Fibroadenomas A fibroadenoma is a benign lump that evolves from the fibrous tissues in the breast (stroma). They are very common, with over 10% of women having at least one fibroadenoma in their lifetime. Many women will have multiple fibroadenomas. Most fibroadenomas are diagnosed in women between 15 and 40 years of age. They are usually slow growing and painless. They tend to be firm, rubbery and smooth to touch. They often feel mobile, meaning that they move around when pressed. Being benign, they do not have the ability to ‘spread’, but they can grow from a few millimetres to over 5cm in size. Fibroadenomas are not cancerous but can be removed if they cause discomfort, are large or grow rapidly. Phyllodes tumours Phyllodes tumours are another kind of tumour of the breast. They are much less common than a fibroadenoma (about forty times less common in fact). They tend to be more common in women in their 50s and 60s but can occur at any time. Phyllodes tumours can look similar to a fibroadenoma on ultrasound and they will usually require a biopsy or even complete removal to tell them apart. Most (about two thirds) are completely benign. Some, however, have features that make them more likely to become cancerous, and very rarely, they are already identified as being malignant. The surgery for a fibroadenoma or a phyllodes tumour is generally more straight forward than surgery for breast cancer. Dr Lancashire will be able to explain more about what you can expect from surgery if that is recommended.