BREAST CANCER

Cancer is a group of diseases that can appear in any part of the body and take many forms. Breast cancer is a disease in which malignant (cancerous) cells are found in breast tissues. Most cancers form initially in the terminal duct lobular units of the breast. Glandular tissue is more abundant in the upper outer portion of the breast; as a result, half of all breast cancers occur in this area. The glandular tissue consists of lobules that group together into 15-25 lobes arranged approximately in a spoke-like pattern.

Anatomy

• The mammary gland lies over the pectoralis major muscle and extends from the second to the sixth rib in the vertical plane and from the sternum to the anterior or midaxillary line.
• The mamma consists of glandular tissue arranged in multiple lobes composed of lobules connected in ducts, areolar tissue, and blood vessels.
• A network of lymphatics is formed over the entire surface of the chest, neck, and abdomen and becomes dense under the areola.
• The following lymphatic pathways originate mostly in the base of the breast: The axillary or principal pathway passes form the upper and lower halves of the breast to the chain of nodes situated between the second and third intercostal space; the transpectoral pathway passes through the pectoralis major muscle to the supraclavicular lymph nodes; and the internal mammary pathway passes through the midline, through the pectoralis major and intercostals muscles (usually close to the sternum) to the nodes of the internal mammary chain.

Natural History

• As breast cancer grows, it travels along the ducts, eventually breaking through the basement membrane of the duct to invade adjacent lobules, ducts, fascial strands, mammary fat, and skin. It then spreads through the breast lymphatics and into the peripheral lymphatics; tumor can invade blood vessels.
• About 20 to 40 percent of newly diagnosed stage T1 and T2 breast cancers, respectively, have pathologic evidence of axillary nodal metastases; the incidence is correlated with tumor size.
• Metastases to the internal mammary nodes are more frequent from inner quadrant and central lesions; they occur more often when there is axillary node involvement. Supraclavicular nodes occasionally are involved.
• Vascular invasion by tumor and hematogenous metastases to the lungs, pleura, bone, brain, eyes, liver, ovaries, and adrenal and pituitary glands occurs, even with small tumors.
• Metachronous bilateral carcinoma of the breast occurs in 5 to 8 percent of patients and is simultaneous in approximately 1 percent.

Clinical Presentation

• Patients with carcinoma in situ, T1, or T2 breast cancers present with a painless or slightly tender breast mass or have an abnormal screening mammorgram.
• Mammography used to detect about 40 to 50 percent of these lesions; about 35 percent of tumors detected by mammography and physical examination are invasive carcinomas smaller than 1 cm.

Epidemiology

• Breast cancer is one of the deadliest cancer in women in the U.S. According to the American Cancer Society (ACS), approximately 211, 300 new cases are expected to occur in the year 2003.
• The lifetime risk of any particular woman getting breast cancer is about 1 in 8.

Risk Factors

• Since there are many factors contributed to breast cancer recurrence, every women’s risk is different. Women who are childless, or had her first child at the age after 30 has increased the risk for breast cancer.
• The most important risk factor is age - woman who are older has a greater chance of getting breast cancer (having a mother, sister, or daughter with breast cancer doubles your risk).
• About 5-20 percent of women with breast cancer have several relatives who have had breast cancer and/or ovarian cancer.
• Patients with previous cancer are at a higher risk to spread to the lymph nodes and whose tumor was large in size.
• Family history of this disease.
• Having had radiation therapy to the chest region.
• Being Caucasian.
• Having your menopause late (after 50 years old).
• Getting your periods young (before your 12 years of age).
• Risk factor increases by having genetic mutation.

Symptoms

The early stages of breast cancer may not have any symptoms. It is important to follow screening recommendations by your doctor. As a tumor grows, it can produce a variety of symptoms including:

• Lump or thickening in the breast or underarm.
• Change in size or shape of the breast.
• Nipple discharge or nipple turning inward.
• Redness or scaling of the skin or nipple.
• Ridges or pitting of the breast skin.
• Diagnosis/Stages.
• The method used to detect breast cancer is a mammogram. A diagnostic mammogram is another set of x-rays; however, it is more complete with close ups on the suspicious areas.
• Ultrasound is another method, uses high-frequency sound waves to outline the suspicious areas of the breast.
• When breast cancer is suspected, a doctor will perform a biopsy. A biopsy may be performed with surgery. There are different types of biopsies; they differ on how the much tissue is removed. To performs biopsy some use a very fine needle, while others use thicker needles or even a small surgical procedure to remove more tissue. Your doctor will decide which type of biopsy is needed depending on your particular breast mass.Doctors diagnose and classify breast cancer according to stages. In order to determine the stage of breast cancer, the oncologist considers three important factors: tumor size, nodal status, and metastasis. This staging is narrow to a simple version:• Stage 0 (called carcinoma in situ)
• Lobular or ductal carcinoma in situ: Lobular carcinoma (LCIS) refers to abnormal cells lining a gland in the breast. Ductal carcinoma (DCIS) refers to abnormal cells lining a duct.
• Stage I early stage breast cancer where the tumor is less that 2 cm across and hasn't spread beyond the duct or lobule.
• Stage II - early stage breast cancer where the tumor is either less than 2 cm across and has spread to the lymph nodes under the arm; or the tumor is between 2 and 5 cm but still confined to the breast; or the tumor is larger than 5 cm and hasn't spread outside the breast
• Stage III locally advanced breast cancer where the tumor is greater than 5 cm across and has spread to the lymph nodes under the arm; or the cancer is extensive in the underarm lymph nodes; or the cancer has spread to lymph nodes near the breastbone or to other tissues near the breast.
• Stage IV metastatic breast cancer where the cancer has spread outside the breast to other organs in the body, most often the bones, lungs, liver, or brain. Depending on the stage of your cancer, your doctor may want additional tests to see if you have metastatic disease.

Treatment

Surgery is usually the first choice of treatment for breast cancer. Nearly all women with breast cancer will have some type of surgery. The surgery is to remove as much of the cancer as possible, and there are many different ways that the surgery can be carried out.

• In breast conservation therapy (BCT) surgeons perform a lumpectomy which means they remove the tumor with a little bit of breast tissue around it but do not remove the entire breast.
• In advanced-stage treatment when cancer spreads, or metastasizes, from the initial site in the breast, it often does so through the lymph system. If the lymph nodes contain cancer, she may need chemotherapy which is an aggressive treatment. To prevent cancer cells from establishing themselves elsewhere in the body, the lymph nodes that drain the breast area are often removed during surgery.
• In order to decrease a patient’s risk of recurrence, many breast cancer patients are offered chemotherapy. Chemotherapy is the use of anti-cancer drugs that go throughout the entire body.
• Radiation therapy is offered to breast cancer patients who received breast conservation therapy (BCT). Radiation therapy is offered to breast cancer patients to rid the body of any microscopic cancer cells that may remain near the area where the cancer was originally found. Your radiation oncologist can answer questions about the utility, process, and side effects of radiation therapy in your particular case.