A Pre-operative Score to Discriminate Fibroepithelial Lesions of the Breast: Phyllode Tumor or Fibroadenoma?

Background/Aim: Fibroepithelial lesions (FEL) of the breast include fibroadenomas and phyllodes tumors (PT). Their histologic characteristics on core needle biopsy can overlap, while their clinical management is different. The aim of this study was to develop and to validate a pre-operative score for the diagnosis of PT with surgical decision rules. Patients and Methods: We developed a pre-operative score for the diagnosis of PT by performing logistic regression on 217 FEL of the Rene Huguenin Hospital. This score and the surgical decision rules were validated on 87 FEL of the Lariboisiere Hospital. Results: Three variables were independently and significantly associated with PT: age >= 40 years, mammography's tumor size >= 3 cm and PT diagnosed by CNB. The pre-operative score was based on these three criteria with values ranging from 0 to 10. Surgical decision rules were created: the low-risk group of PT (score <= 2) had a sensitivity of 92.6% and a LR- of 0.2, the high-risk group (score>7) had a specificity of 93.5% and a LR+ of 4.4. In the validation sample, surgical decision rules were applied. Conclusion: These surgical decision rules may prove useful in deciding which FEL needs surgical resection.