Practice Essentials
Breast cancer is the common term for a set of breast tumor subtypes with distinct molecular and cellular origins and clinical behavior. Most of these are epithelial tumors of ductal or lobular origin (see the image below). Worldwide, breast cancer is the most frequently diagnosed life-threatening cancer in women and the leading cause of cancer death among women.
Breast cancer. Intraductal carcinoma, comedo type. Distended duct with intact basement membrane and central tumor necrosis.
See the following:
Cutaneous Clues to Diagnosing Metastatic Cancer, a Critical Images slideshow, to help identify various skin lesions that are cause for concern.
Breast Lumps in Young Women: Diagnostic Approaches slideshow to help manage palpable breast lumps in young women.
Oncology Decision Point for expert commentary on breast cancer treatment decisions and related guidelines.
Signs and symptoms
Early breast cancers may be asymptomatic, and pain and discomfort are typically not present. If a lump is discovered, the following may indicate the possible presence of breast cancer:
Change in breast size or shape
Skin dimpling or skin changes
Recent nipple inversion or skin change, or nipple abnormalities
Single-duct discharge, particularly if blood-stained
Axillary lump
SeePresentation for more detail.
Diagnosis of breast cancer
Breast cancer is often first detected as an abnormality on a mammogram before it is felt by the patient or health care provider.
Evaluation of breast cancer includes the following:
Clinical examination
Imaging
Needle biopsy
Physical examination
The following physical findings should raise concern:
Lump or contour change
Skin tethering
Nipple inversion
Dilated veins
Ulceration
Paget disease
Edema or peau d’orange
If a palpable lump is found and possesses any of the following features, breast cancer may be present:
Hardness
Irregularity
Focal nodularity
Fixation to skin or muscle
Screening
Early detection remains the primary defense in preventing breast cancer. Screening modalities include the following:
Breast self-examination
Clinical breast examination
Mammography
Ultrasonography
Magnetic resonance imaging
Ultrasonography and MRI are more sensitive than mammography for invasive cancer in nonfatty breasts. Combined mammography, clinical examination, and MRI are more sensitive than any other individual test or combination of tests.
Biopsy
Core biopsy with image guidance is the recommended diagnostic approach for newly diagnosed breast cancers. This is a method for obtaining breast tissue without surgery and can eliminate the need for additional surgeries. Open excisional biopsy is the surgical removal of the entire lump.
See Workup for more detail.
Management of breast cancer
Surgery and radiation therapy, along with adjuvant hormone or chemotherapy when indicated, are considered primary treatment. Surgical therapy may consist of lumpectomy or total mastectomy. Radiation therapy may follow surgery in an effort to eradicate residual disease while reducing recurrence rates. There are 2 general approaches for delivering radiation therapy:
External-beam radiotherapy (EBRT)
Partial-breast irradiation (PBI)
Surgical resection with or without radiation is the standard treatment for ductal carcinoma in situ.
Pharmacologic agents
Hormone therapy and chemotherapy are the 2 main interventions for treating metastatic breast cancer. Common chemotherapeutic regimens include the following:
Docetaxel
Cyclophosphamide
Doxorubicin
Carboplatin
Methotrexate
Trastuzumab
HER2-targeted therapies have been investigated in combination with angiogenesis inhibitors, with promising results. HER2 overexpression is associated with an increase in VEGF levels in primary breast cancers. Dual blockade by antiangiogenic/HER2 agents (eg, neratinib) targeting HER2, and EGFR pathways produces greater inhibition of human breast cancer cell lines.
In patients receiving adjuvant aromatase inhibitor therapy for breast cancer who are at high risk for fracture, the monoclonal antibody denosumab or either of the bisphosphonates zoledronic acid and pamidronate may be added to the treatment regimen to increase bone mass. These agents are given along with calcium and vitamin D supplementation.
See Treatment and Medication for more detail.
Prevention
Two selective estrogen receptor modulators (SERMs), tamoxifen and raloxifene, are approved for reduction of breast cancer risk in high-risk women. Prophylactic mastectomy is an option for women found to be at extremely elevated risk.