Most of the early effects of breast cancer involve changes to the breast, such as a lump or thickening of breast tissue, discolored or pitted skin on the breast, or discharge (other than milk) from the nipple.

Breast cancer refers to cancer that begins in the cells within the breasts. It can metastasize (spread) from the breasts to other areas of the body, such as the bones and liver.

At first, breast cancer typically affects the breast area only. You may notice changes in your breasts themselves, when looking in a mirror or during a self-exam.

Your doctor may also detect breast cancer tumors on a screening mammogram before you notice symptoms.

As a rule of thumb, always see a doctor if you notice any changes to your breasts. The earlier breast cancer is detected, the less opportunity it has to spread and the better your outcome may be.

Read on to learn how breast cancer affects your body and symptoms you may notice.

Effects if breast cancer on the bodyShare on Pinterest
Medical Illustration by Bailey Mariner

The first effects of breast cancer involve the breasts, and symptoms will usually appear in one breast only.

Mass or lump

According to the American Cancer Society (ACS), the most common sign of breast cancer is a newly formed mass or lump in your breast.

A breast cancer mass or lump is usually irregularly shaped and painless. However, some cancerous masses can be painful and round in shape.

This is why it’s important that you see a doctor if you notice any lump or mass in your breast. They can determine if the lump is cancerous or noncancerous.

Tissue thickening

Inflammatory breast cancer, which accounts for about 1-5% of all breast cancers diagnosed in the United States, per the ACS, is most known for its effect on the skin. It can cause swelling, redness, or thickening of the skin on your breast.

Invasive ductal carcinoma is the most common type of breast cancer, making up about 75% of all breast cancer diagnoses, per This type of breast cancer, which forms inside the milk ducts (the glands that produce milk), can cause swelling and thickening of the breast skin, or changes in the skin’s texture.

Invasive lobular carcinoma is the second most common form of breast cancer, occurring in 5–15% of all invasive breast cancers, according to a 2023 research review article. It can cause a thickening or hardening of certain areas of the breast, or a change in skin texture or appearance, such as dimpling.

Changes in color and swelling

Breast cancer may cause your breasts to change color or size. They may be red or swollen.

While breast cancers themselves aren’t usually painful, the resulting swelling can cause breast pain. In certain cases, cancer lumps by themselves may be painful.

Discharge from your nipples

With breast cancer, your nipples may also undergo some noticeable changes. You might see some clear discharge come out of your nipples, even though you’re not currently breastfeeding. Sometimes the discharge also has a small amount of blood in it.

The nipples themselves can also turn inward; this is called “nipple retraction.”

Changes to the skin surrounding your breasts

The skin surrounding your breasts can also be affected by breast cancer. It may be extremely itchy and can become dry and cracked. Some women also experience dimpling of the skin along their breasts that looks like dimples of an orange peel.

In the later stages of breast cancer, tumors typically spread to your lymph nodes. The lymph nodes closest to your breast (in your underarms) are usually the first affected areas. You may feel tenderness and swelling under your arms.

Other lymph nodes can become affected because of the lymphatic system. While this system is usually responsible for transmitting healthy lymph (fluid) throughout the body, it can also spread cancerous cells that have broken off cancer tumors.

These cancerous cells may spread through the lymphatic system to the lungs and liver. If your lungs are affected, you might experience:

  • chronic cough
  • shortness of breath
  • other breathing difficulties

If cancer reaches your liver, you may experience:

  • jaundice
  • severe abdominal bloating
  • edema (fluid retention)

It’s also possible for breast cancer to spread to your bones. This is called bone metastasis.

You may have pain in these areas as well as restricted movement. Such effects can also increase your risk of injuries due to a lack of mobility. Bone fractures are a risk, too.

Breast cancer can also spread to your brain. This can result in various neurological effects, including:

  • blurry or double vision
  • confusion
  • headache
  • memory loss
  • mobility issues
  • speech difficulties
  • seizures

Breast cancer may also affect your energy levels and appetite. This may be caused by the cancer itself or the treatment you’re receiving.

You may experience:

  • excessive fatigue
  • weakness
  • appetite loss
  • unintentional weight loss

Like other cancers, breast cancer is broken down into stages. Stage 0 is the earliest stage with the fewest noticeable symptoms. Stage 4 indicates the cancer has spread to other parts of the body.

The effects of breast cancer in its early stages can depend on the exact type of breast cancer you have but are typically limited to the breast.

In later stages, if breast cancer has spread to other parts of the body, it may cause symptoms in those particular areas. Common areas cancer can spread to include the liver, lungs, bones, and brain.

Keeping up with recommended breast screenings is the best way to catch breast cancer early. Imaging tests can detect breast cancer before you even have any symptoms.

Here are breast cancer screening recommendations from the American Cancer Society.

As with other types of cancer, early detection of breast cancer greatly improves treatment outcomes.