Types of Breast Cancer

The type of breast cancer you have is diagnosed based on the breast cells that are affected and the risk that the cancer will spread to another part of your breast or body.

UPMC experts provide advanced care for all types of breast cancer, including:

Noninvasive (in situ) Breast Cancer

Noninvasive breast cancer — also known as in situ breast cancer — refers to cancers that have not spread outside the area of breast tissue where they started.

Types of noninvasive breast cancers include:

• Ductal carcinoma in situ (DCIS) — DCIS is an early-stage breast cancer that develops in the lining of the milk ducts and has not spread to other parts of the body.
• Lobular carcinoma in situ (LCIS) — LCIS starts in the glands that produce milk, called the lobules, and has not spread to other parts of the body. Although not technically considered cancer, LCIS increases your risk of developing breast cancer in the future.

Invasive Breast Cancer

Invasive breast cancers spread outside the milk ducts or lobules to other parts of the breast or body.

Types of invasive breast cancers include:

• Invasive ductal carcinoma — The most common type of breast cancer, invasive ductal carcinoma, accounts for 70% to 80% of breast cancer cases in women and 90% in men. This type of breast cancer starts in the lining of the milk ducts and may be preceded by ductal carcinoma in situ.
• Invasive lobular carcinoma — As the second most common type of breast cancer, invasive lobular carcinoma accounts for 10% of breast cancer cases in women. It begins in the glands that produce milk.
• Inflammatory breast cancer — Inflammatory breast cancer is a rare, aggressive type of breast cancer that accounts for 1% to 5% of breast cancer cases in women and almost none in men. Instead of causing a lump, it causes reddening and swelling of the breast. As a result, it can sometimes be mistaken for infections called mastitis or cellulitis.
• Paget’s disease of the nipple — A rare condition that accounts for 1% of breast cancer cases, Paget’s disease of the nipple causes redness and irritation of the nipple on one breast. It can be mistaken for eczema or an infection.
• Triple-negative breast cancer — Triple-negative breast cancer is aggressive and occurs in 15% of breast cancer cases. Because the cancer cells don’t have hormone receptors or HER2 proteins, triple-negative breast cancer can be challenging to treat.
• Angiosarcoma — Angiosarcoma makes up less than 1% of breast cancers and starts in the cells that line the blood or lymph vessels.
• Phyllodes tumor — A phyllodes tumor is a rare tumor that develops in the connective tissue of the breast. Although most phyllodes tumors are benign (noncancerous), some can be malignant (cancerous).

Why Choose UPMC for Breast Cancer Care?

When you choose UPMC for breast cancer care, you will receive:

• Comprehensive breast cancer expertise — The breast cancer experts at UPMC provide state-of-the-art care for every form of breast cancer at every stage of the disease.
• Personalized, collaborative care — Our surgical, medical, and radiation oncologists work together to plan the best course of therapy for you.
• Supportive services tailored to your needs — Our approach to breast cancer care honors your preferences by blending advanced clinical methods with supportive services for the best possible results.

By UPMC Editorial Staff. Last reviewed on 2025-09-18.