Breast Cancer: Benign Breast Disease

The breast is composed of glandular tissue called lobules. Each of these lobules is drained by 15-20 lactiferous ducts in each breast. The blood supply of the breast is provided by lateral perforating branches of the internal thoracic artery, also known as the internal mammary artery. In 75% of patients, the lateral blood supply of the breast is based on perforating medial branches of the lateral thoracic artery. Medial breast lymph drainage is to the parasternal lymph nodes. Lateral breast lymph drainage is by the axillary nodes. Multiple breasts can develop in both males and females, following a predetermined milk line. Multiple breasts are termed polymastia. If only an extra nipple or areola is present, this is termed polythelia. The unilateral absence of a breast is referred to as Poland’s syndrome. Poland’s syndrome can also be associated with the absence of the pectoralis muscle.

Benign Breast Disease
The initial patient presentation is generally with a complaint of breast pain (mastalgia) or breast lump.

Mastalgia
Rarely does breast pain represent cancer; however a thorough breast exam and evaluation should be performed. Breast pain is characterized as cyclical or noncyclical with treatment as determined by the type of pain present. Cyclic pain is probably hormonal in nature, since it can be associated with elevated prolactin levels and relieved with menopause. Noncyclic mastalgia affects older women and the origin of the pain should be discriminated as chest wall or breast pain.

Management
Treatment can often be with a support bra worn at night. If conservative treatment fails, medicine would be instituted. Medication must be continued for at least two months before being considered a treatment failure. The drug with the least side effects and an average success rate at decreasing pain is gamolenic acid or evening primrose oil. Other medications with efficacy include danazole, a synthetic testosterone (inhibits the gonadotropin surge and enzymes of steroid synthesis) and bromocriptine (a dopamine antagonist).

Breast Lump
Identification of a breast lump is the most common reason patients seek medical attention. Breast lumps in women less than 40 are often benign but should be assessed in a methodical fashion.

Diagnosis
Often now referred to as the triple test, physical exam, mammogram and biopsy are the initial diagnostic methods. Sometimes ultrasound can be used to evaluate a questionable mass. MRI and PET scans are being considered as tools; however, now they are cost prohibitive and have questionable sensitivity and specificity. If the mass is still questionable, then core needle or excisional biopsy can be preformed.

Fibroadenoma
Masses in women less than 40 are most often a fibroadenoma, which develops from abnormal lobule development. Fibroadenomas are composed of stromal and epithelial elements. On a physical exam, these are discrete masses that are freely movable and soft.

Diagnosis
On an ultrasound, they are solid masses that have well circumscribed margins with a heterogeneous echo pattern. On a mammogram, a mass with circumscribed borders is seen. Four types of fibroadenomas exist:
1. Common
2. Giant
3. Juvenile
4. Phyllodes tumor

Giant fibroadenomas are ones that measure greater than 5 cm. Juvenile fibroadenomas are also large and occur in adolescent girls. Phyllodes tumors are seen in premenopausal women. Treatment of phyllodes tumors are with excision; however, they tend to recur. Fibroadenoma will increase in size in 10% of cases while 33% will regress.

Fibroadenomas are a long term risk factor for cancer only if proliferative disease is present or the fibroadenoma is complex. A complex fibroadenoma is one that contains cysts, sclerosing adenosis, epithelial calcifications, or apocrine changes.
A biopsy should be done if:
1. increases in size on ultrasound
2. ≥ 3 cm or greater in size
3. atypia on x-ray or previous biopsy

Fibrocystic Disease
Fibrocystic disease is more common in women around age 40. This disease was first described in 1829 by Astley Cooper, of Cooper’s ligament fame. These cysts form secondary to involution of the breast lobules.

Diagnosis
One to three per cent of cysts have been associated with breast cancer displayed by internal shadows as seen on ultrasound. Abnormal borders are sometimes seen on mammogram. These abnormal cysts should be aspirated and, if bloody, sent for cytology. Cysts should be excised for the following reasons:
1. aspirate is bloody
2. residual mass exists after aspiration
3. persistent refilling after aspiration
Cysts that carry an increased risk of cancer are ones that are palpable or ones that develop in women at a young age.4 Cysts that have atypical hyperplasia also have an increased risk of cancer.

Other Benign Masses
There are other less common benign masses in women. These include lipomas, found in women of all ages. They are soft, fleshy and mobile and are usually diagnosed by excision. Fat necrosis is another benign mass, resulting from trauma. Fat undergoes involution to become a hard palpable mass. Because this mass is hard, distinguishing it from a malignant tumor is difficult. Diagnosis is often made by excision. Lymph nodes in the breast are sometimes palpable, but a mammogram can usually determine this to be a benign lesion.

Breast Abscess
Breast infection sometimes is present as a palpable indurated mass. These are seen in nonlactating and lactating women but are far more common in the latter. Early treatment with antibiotics can prevent abscess formation. Treatment of breast abscess involves drainage of the collection. This can be done with incision and drainage or repeated aspiration and antibiotics, usually nafcillin or amoxicillin, to cover S. aureus. More extensive and loculated collections may be aspirated with ultrasound guidance.

If an underlying lesion is present after treatment, then biopsy must be performed to rule out carcinoma. If the lesion is solid at the first aspiration, biopsy must be performed to rule out inflammatory carcinoma. Treatment of a lactating abscess also includes the continued drainage of milk of the affected segment. Antibiotics that cannot be used in breast feeding mothers include floxins, which causes abnormal cartilage formation; sulfas, an increase in free bilirubin by displacing it from albumin and resulting in secondary kernicterus; or tetracyclines creating abnormal teeth development. Nonlactating abscesses can occur periareolar or peripherally.

Periareolar abscess occur more often in young women that smoke. This, pathologically, is seen as inflammation around nondilated subareolar ducts and can progress to a mammary duct fistula creating a communication between the skin and a subareolar duct. This fistula is usually seen after incision and drainage of an abscess. Treatment is by excision of the fistula and duct and administrating antibiotics. Peripheral nonlactating abscesses are associated with immune compromise. They are seen in diabetics or women with chronic steroid use. Incision and drainage is only done if the overlying skin is compromised.

Nipple Discharge
Another benign complaint is nipple discharge. If the discharge is bilateral, a non-breast source is often the cause. This may indicate an increased prolactin level. This suggests a pituitary tumor or a medication side effect (e.g., an anti-psychotic drug [dopamine blocker] can also stimulate this). Nipple discharge is only worrisome if it is bloody or spontaneously drains from one duct. This can be a sign of an intraductal papilloma or an invasive cancer. The most common cause of bloody nipple discharge is a benign intraductal papilloma. Investigation usually requires a ductogram to isolate the involved duct that, then, undergoes excision.