Diseases & Conditions

Beating breast cancer and other benign breast conditions is about knowledge, and the earlier you learn what you’re dealing with, the better. At Fountain Valley Regional Hospital and Medical Center, we focus on knowing about all breast diseases and conditions — and sharing that information with you. The following information describes various breast diseases and the symptoms and characteristics that may accompany them.


Adenosis is a condition in which the breast lobules are enlarged and contain more lobules than normal. This condition is normally found in women with fibrocystic changes.


Angiosarcoma is a rare form of malignant cancer that affects the linings of the blood vessel walls. This type of cancer can occur anywhere in the body and can be very aggressive.

Duct ectasia

Duct ectasia is also referred to as mammary duct ectasia and occurs when a milk duct beneath a nipple becomes dilated. As a result, the duct walls fill with a thick, sticky substance and become blocked.

Ductal or lobular hyperplasia

Hyperplasia is an overgrowth of cells that line the ducts or lobules. Based on their appearance under a microscope, hyperplasia is considered to be ductal or lobular.

Ductal carcinoma in situ

Ductal carcinoma in situ is a type of noninvasive breast cancer. The cancer begins in the milk ducts and does not invade any of the surrounding tissues.

Fat necrosis and oil cysts

Fat necrosis is what occurs when an area of fatty breast tissue is damaged, usually because of radiation or surgery. In some cases, fat cells respond differently to injury and form a sac-like collection of fluid called an oil cyst.


Fibroadenomas are solid, benign tumors of the breast that most frequently occur in adolescents, as well as in women under the age of 30. They are typically painless and can shrink in size on their own.

Fibrosis and simple cysts

Fibrosis and simple cysts are benign lumps or growths. Simple cysts are fluid-filled sacs that can vary in size, and fibrosis cysts refer to the buildup of larger amounts of fibrosis tissue.

Granular cell tumors

Granular cell tumors are early nerve cells; normally, these tumors are benign. They commonly occur in the mouth and on the skin and are rarely found on the breast.

Inflammatory breast cancer

Inflammatory breast cancer is a rare and aggressive form of breast cancer. It occurs when cancer cells block lymph vessels, which results in the skin looking very swollen or inflamed.

Intraductal papillomas

Intraductal papillomas are small, benign tumors that occur in the milk glands of the breast. These tumors are composed of gland, blood vessels and fibrous tissues.

Invasive ductal carcinoma

Invasive ductal carcinoma is the most common type of breast cancer. It occurs when abnormal cancer cells form in the milk ducts and spread to other parts of the breast tissue.

Invasive lobular carcinoma

Invasive lobular carcinoma is a type of breast cancer that begins in the milk producing glands known as lobules. This type of breast cancer is an invasive cancer and has the potential to spread to other breast tissues.

Lobular carcinoma in situ (LCIS)

Lobular carcinoma in situ (or LCIS) is a rare condition that occurs when abnormal cells form in the milk glands or lobules of the breast. LCIS can be an indicator that a woman is more prone to developing breast cancer.


Mastitis is an infection of the breast tissue. It usually results in pain, swelling, redness and warmth of the breast.

Paget disease of the nipple

Pagnet disease of the nipple is a rare form of breast cancer. It occurs when cancer cells form around the nipple. The vast majority of people with this condition also suffer from another form of breast cancer.

Phyllodes tumors

Phyllodes tumors are typically benign tumors (nearly 90 percent are non-cancerous). Phyllodes tumors are smooth lumps beneath the skin that may be warm to the touch and fast growing.

Let Fountain Valley connect you with a physician

Call ​(855) 226-3744 or use our Find A Physician tool to be connected to a breast care specialist who can help you. You can also read more about breast diseases and conditions in our Health Library.