Breast Cancer Screening and Diagnosis
Breast cancer is the second most commonly diagnosed cancer among women, after skin cancer. The incidence of breast cancer increases with age.
Risk Factors for Breast Cancer
• Age greater than 50 years
• Prior history of breast cancer
• Family history
• Early menarche, before age 12
• Late menopause, after age 50
• Age greater than 30 at first birth
• High socioeconomic status
• Atypical hyperplasia on biopsy
• Ionizing radiation exposure
Family history is highly significant in a first-degree relative (ie, mother, sister, daughter), especially if the cancer has been diagnosed premenopausally.
Women who have premenopausal first-degree relatives with breast cancer have a three- to fourfold increased risk of breast cancer. Having several second-degree relatives with breast cancer may further increase the risk of breast cancer. Most women with breast cancer have no identifiable risk factors.
Approximately 8 percent of all cases of breast cancer are hereditary. About one-half of these cases are attributed to mutations in the BRCA1 and BRCA2 genes. Hereditary breast cancer commonly occurs in premenopausal women. Screening tests are available that detect BRCA mutations.
Diagnosis and evaluation
Clinical evaluation of a breast mass
should assess duration of the lesion, associated pain, relationship to the menstrual cycle or exogenous hormone use, and change in size since discovery. The presence of nipple discharge and its character (bloody or tea-colored, unilateral or bilateral, spontaneous or expressed) should be assessed.
The date of last menstrual period, age of menarche, age of menopause or surgical removal of the ovaries, previous pregnancies should be determined.
History of previous breast biopsies
, cyst aspiration, dates and results of previous mammograms should be determined.
should document breast cancer in relatives and the age at which family members were diagnosed.
The breasts should be inspected for asymmetry, deformity, skin retraction, erythema, peau d'orange (breast edema), and nipple retraction, discoloration, or inversion.
The breasts should be palpated while the patient is sitting and then supine with the ipsilateral arm extended. The entire breast should be palpated systematically. The mass should be evaluated for size, shape, texture, tenderness, fixation to skin or chest wall.
A mass that is suspicious for breast cancer is usually solitary, discrete and hard. In some
instances, it is fixed to the skin or the muscle. A suspicious mass is usually unilateral and
nontender. Sometimes, an area of thickening may represent cancer. Breast cancer is rarely bilateral. The nipples should be expressed for discharge.
The axillae should be palpated for adenopathy, with an assessment of size of the lymph nodes, number, and fixation.
Screening mammograms are recommended every year for asymptomatic women 40 years and older. Unfortunately, only 60 percent of cancers are diagnosed at a local stage.
Methods of breast biopsy
Palpable masses. Fine-needle aspiration biopsy (FNAB)
has a sensitivity ranging from 90-98%. Nondiagnostic aspirates require surgical biopsy.
The skin is prepped with alcohol and the lesion is immobilized with the nonoperating hand. A 10 mL syringe, with a 14 gauge needle, is introduced in to the central portion of the mass at a 90° angle. When the needle enters the mass, suction is applied by retracting the plunger, and the needle is advanced. The needle is directed into different areas of the mass while maintaining suction on the syringe.
Suction is slowly released before the needle is withdrawn from the mass. The contents of the needle are placed onto glass slides for pathologic examination.
Excisional biopsy is done when needle biopsies are negative but the mass is clinically suspected of malignancy.
Stereotactic core needle biopsy.
Using a computer-driven stereotactic unit, the lesion is
localized in three dimensions, and an automated biopsy needle obtains samples. The sensitivity and specificity of this technique are 95-100% and 94- 98%, respectively.
Needle localized biopsy
a. Under mammographic guidance, a needle and hookwire are placed into the breast
parenchyma adjacent to the lesion. The patient is taken to the operating room along
with mammograms for an excisional breast biopsy.
b. The skin and underlying tissues are infiltrated with 1% lidocaine with epinephrine.
For lesions located within 5 cm of the nipple, a periareolar incision may be used or use a
curved incision located over the mass and parallel to the areola. Incise the skin and
subcutaneous fat, then palpate the lesion and excise the mass.
c. After removal of the specimen, a specimen x-ray is performed to confirm that the lesion has been removed. The specimen can then be sent fresh for pathologic analysis.
d. Close the subcutaneous tissues with a 4-0 chromic catgut suture, and close the skin
with 4-0 subcuticular suture.
Screening is useful to differentiate between solid and cystic breast masses when a palpable mass is not well seen on a mammogram. Ultrasonography is especially helpful in young women with dense breast tissue when a palpable mass is not visualized on a mammogram. Ultrasonography is not used for routine screening
because microcalcifications are not visualized and the yield of carcinomas is negligible.