Some inherited genetic disorders are known to increase the risk of developing a phyllodes tumor, but in most cases, the cause is unknown. Most phyllodes tumors are benign. They may look very much like common benign breast tumors called fibroadenomas.

Are phyllodes tumors movable?

Phyllodes tumor is the most commonly occurring nonepithelial neoplasm of the breast, though it represents only about 1% of tumors in the breast. It has a smooth, sharply demarcated texture and typically is freely movable.

What does a phyllodes tumor feel like?

Phyllodes tumors grow very quickly. Breastcancer.org says that the first symptom is often a lump under your skin. The lump will feel smooth to the touch. The skin over your breast might also turn red or discolored and feel warm.