OVERVIEW

What is mammary gland hyperplasia?

Mammary gland hyperplasia is a benign breast disease caused by endocrine hormone disorders, leading to abnormal development and degeneration of the mammary glands^[1].

It mainly manifests as breast nodules or lumps, breast tingling, and may be accompanied by nipple discharge. It is common in women aged 30 to 50.

Mammary gland hyperplasia is a benign condition and does not significantly harm health. If obvious discomfort occurs, symptoms can be improved through medication, lifestyle adjustments, or psychological counseling.

However, if malignancy is suspected or the hyperplasia is severe, surgical treatment may be required.

What are the types of mammary gland hyperplasia?

According to the "Expert Consensus on the Diagnosis of Mammary Gland Hyperplasia" proposed by the Breast Health and Disease Prevention Group of the Women's Health Branch of the Chinese Preventive Medicine Association, mammary gland hyperplasia can be classified into:

• Lobular hyperplasia type
• Fibroadenosis type
• Ductal hyperplasia type
• Sclerosing adenosis type
• Cyst type
• Fibrotic nodule type
• Cystic hyperplasia type^[1]

The aforementioned types of mammary gland hyperplasia may coexist in the same patient or occur independently.

Can men develop mammary gland hyperplasia?

Yes. Male mammary gland hyperplasia is a common type of male breast disease^[2].

SYMPTOMS

What are the clinical manifestations of mammary gland hyperplasia?

• Breast pain: Manifested as distending pain, stabbing pain, or tenderness upon touch, with varying degrees of severity. Mild pain may go unnoticed, while severe pain may affect daily life. The pain of adenosis is mostly cyclical, worsening before or during menstruation and significantly alleviating after menstruation. Cystic hyperplasia often presents as localized, non-cyclical pain. Some pain may also be related to fatigue or emotional stress.
• Breast lumps: The lumps are not adherent to surrounding tissues, feel resilient rather than hard, and may appear as single, multiple, or even diffuse masses. They are movable and may shrink or soften after menstruation, with unclear boundaries from the surrounding breast tissue.
• Nipple discharge: 3.6%–20% of patients may experience nipple discharge, which is typically clear, colorless, or pale yellow/milky white. Yellow or bloody discharge does not occur.

Can mammary gland hyperplasia develop into breast cancer?

Simple mammary gland hyperplasia is not associated with breast cancer.

However, some atypical hyperplasias, such as cystic hyperplasia and intraductal papilloma (intraductal papillomatosis), are considered precancerous lesions and may progress to breast cancer.

CAUSES

What are the common causes of mammary hyperplasia?

The exact cause of mammary hyperplasia is not yet clear, but it may be related to endocrine disorders and excessive estrogen secretion leading to a relative decrease in progesterone.

Before each menstrual period, most people with mammary hyperplasia experience breast swelling and pain due to elevated estrogen levels in the body. Additionally, factors such as mental state, marriage and childbirth, breastfeeding, diet, environment, genetics, and lifestyle habits may also play a role.

Which women are more prone to mammary hyperplasia?

• Women with more than one induced abortion, older age at first childbirth (the risk of mammary hyperplasia is about twice as high in those over 30 compared to those under 25), or short cumulative breastfeeding duration (less than 3 months)^[3,4];
• Long-term high-fat diet and alcohol consumption;
• Experiencing intense emotional stress or long-term emotional suppression^[3];
• Breast augmentation procedures or frequent use of breast-enhancing products;
• Ill-fitting bras;
• Early menarche (before age 12) or late menopause (age 50 or older)^[3,5];
• Long-term smokers.

Is mammary hyperplasia related to sexual activity?

Yes. The breasts are not only organs for lactation but also sexual organs. During sexual activity, the breasts become engorged, the areola reddens, the nipples erect, and the breast veins fill with blood. After orgasm, these changes gradually subside.

Long-term lack of sexual activity may increase the risk of mammary hyperplasia and breast cancer^[6].

Is mammary hyperplasia hereditary?

There is currently no evidence to suggest that this condition is hereditary.

DIAGNOSIS

What examinations will doctors perform for patients with mammary hyperplasia?

• Physical examination: The doctor will palpate the patient's breasts to check for tenderness, lumps, nipple discharge, and swelling of axillary lymph nodes.
• Imaging tests: The doctor may recommend mammography and/or breast ultrasound to observe any breast lumps and preliminarily assess whether they are benign or malignant.
• Patients with nipple discharge may undergo ductoscopy or ductography combined with cytological examination to rule out other conditions. Breast MRI and CT scans are less commonly used but may serve as auxiliary diagnostic tools.
• Pathological examination: If mammary hyperplasia is suspected to be another condition, the doctor may arrange for a breast lump biopsy (needle or surgical excision) to rule out breast cancer, fibroadenoma, or other diseases.

When is the best time for patients with mammary hyperplasia to undergo examinations?

It is generally recommended to schedule examinations 3–5 days after menstruation ends. Symptoms such as breast pain and lumps are more pronounced before and during menstruation but often subside afterward, allowing for a more objective evaluation. Male patients experiencing breast discomfort should seek medical attention promptly.

Which examination method is more suitable for patients with mammary hyperplasia?

• For women under 35 with dense breast tissue, breast ultrasound is the preferred method, as it outperforms mammography.
• For older women with less glandular tissue, mammography is the first choice, as it can detect early-stage or micro-cancers and excels in identifying microcalcifications compared to ultrasound.
• Male patients may undergo high-frequency ultrasound combined with color Doppler to visualize the breast's structure, morphology, and surrounding relationships.
• Doctors will recommend the most appropriate examination based on the patient's specific condition.

What are the manifestations of mammary hyperplasia in breast ultrasound?

Possible findings include:
Enhanced and thickened echoes.

If solid lesions are present, hypoechoic nodules may be observed, typically with irregular borders and unclear margins. Posterior echo may show no attenuation or mild enhancement, with only minimal punctate or short linear blood flow signals within the nodule.

Cysts usually appear as anechoic fluid-filled areas with smooth, sharp boundaries and significant posterior echo enhancement.

What findings of mammary hyperplasia can be seen on mammography?

If a palpable breast lump is present:

• Over half of patients may show patchy or nodular density shadows without clear boundaries, possibly accompanied by coarse, sand-like, rod-shaped, or small arc-shaped calcifications distributed locally or diffusely (with fewer than 10 calcifications per square centimeter).
• Some patients exhibit glandular-density lumps that are relatively uniform but irregular in shape, with blurred or partially clear edges.
• Cystic lesions may appear as uniformly dense, well-defined nodular shadows.

When should patients with mammary hyperplasia undergo needle biopsy or surgical excision of breast nodules?

Pathological examination is the gold standard for diagnosing benign or malignant breast diseases.

However, as it is invasive (involving needle biopsy or surgical excision), it may cause discomfort and financial burden, so it is not recommended for all patients.

For those with clinical and imaging findings suggestive of benign lesions, regular follow-up may suffice without immediate pathological examination.

However, suspicious malignant lumps, localized glandular thickening, or microcalcifications detected on mammography warrant pathological evaluation to exclude malignancy and avoid delayed treatment.

What are the differences between mammary hyperplasia and fibroadenoma?

These are distinct conditions, though both may present with single or multiple firm breast lumps, making differentiation by palpation or imaging alone challenging.

In mammary hyperplasia, lumps vary in size, are often bilateral and multiple, and may be nodular, patchy, or granular. They are usually soft but can be firm, sometimes accompanied by premenstrual pain and cyclical changes in size/texture. It predominantly affects young to middle-aged women.

Fibroadenomas are typically unilateral, solitary (though sometimes multiple), round or oval, well-defined, mobile, and firm. They rarely cause significant pain or cyclical changes and are most common in women under 30, especially ages 20–25. Mammography is key for differentiation.

How do mammary hyperplasia and breast cancer differ?

Both may present with breast lumps, but one is benign while the other is malignant.

In mammary hyperplasia, lumps are usually soft or moderately firm, often bilateral and multiple, varying in size and shape (nodular, patchy, or granular). They are non-adherent, change with menstrual cycles/emotions, grow slowly, and primarily affect younger women. However, some cystic hyperplasias may carry a risk of malignancy.

Breast cancer lumps are typically hard, unilateral, and solitary, with irregular, round, or oval shapes. They may grow rapidly, adhere to surrounding tissues, lack mobility, and show no relation to menstrual cycles. They are more common in older women.

TREATMENT

Which department should I visit for breast hyperplasia?

Thyroid and Breast Surgery Department, General Surgery Department.

How is breast hyperplasia treated?

If there are no symptoms such as pain, treatment may not be necessary. Maintain a regular lifestyle, relax, and reduce high-fat food intake.

If pain affects daily life and work, lifestyle adjustments and psychological counseling can be considered. If necessary, estrogen blockers may be used to relieve pain.

If ultrasound reveals thin-walled cysts, fine-needle aspiration should be performed. For complex cysts, malignancy should be suspected, and cytological examination of bloody aspirate or pathological examination of the lesion is required.

If pathological examination indicates breast hyperplasia with atypical hyperplasia, malignant transformation should be monitored. Large cysts, severe symptoms, or ultrasound findings such as rich blood supply, localized thickening of the cyst wall, or intracystic tumors may require surgical intervention. Surgical options include minimally invasive and open surgery. If financially feasible, minimally invasive surgery can prevent cyst recurrence and minimize scarring.

Can needle aspiration be used to treat breast hyperplasia?

No.

The cyst wall has secretory function, so aspiration alone often leads to rapid recurrence, cyst septation, and infection. Needle aspiration is primarily a diagnostic procedure.

DIET & LIFESTYLE

Can women with mammary gland hyperplasia get pregnant?

Yes, mammary gland hyperplasia does not affect the fetus.

However, it may worsen the condition due to elevated estrogen levels during pregnancy. Patients should remain vigilant and seek medical attention promptly if abnormalities occur.

Can mammary gland hyperplasia be treated with massage?

No. Patients should undergo examination and diagnosis at a正规 hospital, especially those with larger cysts, to avoid rupture from excessive force.

Will mammary gland hyperplasia improve after marriage and childbirth?

Regular sexual activity after marriage can regulate乳腺功能 and benefit mammary gland hyperplasia.

Those with a family history of tumors or excessive anxiety about cancer should consider treatment before pregnancy, as elevated estrogen levels during pregnancy may aggravate the condition.

During lactation, estrogen is suppressed while prolactin secretion increases, which benefits the condition. Breastfeeding is encouraged.

What dietary precautions should women with mammary gland hyperplasia take?

Reduce intake of high-fat foods, limit alcohol consumption, and quit smoking.

What should women with mammary gland hyperplasia consider when choosing underwear?

Opt for slightly looser, well-made, and shape-retaining underwear. Cotton fabric is preferred for its breathability and skin-friendly properties.

PREVENTION

How to Prevent Mammary Gland Hyperplasia?

Following these measures can help prevent the occurrence of mammary gland hyperplasia:

• Women aged 30–50 should undergo a breast examination at a reputable local hospital every six months to a year. If any discomfort is noticed, seek medical attention promptly.
• Maintain emotional stability, optimism, and a balanced lifestyle with proper work-rest routines.
• Those with irregular menstruation should seek timely treatment.
• Breastfeeding after childbirth benefits both the child and the mother.
• Use medications under a doctor’s guidance, avoid estrogen-containing beauty products, and prevent induced abortions. Maintain a healthy diet, limit alcohol, and reduce intake of carbonated drinks, tea, coffee, fried foods, and sweets like fried chicken, chocolate, cake, and ice cream.