Breast cancers can vary in how they grow and spread. The type of breast cancer you have determines what treatment you need.
Invasive ductal carcinoma (IDC): This type of breast cancer starts in the milk ducts or the surrounding tissue. It’s the most common type of breast cancer.
Other types include Paget’s disease, inflammatory breast cancer, cribriform carcinoma and medullary carcinoma—a soft tumor that looks like a part of your brain. This type of cancer has a lower chance of metastasizing to other areas of the body.
Symptoms
HER2+ breast cancers are tumors with high levels of a molecule called HER2. Cancers with this characteristic grow more quickly and have a higher risk of returning (recurring). Most people with HER2-positive breast cancer will receive chemotherapy drugs plus a drug that blocks the effects of HER2. This type of treatment reduces the chance that the cancer will grow or return.
If you have HER2-positive breast cancer, it’s important to visit a cancer center that often sees this type of cancer to get the best care. This helps us ensure your diagnosis and treatment plan is as accurate as possible.
Your doctor may suspect you have HER2-positive breast cancer if you have the following symptoms: A lump larger than your normal breast tissue—swelling in your armpit or under your collarbone, especially if it’s painful. A node that feels hard or has a different texture than the rest of your breast. Pain or tenderness in your breast, although lumps don’t usually hurt. Unusual nipple discharge, which may be clear or bloody. It can also feel like thick, wet underwear under your bra or in the fold of your skin. The area where the cancer is in your breast can change shape, and the nipple can start to look flat.
Diagnosis
Women who notice a lump in their breasts should immediately consult their doctor. Most of the time, these lumps are not cancer, but other conditions, such as fibroadenoma or a cyst, may cause them. If they are a sign of cancer, a physician will do a physical examination to determine what the lump is and whether it moves easily.
The tumor cells will then be tested to see if they have HER2. This test is done by placing the tissue under a microscope and looking for the HER2 protein. Tumors with too much HER2 grow faster and are more likely to recur. The HER2 status is also important in deciding which medications are most suitable for treatment.
HER2-positive breast cancers respond best to drugs that target the HER2 receptor, such as trastuzumab (Herceptin) and pertuzumab (Perjeta). They also tend to grow slower than other kinds of breast cancer.
Other types of treatments include surgery, which can involve the removal of part of the breast (lumpectomy) or the entire breast (mastectomy). Radiation therapy uses X-rays to kill cancer cells that remain after the other treatments. And chemotherapy uses oral or IV drugs to attack cancer cells that remain after the other treatments. The doctors at OHSU will discuss these options with you and choose the most appropriate for your situation.
Treatment
Although the disease is frequently aggressive in HER2-positive breast cancer patients, numerous treatments are available. Surgery, chemotherapy, and medications used in targeted therapy are the primary therapeutic choices. It would help if you talked to your doctor about these possibilities.
A protein called HER2 (human epidermal growth factor receptor 2) instructs breast cells when to develop and stop. The HER2 gene can occasionally mutate or acquire extra copies, which causes the tumor to spread more quickly than it should. HER2-positive breast tumors make up about 20% of cases. Breast tumors with HER2 mutations have a higher propensity to metastasize to the bones and the brain. HER2 can also be present in ovarian, bladder, and gastrointestinal malignancies. This test checks the genetics of your HER2 and finds out if you have extra copies of the gene, known as HER2 amplification.
Most people with HER2-positive breast cancer will be treated with trastuzumab or Herceptin. It is usually given with chemotherapy, such as paclitaxel and carboplatin, before or after surgery. The duration of treatment with trastuzumab is under study, but one year is effective.
Prevention
The cause of breast cancer is not fully understood, but factors such as family history and age play a role. Older women have a greater risk of developing breast cancer than younger women.
The most common symptom is a lump in the breast. These lumps may feel different than the surrounding tissue or hard to the touch. They can also be painful. Breast self-exams and regular mammograms are important to help find cancer early before it spreads.
If a tumor is HER2-positive, it means the cancer cells have too much of a protein called HER2. Normally this protein helps breast cells grow and divide. But in HER2-positive breast cancers, the HER2 gene makes too much of this protein, and it causes the tumor to grow faster. HER2-positive breast cancers were once associated with poorer outcomes, including a higher chance of recurrence and death, but treatments that target HER2 have improved the survival of these patients.
Many women with HER2-positive breast cancer get chemotherapy before surgery (neoadjuvant therapy) and medication targeting HER2 (herceptin or trastuzumab). They also get other types of treatment after surgery to destroy any remaining cancer cells. Talk with your doctor at OHSU about the best treatment options for you.