lumps, and it is often bilateral. Women diagnosed with invasive lobular carcinoma may experience a firmness or unusual fullness of the breast. Lobular carcinoma in-situ differs from the other types of cancers in that it is not, in fact, a cancer. Although there is a presence of abnormal cells in the lobules of the breast, they are noncancerous. Receiving a diagnosis of lobular carcinoma in-situ is certainly better than other types of breast cancers. Although lobular carcinoma in-situ is noncancerous, it does indicate a considerably higher risk for the patient to develop another type of breast cancer. Although these are the two principal categories of origination for breast cancers, there are rare occurrences in which the cancer originates from areas other than the milk ducts and lobules.
Medullary breast cancer demonstrates lymphatic infiltrate on histology and has good prognosis. Comedocarcinoma is a subtype of DCIS that involves ductal caseous necrosis. Lymphatic dermal invasive by breast carcinoma is known as inflammatory breast cancer. This type of breast cancer is characterized by the skin turning into a texture that resembles an orange peel (and is commonly termed peau d’orange). The survival rate for this type of cancer at five years is approximately 50%. Paget’s disease of the breast presents with eczematous patches on the nipple and is a sign for an underlying carcinoma.
Other Major Pathologies of the Breast
One common abnormality of the breast found in both men and women is polythelia, also known as supernumerary nipple. Polythelia is characterized by the presence of more than the normal number of two nipples. Although supernumerary nipples can be found anywhere on the body, they are most often found on the milk line, which extends from the armpit to the groin. Although not harmful, supernumerary nipples are often removed by excision because they can develop the same diseases as normal nipples.
Another common pathology of the breast is sclerosing adenosis. Sclerosis refers to a condition where the tissues in the breast harden, leading to sclerosing adenosis as well as complex sclerosing lesions or radial scars. This disease is characterized by the presence of additional tissue in the breast lobules, which can cause lumps and discomfort. Although these lumps are noncancerous, the pain associated with it sometimes gives reason for the lumps to be removed. Sclerosing adenosis is more commonly seen in women in their thirties and forties, and occur naturally as a woman ages. Although some women do experience pain that may lead to the excision of the lump, many others experience no symptoms and their condition can go unnoticed. Due to how the disease manifests itself, however, once a lump is found, most times physicians opt to obtain a biopsy of the lump to check for cancerous tumors, which are similar to the lumps of sclerosing adenosis. Complex sclerosing adenosis and radial scars are both similar to sclerosing adenosis in that they are characterized by hardening of breast tissue, and are found primarily in older women. They differ from one another only on the account of size: any lump smaller than 1 centimeter is classified as a radial scar and lumps bigger than 1 centimeter are classified as complex sclerosing lesions.
A third relatively common pathology of the breast is fibrocystic disease. Fibrocystic breasts are characterized as breasts that contain tissue that is said to be lumpy, causing unevenness of the breast and discomfort or pain. The lumpiness in the breasts is caused by noncancerous masses within the breasts, which may be cysts or masses of hardened tissue. Classically, fibrocystic disease presents with premenstrual breast pain involving multiple lesions in both breasts. These lesions also fluctuate in size. Fibrocystic breasts are common in women, especially before menstruation or during later years in a woman’s life, however it generally declines after a woman experiences menopause. Today, physicians are leaning away from considering fibrocystic breasts as a disease due to the fact that over half of women in the United States are affected by it. In addition, the masses do not indicate an increased risk of carcinoma. Histologic types include fibrosis (hyperplasia of the breast stroma), cystic (fluid filled with ductal dilation), sclerosing adenosis (increased acini with intralobular fibrosis), and epithelial hyperplasia (increased number of epithelial cell layers in the terminal duct lobule; this type, which presents in women over 30 years of age, presents with increased risk of carcinoma if atypical cells are present).
Some benign breast tumors include fibroadenoma, intraductal papilloma, and phyllodes tumor. Fibroadenoma is a small, mobile, firm mass that occurs in patients less than 25 years of age. Fibroadenomas increase in size and tenderness with increased estrogen (such as during menstruation or pregnancy). This type of mass is not a precursor to cancer. Intraductal papillomas are small tumors that grow in the lactiferous ducts, often beneath the areola. These present with serous or bloody discharge and are associated with a slightly increased risk of carcinoma. Phyllodes tumor, which may become malignant, is a large tumor of connective tissue and cysts that presents in postmenopausal women.
Diagnosis and Treatment
Breast cancer can be tested in many ways, including determination of whether the cancer cells are stimulated by the presence of the hormones. This type of exam measures a person’s hormone receptor (HR) status and tests for a positive or negative result which, respectively, corresponds to stimulation or lack of the cancer cell. The test uses the hormones estrogen and progesterone to test a tumor for cancer. If the test is positive for either estrogen or both estrogen and progesterone, then hormone therapy is usually the course of action for the treatment of the cancer in lieu of more intensive treatments. Hormone therapy can also be advantageous because it can help prevent the recurrence of cancer in both the breast and other parts of the body.
Another way of determining whether or not a tumor is malignant is by testing for the amount of protein in the tumor. The human epidermal growth factor receptor 2 (HER-2/neu) test can detect if there is an abnormally high amount of protein in the tumor. During the HER-2 exam, physicians use oncogene measurements to measure how quickly the cells in the tumor are growing. A positive HER-2 result indicates a higher-than-normal growth rate, which is indicative of either abnormally high levels of protein in the cancer cells or overexpression of the HER-2 gene, which causes too much protein to be produced. The treatment of tumors that test positive for the HER-2 exam utilize therapies that specifically target the HER-2 gene to reduce the amount of protein being produced, thus slowing the growth rate of the tumor.
The course of action for a cancer ultimately depends on the progression of the cancer. On a scale of I–IV, cancers in stages I–III are often treatable and the focus turns toward curing the patient of the cancer. In these stages, treatment involves a lumpectomy, the removal of a lump or small part of the breast, or a quadrantectomy, the removal of a quarter part of the breast in addition to other therapies. In the more advanced types of stage IV cancers, however, the focus turns from attempting to cure the cancer to improving the quality of life and increasing their chances of a longer survival. Treatment of stage IV cancer often leads to the patient receiving mastectomy (removal of the whole breast), in combination with chemotherapy, radiation therapy, and/or hormone therapy.
Krishna S. Vyas
University of Kentucky College of Medicine
Arthur Lemons III
Walisha Bland-Lemons
University of Kentucky
See Also: Breast: Cell Types Composing the Tissue; Breast: Development and Regeneration Potential; Breast: Existing or Potential Regenerative Medicine Strategies.
Further Readings
Atkins, Kristen and Christina Kong. Practical Breast Pathology: A Diagnostic Approach. Philadelphia: Elsevier Saunders, 2013.
Breast Cancer Care. “Sclerosing Lesions of the Breast.” Breast Cancer Care: The Breast Cancer Support Charity (February 21, 2013).
“Breast Pathology.” John Hopkins Medicine (n.d.) http://www.hopkinsmedicine.org/avon_foundation_breast_center/treatments_services/breast_cancer_diagnosis/breast_pathology/ (Accessed May 2014).
Chen, Yi-Bin. “Breast Cancer.” Medline Plus: Trusted Health