Malignant tumours of the breast
Malignant tumours of the breast are cancerous growths that have the potential to spread (metastasize) to other parts of the body.
The most common type of malignant breast tumour is adenocarcinoma. Nearly all breast cancers start in the glandular tissue in the breast, in either the milk ducts or the milk glands. Most adenocarcinomas occur in the upper, outer part of the breast.
There are 2 main types of adenocarcinoma:
- ductal carcinoma – begins in the lining of the milk ducts of the breast
- lobular carcinoma – begins in the milk glands (lobules) of the breast
Ductal carcinoma and lobular carcinoma are also classified according to whether they are:
- non-invasive (in situ) – These cancers are confined to (have not spread beyond) their original site and have not invaded surrounding tissues.
- invasive (infiltrative) – These cancers have spread beyond their original site into surrounding tissues.
Other types of malignant breast tumours
There are other less common types of malignant breast tumours:
- inflammatory breast cancer
- Paget disease of the nipple
- triple negative and basal-like breast cancers
- rare malignant tumours
- non-Hodgkin lymphoma
- dermatofibrosarcoma protuberans
- adenoid cystic carcinoma
- carcinosarcoma (metaplastic carcinoma)
- adenosquamous carcinoma
- malignant phylloides tumour