Table of Contents
Information about causes, risk factors, symptoms, and special types of mammary carcinoma is in the following article: Breast Cancer (Mammary Carcinoma) — Causes, Classification, and Symptoms.
Diagnosis of Breast Cancer (Mammary Carcinoma)
Patient history and clinical examinations in cases of breast cancer
History and physical examination comprise the cornerstone of treating patients with every disease, including breast cancer. Though patients with breast cancer are often asymptomatic, it is important to ask targeted questions regarding any symptoms (changes in the size of the breast, differences between both sides, skin retraction, etc.), and individual risk factors.
The physical examination should be done with the patient’s upper body unclothed and the patient’s arms down, and with the arms raised up. In women, palpation should be done after the end of menstruation. It is important to palpate the supraclavicular and axillary lymph nodes.
Diagnostic tools for mammary carcinoma
Traditionally, women were encouraged to regularly perform breast self-exams and palpation but the current U.S. Preventive Services Task Force (USPSTF) recommends against breast self-examination because it does not reduce breast cancer–related mortality and leads to excessive anxiety.
Therefore, a regular breast exam, self-exam, or an examination by a healthcare practitioner is not recommended. Still, all women should be familiar with the look and feel of their breasts and must consult a healthcare provider if they notice any changes.
Mammography is the gold standard of the instrument-based examination of the breast for the early detection of mammary carcinoma.
The USPSTF recommends biennial (every 2 years) screening mammography for women between the ages of 50–74 years.
In women younger than 50 years of age, the decision to start screening mammography should be individualized depending upon the patient’s risk factors.
Mammography is a specific type of low-dose X-ray imaging in which radiopaque structures such as carcinoma, calcifications, or fibroadenomas create shadows but appear light on the scan, whereas fatty tissue appears dark.
While benign tumors mostly appear homogenous, smoothly outlined, and dense, the following criteria are signs of malignant findings:
- Asymmetric focal findings with delineation that is not sharp
- Non-homogeneous band- and mesh-like shadows
- Star-shaped thickening with spicules
- Polymorphic clustered microcalcifications (indicative of ductal carcinoma in situ (DCIS))
- Surrounding tissue: retraction phenomenon
- Outlined thickening/retraction (skin and mammillary gland)
Note: Polymorphic, clustered microcalcifications are suspicious and are between 80–90% a sign of in situ or early-stage carcinoma, respectively. Mammography has a sensitivity of between 85–90%, depending on the tissue density: The fattier the tissue, the better the sensitivity. The specificity, however, is very limited.
Mammography findings are classified according to the Breast Imaging-Reporting and Data System (BI-RADS), as follows:
|BI-RADS||Diagnosis/findings||Procedure||Risk of carcinoma|
|0||Imaging has not been concluded||Further clarification is necessary||–|
|1||Unremarkable findings||Normal care||0%|
|2||Benign findings||Normal care||0%|
|3||Unclear, probably benign findings||Requiring follow-up (after 6 months)||< 2%|
|4||Suspect findings||Histologic clarification||2–90%|
|5||Suspecting carcinoma||Histologic clarification||> 90%|
|6||Histologically confirmed carcinoma||–||100%|
Other imaging diagnostic tools
In addition to the aforementioned methods, the following tests may be done:
- The most important complementary test in addition to mammography
- Benefit: no radiation exposure, differentiates solid (such as a benign fibroadenoma or cancer) from fluid-filled cystic (such as a benign cyst) lesions
- Disadvantage: highly operator dependent, not suitable for screening
- Imaging of the milk-producing ducts using contrast agent injections, followed by X-rays with mammillary gland secretion
- Pathologic findings: caliber fluctuations in the milk ducts, discontinue contrast agent
3. Magnetic resonance tomography (MRT)
- Conclusive findings are only possible with contrast agents.
- Benefit: high soft-tissue contrast, very high sensitivity
- Disadvantage: low specificity, no detection of microcalcifications
If metastases are suspected, pre-therapeutic staging to include chest X-rays, liver sonography, and skeletal scintigraphy should be pursued.
Biopsy and histology
The histologic examination of the suspected breast cancer is important to confirm the diagnosis of breast cancer, the type of breast cancer, the grade of breast cancer, the presence of certain receptors and genes, and to further plan therapy. For this purpose, breast tissue samples are collected from the suspicious area by way of minimally invasive procedures and subsequently examined microscopically.
Immunohistochemical staining of tumor cells is used in the diagnosis of tumors and may determine therapy. The hormone receptors (estrogen, progesterone, and steroid hormones), and the growth factor receptors (human epidermal growth factor receptor 2 (HER2)/neu), play a role.
If more than 10% of the tumor cells stain positive for estrogen and/or progesterone receptors (ER/PR), the mammary carcinoma is hormone-receptor positive. This means that it is suitable for endocrine therapy and has a better prognosis.
In cases of invasive mammary carcinoma, HER2/neu is over-expressed, which is referred to as HER2 positive. This status of over-expression indicates the direction of therapy: In cases of HER2/neu positive cancer, patients are treated with trastuzumab, a HER2 antibody.
The breast cancer must be differentiated from benign breast lesions, such as the following:
- Cystic changes
Therapy of Breast Cancer
Neoadjuvant therapy is the therapy that is given before surgery in order to shrink large tumors.
Surgery is the main treatment for breast cancer. It includes either radical mastectomy or breast-conserving surgery with the same goal of removing the tumor and affected regional lymph nodes.
Breast-conserving treatment (BCT) followed by radiation therapy is the standard surgical treatment of care. The prerequisite is that the tumor has not yet infiltrated the surrounding tissue and there is a favorable ratio between the size of the tumor and the volume of the breast.
- Lumpectomy: The lump (tumor) is removed along with the removal of 1 cm of healthy tissue on all sides. In some cases, the removal of the nipple may be necessary as well. The removal of the axillary lymph nodes is done with a second incision.
- Quadrantectomy: The quadrant of the breast where the tumor is located is removed and the axillary lymph nodes.
If the tumor is large, multicentric, or if the patient is contraindicated for post-surgery radiation, BCT is not an option. In these situations, a modified radical mastectomy is performed.
During this procedure, the breast, the axillary lymph nodes, and the pectoral fascia are removed, while the pectoral musculature (as opposed to a Halsted radical mastectomy) is preserved. In cases of inflammatory mammary carcinomas, there is an indication for a mastectomy, as well.
Women must be educated on the option of breast reconstruction, which may take place simultaneously or after a latent period of at least 6 months. Suitable materials include heterologous implants or autologous tissue. Autologous tissue allows for the following flap technique reconstructions:
- Thoraco-epigastric flap reconstruction
- Latissimus dorsi flap reconstruction
- (Transverse) rectus abdominis (myocutaneous) flap reconstruction (TRAM)
Note: Both mastectomy and BCT should be regarded as equal with regard to survival rates, whereby the risk for a local recurrence is elevated for patients who have undergone BCT.
In order to determine a patient’s nodal status, it is necessary to perform a lymphadenectomy. When the lymph nodes are removed, there is an increased risk of lymphedema.
If the tumor is < 3 cm in size, the axillary lymph nodes have not been affected and, if there are no contraindications (i.e. a multifocal, multicentric, metastasizing, or inflammatory mammary carcinoma, Paget’s disease), the sentinel lymph node should be removed.
During this procedure, the lymph node that is attacked by the tumor cells first because of the lymph flow (sentinel/guardian lymph node) is marked via injection of peritumoral subdermal dye or radionuclide.
If this lymph node is free of a tumor (sentinel negative), the removal of the axillary lymph node is not necessary, resulting in reduced shoulder–arm morbidity.
If the sentinel lymph node is positive, axillary dissection with removal of a minimum of 10 lymph nodes is indicated.
Adjuvant therapy of mammary carcinoma
Adjuvant therapy takes place after the resection of the tumor, with the goal of reducing the risk of a local recurrence and eliminating potential tumor cells in the body. This can be systemically achieved via local radiation, chemotherapy, or via endocrine or monoclonal antibody therapy, respectively.
Adjuvant postoperative radiation following BCT is an obligatory measure in order to reduce the risk of local recurrence. Following a mastectomy involving large tumors (post-surgical T3 (pT3), primary tumor stage 4 (pT4)), in cases of skin infiltration or extensive lymphangiosis, and if more than three axillary lymph nodes are affected, adjuvant radiation therapy is indicated.
Chemotherapy is indicated if there is an increased risk of recurrence and it should begin 1–2 weeks following surgery. The most frequent medications used are a combination of cytostatic drugs for which regular recommendations are established in the guidelines.
In cases of HER2/neu–positive cancers, it is imperative to administer the monoclonal antibody trastuzumab for 1 year in addition to chemotherapy (see above).
For ER-/PR-positive women (see above), endocrine therapy is indicated. The goal is estrogen deprivation in order to decrease the growth of carcinoma cells. The standard medication currently being used is tamoxifen. Another option for premenopausal patients is the administration of gonadotropin-releasing hormone (GnRH) analogs in order to suppress ovarian function. Aromatase inhibitors are indicated for postmenopausal patients.
Follow-up, Prognosis, and Prevention of Mammary Carcinoma
Follow-up care in mammary carcinoma
After locoregional primary therapy, regular follow-ups are recommended, usually every 3 months during the first 3 years, every 6 months during the fourth and fifth year, and annually after the sixth year. After a mammary carcinoma, the risk of contralateral breast cancer is two to five times higher, which is why there should be an annual instrument-based check-up in that area, as well.
The prognosis of breast cancer depends on multiple factors, including tumor stage, grade, HER2/neu, and hormone receptor status. The earlier it is detected and treated, the better the prognosis. In early breast cancers, the therapy is curative. This underlines the importance of breast cancer screening in women.
Note: The most important prognosis factor with regard to remote metastases is if the axillary lymph nodes are affected.
In cases of remote metastases (in 5% of patients when they are first diagnosed and in 30% of patients during the progression of the disease), therapy will take a palliative course because healing is no longer possible. The median survival time is approximately 2 years and the 5-year survival rate is between 5–10%.
In order to prevent mammary carcinoma (primary prevention), the following options are available:
- In cases of hereditary mammary carcinoma, a bilateral mastectomy with a risk reduction of 90% and/or a bilateral adnexectomy with a risk reduction of 50% should be considered.
- In cases where the patient is at increased risk, drug therapy with tamoxifen, strictly according to the indication, may be an option.
Early detection screenings serve as secondary prevention (see above).