Breast cystic hyperplasia, also referred to as mammary dysplasia, lobular hyperplasia, breast structural dysplasia, or fibrocystic disease, is commonly observed in middle-aged women. The pathological morphology of this condition varies widely. Hyperplasia may occur around the ducts, accompanied by the formation of cysts of varying sizes, which often contain clear yellow or brownish fluid. It may also manifest as varying degrees of papillary hyperplasia within the ducts, along with ductal cystic dilation. In some cases, the condition involves the lobular parenchyma, primarily characterized by epithelial hyperplasia of the ducts and acini.
Etiology
The condition is caused by an imbalance in female hormones, particularly between estrogen and progesterone, leading to excessive proliferation and incomplete regression of breast parenchymal tissue. Abnormalities in the quality and quantity of estrogen receptors in certain areas of the breast may also result in uneven degrees of hyperplasia across different parts of the breast.
Clinical Manifestations
The primary clinical manifestations are breast tenderness or pain and the presence of lumps, which may occur in one or both breasts. Some patients experience symptoms that are cyclic in nature. Breast tenderness tends to worsen before menstruation and subside afterward, although in severe cases, the pain may persist throughout the entire menstrual cycle. Physical examination may reveal diffuse or localized thickening within one or both breasts, as well as palpable lumps that are often firm and indistinctly demarcated from surrounding normal breast tissue, without adhesion to the overlying skin. A small number of patients may also experience nipple discharge, often presenting as clear or pale yellow serous fluid. This condition may be influenced by the patient’s emotional state, and the disease progression is typically slow, with a prolonged course.
Diagnosis
The diagnosis is primarily based on clinical manifestations, with attention given to ruling out the possibility of coexisting breast cancer. Patients are recommended to undergo re-evaluation every 3–6 months. When localized breast hyperplastic lumps are prominent, differentiation from breast cancer is necessary. Breast cancer tends to present with more defined masses that are firmer in texture, sometimes accompanied by enlarged axillary lymph nodes. Imaging studies can aid in the differentiation between the two conditions.
Treatment
The treatment primarily focuses on symptomatic relief. Emotional regulation may be provided to patients. If the lump does not show significant regression after medical therapy or if there is concern for potential malignancy during clinical observation, a biopsy may be indicated. Patients with moderate to severe atypical hyperplasia who also have high-risk factors, such as contralateral breast cancer or a family history of breast cancer, may be considered for simple mastectomy.