Phyllodes tumor

  • Can be benign or malignant
  • Arises from periductal stroma
  • The papillary growth pattern is the origin of the name ‘Phyllodes’ (leaf-like in Greek)
  • Large rapidly growing without calcifications. Calcifications when present (rare) are large and chunky
  • Difficult do distinguish from a highly cellular fibroadenoma
  • The clefts in the papillary growth appear as cystic spaces on imaging
  • Cellular lesion is iso intense on T2 and rapidly enhances post contrast
  • A pre-existing fibroadenoma that rapidly enlarges (>20%  increase in diameter during 6 months) should raise suspicion of Phyllodes