesion groups showed similar characteristics; 24 of the CFAs and 19 of the PTs demonstrated an increase in signal intensity. Two CFAs and nine PTs had cystic components (p=0.017). Signal increase in the surrounding tissue in fat suppressed T2WI was seen in 11 (44%) of the PTs, but in only 1 (4%) of the CFAs (p=0.001). On delayed phase T1WI, 10 of the CFAs and 18 of the PTs sustained heterogeneous enhancement characteristics (p=0.023). Discussion: All in all, we found that PTs arise later in life compared to CFAs. Increased signal intensity in the surrounding tissue in fat suppressed T2WI and the presence of a cystic component is more suggestive of PT. In delayed phase T1WI, CFAs appear to be homogenously enhanced, whereas PTs maintain their heterogeneous enhancement.