...Rui Caetano Oliveira; Fernando C. Schmitt Background: The presence of highly cellular stromal fragments in breast fine needle aspirates (FNA) suggests some classical differential diagnoses such as cellular fibroadenoma, phyllodes tumour (PT), metaplastic carcinomas, and some mesenchymal...

... of a fibroadenoma or phyllodes tumour and in whom a preoperative fine-needle aspiration was performed. The following cytological criteria were assessed: number of stromal and epithelial fragments, stromal-to-epithelial ratio, stromal cellularity, stromal borders, stromal atypia, and proportion of background wavy...