Today’s radiation technology present more breast cancer treatment options than ever before.
Breast Cancer Overview
Breast cancer is the second most common cancer to affect women, after skin cancer. Fortunately, early diagnosis and advances in breast cancer treatment have enhanced the chances of surviving breast cancer. It is predominantly a disease that occurs among postmenopausal women, with 70% of all cases in women older than 55 years. With the widespread use of mammography, younger women are now being diagnosed with early stage breast cancer. Approximately 227,000 women will be diagnosed with breast cancer in the United States in 2012.
Risk factors for breast cancer include family history, menstruating at an early age, taking hormones such as estrogen and progesterone, drinking alcoholic beverages and having breast tissue that is dense on a mammogram. Most breast cancer is diagnosed through a mammogram, but there are other signs such as a lump in the breast, change in size or shape, changing color or a dimple on the skin or fluid, other than breast milk, from the nipple.
Breast cancer may be broken down into two types: non-invasive and invasive tumors.
Non-invasive tumors are malignant but have not yet progressed beyond the structure from which they arise, typically the milk producing glands or ducts. These tumors are typically not palpable and are most frequently identified by routine mammography. 90% of women diagnosed with non-invasive disease are ultimately cured. The most common form of non-invasive tumor is called ductal carcinoma in situ. Invasive forms of breast cancer have spread beyond the ducts into the normal tissue of the breast. Infiltrating ductal carcinoma is by far the most common form of breast cancer, accounting for over 90% of all cases.
Breast Cancer Treatment Options
Surgery, radiation and chemotherapy are effective treatments currently used against breast cancer. Which breast cancer treatment or combination of treatments is best for you depends on the type and size of the tumor. Additional therapies such as hormone therapy and targeted therapy may be used for recurrent breast cancer and in more advanced cases of metastatic disease.
One of several different surgical procedures may be recommended depending primarily on the stage of the disease. For early stage breast cancer, a lumpectomy, involves the removal of the tumor or lump and a minimal amount of the surrounding healthy tissues that may contain cancerous cells. Some of the lymph nodes under the arm may be removed for biopsy to see if the tumor has spread. A partial mastectomy, which removes a greater portion of the breast, may be recommended for less contained yet still early stage breast cancer. Both procedures are considered breast–conserving surgery. For more advanced cases, surgeons often perform a full mastectomy to remove the entire breast as well as surrounding lymph nodes.
Chemotherapy may be used as a breast cancer treatment before or after surgery. Treatment typically lasts from three to six months. Your oncologist may recommend one of three different forms of chemotherapy. Neo-adjuvant or primary systemic chemotherapy is used before radiation or surgery to help shrink the tumor. Adjuvant chemotherapy is used after radiation or surgery to destroy any remaining cancer cells. Systemic chemotherapy circulates throughout the body via the bloodstream when the cancer is metastatic.
Estrogen is needed in two out of three women for breast tumors to continue to grow. Certain types of hormone therapy block estrogen from binding to the cancer cells and slow down their growth. Tamoxifen and toremifene bind to the estrogen receptors on the breast cancer cells so the estrogen cannot bind to them. Hormone therapy with an aromatase inhibitor such as letrozole or anastrozole is used with postmenopausal women to prevent the hormone androgen from turning into estrogen, depriving the cancer cells of an estrogen source.
Targeted therapy uses pharmaceuticals to seek and attack molecules and cellular activity that the cancer depends on to survive and grow. One out of five breast cancer patients has too much of a growth-promoting protein called HER2 on the surface of the cancer cells. Targeted therapy interferes with the protein so the cells can no longer grow and divide, slowing or stopping the cancer’s growth.
Breast Cancer Radiation Therapy
Radiation therapy is commonly used after lumpectomy, partial, or total mastectomy surgery. The purpose of the radiation treatment to the entire breast is to destroy any residual cancer cells that may remain in the breast after surgery. Use of postoperative radiation therapy reduces the risk of recurrence from 50% to 5%. Both External Beam Radiation Therapy (EBRT) where radiation is delivered from outside the body, and Internal Radiation Therapy (IRT), where the radiation is delivered via a source implanted within the body, are used as breast cancer treatments.
Breast Cancer Radiation Therapy
3D-Conformal Radiation Therapy and Intensity-Modulated Radiation Therapy (IMRT)
3D-Conformal Radiation Therapy and Intensity-Modulated Radiation Therapy (IMRT) are two forms of External Beam Radiation Therapy. During 3D-Conformal treatments, a device called a "multi-leaf collimator" will shape the individual radiation beams to “conform” to the shape of your tumor according to the data and instructions it receives from the system computer. IMRT uses thousands of radiation “beamlets” from many different angles to deliver a single dose of radiation. The intensity of the “beamlets” can change during the treatment session to modulate the dose, so that the tumor receives a very precise high dose of radiation, while minimizing damage to surrounding, normal tissue.
Before each session, a Radiation Therapist will carefully position you on the treatment table using a body immobilizer for precise body placement. Image guidance will be used to confirm the location of the tumor before the therapy begins. During your treatment sessions, the radiation delivery system will revolve around you, delivering the radiation according to the plan set by your Radiation Oncologist. Each treatment session lasts from 10 to 30 minutes. Typically, you will be scheduled for five sessions a week for five to six weeks. The sessions are pain-free and require no sedation so you can return to your normal activities right away.
Accelerated Partial Breast Irradiation (APBI)
Accelerated Partial Breast Irradiation (APBI) is almost always delivered with a specialized form of High Dose Rate Brachytherapy (internally delivered radiation therapy), but it can also by done with short-course external radiation. APBI is ideal for early stage breast cancer cases where breast preservation is a priority. In APBI Brachytherapy, your general surgeon will insert a catheter through the skin and into the cavity left by the removed tumor. Once inserted, it is left in place for the rest of the treatment course. During treatment, a computer-controlled machine inserts tiny radioactive “pellets” into the catheter to deliver the radiation directly to the tumor. APBI is an effective, post-lumpectomy radiation therapy to destroy any remaining cancer cells in the breast tissue and to help prevent a recurrence. It reduces your breast cancer treatment from six weeks to two sessions per day, six hours apart, for five days. This means much less stress on you and your family, less time away from home and work and a quick return to your normal routine. It requires no sedation so you can drive yourself back and forth to treatments.