A member of the Seattle Cancer Care Alliance Network

Breast Cancer Treatment

Breast cancer treatment depends on the type and the stage of cancer.

Surgery, radiation, and chemotherapy drugs are the three most common cancer treatments for breast cancer. For some patients, certain hormones are given to keep the cancer cells from developing.

At Kaiser Permanente, we keep up with the rapid changes and improvements in cancer treatment. We offer chemotherapy that's easier to tolerate, radiation targeted to the cancer growth, and surgery that is less invasive. We consistently review the latest research findings to make sure our treatments are the most effective.


Sometimes surgery is all that's needed to remove cancer cells from the breast and surrounding tissue. The most common types of breast cancer surgery are lumpectomy and mastectomy.

  • A lumpectomy removes just the tumor and a small amount of normal tissue around it.
  • A mastectomy typically removes more of the breast tissue, but only as much as is needed.

Patients might go home the day of the surgery or spend a day or two in the hospital, depending on the extent of the procedure.

Radiation and Chemotherapy

Some breast cancer patients have radiation or chemotherapy, or both after surgery. Others may have radiation or chemotherapy before surgery to shrink the tumor. That helps surgeons remove less of the breast during a lumpectomy or avoid a mastectomy.

Treatment sessions for chemotherapy or radiation can be as often as a couple of times a week or just once every few weeks. There might also be a few weeks of rest between treatments.

Hormone Blocking Therapy

Some breast cancers are called "hormone receptor-positive" because they need the hormone estrogen or progesterone to continue growing. These types of cancers produce estrogen (ER+) or progesterone receptors (PR+), or both on their surface. 

Certain drugs such as tamoxifen (Nolvadex) work to stop these hormones. If you have a hormone receptor-positive cancer you will likely take a drug to decrease the chance of your cancer returning or growing. Your doctor will let you know your tumor test results and discuss if you require one of these drugs.

Targeted Therapies

Targeted cancer therapies are drugs or other substances that block the growth and spread of cancer. They interfere with specific molecules involved in tumor growth and progression. (Tamoxifen is one type of targeted therapy.)

The molecules to be targeted are identified on the biopsy specimens collected during the diagnosis phase.

New targeted therapies are being developed all the time. Your cancer care physician is your best source of information on whether you are a candidate for these types of therapies.

Reactions to Therapy

Your doctor, nurse, nutritionist, and oncology pharmacist can help you manage any side effects that might arise.

Common side effects from radiation or chemotherapy include nausea, vomiting, fatigue, pain, problems thinking clearly, skin sensitivity, and hair loss. People might have a higher risk of getting an infection because blood counts (number of red and white blood cells and platelets) can temporarily drop.

Side effects depend on the dose and type of drug or treatment. You won’t be sure how you’ll respond — or if you’ll have any side effects — until you begin treatment.

Side or after effects from surgery depend on the extent of the operation. After breast surgery, people might feel some pain down the arm, stiffness in the shoulder and arm, and perhaps some loss of feeling.

Lymphedema: Patients who've had surgery or radiation therapy that involved their lymph nodes can develop a condition called lymphedema. The lymph nodes and lymph system drain fluid from the tissues and move it throughout the body. If surgery or radiation treatment interrupts the process, fluid can build up in the arm or hand causing painful swelling.

Lymphedema can happen any time after surgery or radiation. But it usually develops slowly. Many people don't notice it for months or even years after cancer treatment has ended.

Lymphedema can be managed through good home care which includes exercise, massage, and wearing a compression bandage. It's important to treat lymphedema early. Call your doctor right away if you notice any swelling in your arm or hand.

Contacting Your Care Team at Kaiser Permanente

As you discuss your treatment and possible side effects with your care team, also talk about what signs and symptoms require medical attention right away. When you experience those symptoms, you should call your care team for help or advice. After clinic hours, you should call our Consulting Nurse Service for help, available 24 hours a day, 7 days a week.

Taking Care of Yourself

It might seem like your life is revolving around cancer treatment during this time. But it’s important to take care of your other physical needs and your emotional needs as well.