D2I2.
benign

Fibroadenoma

Fibroadenomas are breast tumours characterized by an admixture of stromal and . Breasts are made of lobules and ducts. These are surrounded by glandular, fibrous and fatty . Fibroadenomas develop from the lobules. The glandular tissue and ducts grow over the lobule to form a solid lump.

Underlined words are explained — tap any of them.

Plain-language summary adapted from Wikipedia. Not medical advice.