Fibrocystic breast or fibrocystic breast diseaseis a condition of breast tissue affecting an estimated 30-60% of women and at least 50% of women of childbearing age. It is characterized by noncancerous breast lumps in the breast which can sometimes cause discomfort, often periodically related to hormonal influences from the menstrual cycle.

Symptoms

The changes in fibrocystic breast disease are characterised by the appearance of fibrous tissue and a lumpy, cobblestone texture in the breasts. These lumps are smooth with defined edges, and are usually free-moving in regard to adjacent structures. The bumps can sometimes be obscured by irregularities in the breast that are associated with the condition. The lumps are most often found in the upper, outer sections of the breast (nearest to the armpit). Women with fibrocystic changes may experience a persistent or intermittent breast aching or breast tenderness related to periodic swelling. Breasts and nipples may be tender or itchy.

Symptoms follow a periodic trend tied closely to the menstrual cycle. Symptoms tend to peak immediately before each period and decrease afterwards. At peak, breasts may feel full and swollen. No complications related to breastfeeding have been found.
Causes

The causes of the condition are not fully understood, though it is known that they are tied to hormone levels, as the condition usually subsides after menopause and is also related to the menstrual cycle.

Fibrocystic breast changes is a cumulative process, caused partly by the normal hormonal variation during a woman's monthly cycle. The most important of these hormones are estrogen, progesterone and prolactin.

These hormones directly affect the breast tissues by causing cells to grow and multiply.Many other hormones such as TSH, insulin, growth hormone and growth factors such as TGF-beta exert direct and indirect effects amplifying or regulating cell growth. Years of such fluctuations eventually produce small cysts and/or areas of dense or fibrotic tissue. Multiple small cysts and an increasing level of breast pain commonly develop when a woman hits her 30s. Larger cysts usually do not occur until after the age of 35.Over time, presumably driven by aberrant growth signals, such lesions may accumulate epigenetic, genetic and karyotypic changes such as modified expression of hormone receptors and loss of heterozygosity.

Several variants of fibrocystic breast changes may be distinguished and these may have different causes and genetic predispostions. Adenosis involves abnormal count and density of lobular units, while other lesions appear to stem mainly from ductal epithelial origins.

Diagnosis

Diagnosis is mostly done based on symptoms after exclusion of breast cancer. Nipple fluid aspiration can be used to classify cyst type (and to some extent improve breast cancer risk prediction) but it is rarely used in practice. Biopsy or fine needle aspiration are rarely warranted.

Tests
- Mammography is usually the first imaging test to be ordered when unusual breast changes have been detected during a physical examination.

- Ultrasounds and MRIs are commonly performed in conjunction with mammographies as they produce clear images of the breast and clearly distinguish between fluid-filled breast cysts and solid masses.

- The breast biopsy is usually the test used to confirm the suspected diagnosing.

Treatment

Most women with fibrocystic changes and no symptoms do not need treatment, but closer follow-up may be advised.

There is no widely accepted treatment or prevention strategy for fibrocystic condition. When treatment of symptoms is necessary it follows the same strategies as treatment for cyclical breast pain.

Usually treated by Progesterone ointments and supplements.
Prognosis

There are usually no adverse side effects to this condition. In almost all cases it subsides after menopause. A possible complication arises through the fact that cancerous tumors may be more difficult to detect in women with fibrocystic changes.

Breast cancer risk

Breast cancer risk is elevated for small fraction of lesions. Nonproliferative lesions have no increased risk, proliferative lesions approximately 2-fold risk. Atypical lobular hyperplasia is associated with the greatest risk, approximately 5-fold and especially high relative risk of developing premenopausal breast cancer. Atypical ductal hyperplasia is associated with 2.4-fold risk.