11. Types of Breast Cancer

TYPES OF BREAST CANCER:

Making an accurate diagnosis of breast cancer is difficult. The pathologist needs to identify the tissue, the type of cells present in the biopsy, and the possibility of the tumor becoming invasive breast cancer. It is very important, therefore, that an experienced pathologist examines the biopsy slides. You might want to have your slides examined by a second pathologist, one who is very experienced in studying breast tumors. This is common practice today and physicians are rarely offended when patients request a second opinion. The precise diagnosis will help your doctor decide on the appropriate treatment. The possibilities of treatment vary widely from closely watching the suspicious area, to surgery to remove only the affected tissue followed by radiation therapy, to surgery to remove one or both breasts.

You must be aware that many insurance companies are not paying for second opinions. This might be an out-of-pocket expense.

NON-INVASIVE CANCERS:

Some growths may be invasive cancer; others are noninvasive cancer. Diagnosed very early, noninvasive cancer (also called carcinoma in situ, LCIS or DCIS) has not spread beyond the duct or the lobule of the breast - not to the lymph nodes in the armpit, or to other parts of the body. Often these cancers are microscopic. Today 15 to 20% of breast cancers fall into this category.

Invasive cancer spreads to surrounding tissue in the breast and may spread to the lymph nodes in the armpit or to other parts of the body. All breast cancers, except in situ cancer, are invasive.

Treatment options are varied for women with noninvasive cancers. Usually found by mammography, noninvasive growths are very curable. Noninvasive cancer places the woman at a higher risk for developing invasive breast cancer in the future. A mastectomy or lumpectomy is the primary treatment for noninvasive breast cancer. Some women may require radiation treatments to the breast, after surgery. Tamoxifen may also be indicated to reduce the risk of developing invasive breast cancer in the future. Some women participate in clinical trials. Occasionally, they elect not only to have a mastectomy (breast removal) on the affected side, but also a prophylactic mastectomy on the opposite side to significantly reduce the chance of developing invasive breast cancer in the unaffected breast. In most cases, removal of the underarm lymph nodes is not necessary for noninvasive breast cancer

Ductal Carcinoma In Situ: (DCIS – sometimes called intraductal carcinoma) is the most common type of noninvasive breast cancer, which means that abnormal cells are found only in the lining of a milk duct of the breast. The cancer has not spread outside the duct or beyond the breast, to the lymph nodes under the arm, or to other parts of the body. A diagnosis of DCIS does place women at a higher risk of developing invasive breast cancer in the future. There are several types of DCIS. If not surgically removed, some types may change over time and become invasive cancers. Ninety-eight percent of women diagnosed at this early stage of breast cancer can be cured. The best way to find DCIS is with a mammogram. With more women getting mammograms each year, a diagnosis of DCIS is becoming more common.

Lobular Carcinoma In Situ: (LCIS – sometimes call lobular neoplasia) is a noninvasive growth limited to the lining of a milk lobule. It is a warning sign of increased risk of developing invasive cancer. Technically, it is a Stage O breast cancer. Lobular changes are also more likely to be bilateral (in both breasts). Lobular carcinoma in situ is sometimes found when a biopsy is done for another lump or unusual change that is found on a mammogram. Patients with lobular carcinoma in situ may be eligible to enroll in clinical trials for cancer prevention.

INVASIVE CANCERS:

Understanding some of the key words used to describe different types of breast cancer is important because these types vary in their prognosis (possible outlook for survival or cure), and their treatment options. An alphabetical list of terms, including the most common types of invasive breast cancer, is given below.

Adenocarcinoma: This general type of cancer starts in glandular tissue anywhere in the body. It is a descriptive term for cellular changes observed under the microscope. Adenocarcinoma may start in the breast, lung, prostate, bowel, or other organs. The biologic behavior of the adenocarcinoma depends upon its organ of origin.

Infiltrating or invasive ductal carcinoma: Infiltrating ductal carcinoma accounts for about 60-70% of breast cancers. This cancer originates in the milk passage or duct of the breast, breaks through the wall of the duct, and invades the fatty tissue of the breast. It has the potential to metastasize, or spread, to other parts of the body through the lymphatic system and bloodstream.

Infiltrating (or invasive) lobular carcinoma: This is the second most common subtype of breast cancer. Similar to invasive ductal carcinoma, this cancer has the potential to spread (metastasize) to other parts of the body. It starts in the milk-producing glands. About 10% to 15% of invasive breast cancers are invasive lobular carcinomas.

Inflammatory Breast Cancer: Inflammatory breast cancer is aggressive and fast growing. Fortunately, it is rare, occurring in only 1% of all breast cancers. This cancer makes the skin of the breast look red and feel warm, as if it were infected or inflamed. The skin may have a thick, pitted appearance. Sometimes the breast develops ridges, welts, or hives. The skin may look wrinkled. It sometimes is misdiagnosed as a simple infection. The red swollen tender skin is caused by cancer cells spreading to and blocking lymph vessels of the skin.

Metastatic Breast Cancer: When breast cancer spreads outside the breast, cancer cells can be found in the lymph nodes above the collar bone or the neck, the bones, liver, lungs, or brain. When breast cancer spreads, it is called metastatic breast cancer, even though it is found in another part of the body.

Medullary carcinoma: This cancer is somewhat less aggressive, and the prognosis (outlook) for medullary cancer is better. It has a relatively well-defined, distinct boundary between tumor tissue and normal tissue. It accounts for about 5% of breast cancers

Mucinous carcinoma: The prognosis for mucinous carcinoma is better than for the more common types of invasive breast cancer. This rare type of invasive breast cancer is formed by mucus-producing cancer cells.

Paget’s disease of the nipple: This rare type of breast cancer starts in the breast ducts. As it spreads to the skin of the nipple and the areola (the dark circle around the nipple), the area often appears crusted, scaly, and red. Bleeding, oozing, burning, or itching might be evident. Paget’s disease may be associated with infiltrating breast carcinoma or in situ carcinoma.

Phyllodes tumor: Many types of breast cancer start in the ducts or lobules of the breast. This very rare type of breast tumor forms from the stroma (“the cement that holds the mild producing breast tissue together”) of the breast. Phyllodes (also spelled phylloides) tumors are usually benign. Less than ten women per year die of malignant Phyllodes tumors. These cancers are treated with surgery. They do not respond to hormonal therapy and are less likely than most to respond to chemo or radiation therapy.

Recurrent Breast Cancers: Even when a tumor in the breast seems to have been completely removed or destroyed, the disease sometimes returns because undetected cancer cells remained somewhere in the body after treatment. As many as 25 to 33 percent of women diagnosed with operable breast cancer will have a recurrence within five years of diagnosis. Most appear within the first two or three years after treatment, but breast cancer can recur years later. It may come back in the breast, in the soft tissues of the chest (the chest wall), in the opposite breast, or in another part of the body. Cancer that returns only in the area of the surgery is called a local recurrence. If the disease returns in another part of the body, the distant recurrence is called metastatic breast cancer.

Tubular carcinoma: Tubular carcinomas are a special type of infiltrating breast cancer. They account for about 2% of all breast cancers. The prognosis for tubular carcinoma is better than for infiltrating ductal or lobular carcinomas.