Nipple Discharge: Symptoms, Causes and Treatment

Nipple discharge is a common breast-related complaint, often causing significant concern for those who experience it. While most cases are benign and self-limited, some types of nipple discharge can signal underlying conditions that require closer evaluation or intervention. Understanding the symptoms, possible causes, and treatment strategies is crucial for both patients and healthcare professionals. This comprehensive guide synthesizes the latest research to offer an evidence-based overview of nipple discharge.

Symptoms of Nipple Discharge

Nipple discharge can present in a variety of ways, from subtle and intermittent to conspicuous and persistent. Recognizing the key symptoms and their characteristics is the first step in understanding when nipple discharge may be a normal occurrence and when it warrants further investigation.

Symptom	Description	Significance	Source(s)
Color	Milky, multicolored, sticky, purulent, clear, yellow, pink, bloody	Certain colors more indicative of pathology	2, 5, 7
Unilateral/Bilateral	Discharge from one or both nipples	Unilateral is higher risk	2, 7
Spontaneous/Provoked	Occurs without or with manipulation	Spontaneous is more concerning	4, 6
Associated Lump	Presence of a breast mass	Strong predictor of malignancy	3, 4, 6
Persistent	Duration over time, whether intermittent or constant	Persistence increases risk	2, 6

Table 1: Key Symptoms

Common Presentations

Nipple discharge can be classified by its appearance and the circumstances under which it occurs. Some presentations are more likely to be benign, while others may suggest a need for further assessment.

• Milky Discharge: Usually associated with hormonal causes or lactation. It is generally benign unless accompanied by other symptoms such as a mass or occurs in someone not pregnant or breastfeeding 2, 5.
• Multicolored/Sticky: Often benign, sometimes due to duct ectasia or benign papillomas 2, 5.
• Purulent (Pus-like): Suggests infection or abscess; may be accompanied by redness or tenderness 2, 5.
• Clear, Yellow, Pink, or Bloody: These are considered surgically significant and may indicate a higher risk of underlying pathology, including cancer 2, 7.

Risk Factors in Symptomatology

Certain features increase the likelihood that the discharge is due to a significant underlying cause:

• Unilateral Discharge: More likely to be pathologic, especially if from a single duct 2, 7.
• Spontaneous Discharge: Occurring without squeezing or manipulation is more concerning than discharge provoked by pressure 4, 6.
• Associated Mass: The presence of a lump along with discharge greatly increases the risk of malignancy 3, 4, 6.
• Persistent or Recurring: Discharge that does not resolve or keeps returning should be evaluated further 2, 6.

Age and Symptom Significance

• Older age, particularly women over 50, is associated with a higher risk of the discharge being related to cancer, especially when combined with other suspicious features 2, 7.
• Younger women, particularly those under 35, are more likely to have benign causes 2.

Causes of Nipple Discharge

Understanding the wide range of potential causes is essential for appropriate diagnosis and management. While most cases are benign, some are linked to precancerous or cancerous conditions, making a thorough evaluation critical.

Cause	Prevalence in ND Cases	Typical Features	Source(s)
Intraductal Papilloma	30–49%	Often bloody or serous discharge	2, 3, 4, 6
Fibrocystic Changes	12–42%	May present with lump, pain	2, 3, 6
Duct Ectasia	10–35%	Multicolored, sticky discharge	3, 5, 6
Carcinoma	4–28% (higher in SND)	Persistent, unilateral, bloody	2, 3, 4, 6, 7
Infections/Abscess	Variable	Purulent, painful	2, 5
Nipple Adenoma	Rare	Serous or bloody discharge, erosion	1
Endocrine Disorders	Uncommon	Milky discharge, galactorrhea	2, 5

Table 2: Common Causes

Benign Causes

• Intraductal Papilloma: The most frequent benign cause, responsible for up to half of surgical cases. Typically presents with spontaneous, often bloody or serous discharge 2, 3, 4, 6.
• Fibrocystic Changes: These changes in breast tissue can cause lumps, pain, and discharge, often in women of reproductive age 2, 3, 6.
• Duct Ectasia: Involves dilation and inflammation of milk ducts, leading to sticky, multicolored discharge. More common as women approach menopause 3, 5, 6.
• Nipple Adenoma: A rare, benign tumor of the nipple itself, presenting with serous or bloody discharge and sometimes with nipple erosion 1.

Malignant Causes

• Carcinoma: Although less common than benign causes, breast cancer is a critical consideration. It accounts for around 4–28% of cases requiring surgery, with higher rates in women with spontaneous, persistent, unilateral, and bloody discharge, especially if over age 50 or a mass is present 2, 3, 4, 6, 7.
  • Ductal carcinoma in situ (DCIS) is a common type found in these cases 8.
• Precancerous Mastopathy: Represents a smaller fraction but is still clinically significant 2.

Infections and Endocrine Causes

• Mastitis and Abscess: Infections can produce purulent discharge, often with redness, swelling, and pain. Abscesses may require drainage 2, 5.
• Endocrine Disorders: Conditions like pituitary adenomas can cause milky discharge (galactorrhea) unrelated to pregnancy or breastfeeding 2, 5.

Other Factors

• Provoked vs. Spontaneous Discharge: Spontaneous discharge is more likely to have a significant underlying cause, particularly cancer, compared to discharge only elicited by manipulation 4, 6.
• Age and Hormonal Status: Older women and those with a history of multiple pregnancies or extended lactation are at higher risk of malignant causes in cases of spontaneous discharge 6.

Treatment of Nipple Discharge

Management strategies for nipple discharge depend on the underlying cause, the risk of malignancy, and how bothersome the symptom is for the patient. The goal is to identify cases requiring intervention while avoiding unnecessary procedures in benign conditions.

Treatment	Indication	Approach/Outcome	Source(s)
Observation/Follow-up	Low-risk features, negative imaging	Most resolve without surgery	7, 8, 9
Medical Therapy	Milky, multicolored, infectious causes	Nipple hygiene, antibiotics, hormonal meds	2, 5
Duct Excision	Persistent, bothersome, high-risk cases	Resolves discharge, removes lesion	2, 4, 7, 9
Surgery for Malignancy	Cancer detected or suspected	Tumor excision, oncologic care	2, 3, 4, 8
Imaging & Biopsy	Suspicious findings on exam or imaging	Guides further management	7, 8, 9

Table 3: Treatment Approaches

Clinical Assessment and Initial Management

• Detailed History and Physical Exam: Includes assessment of discharge features (color, laterality, spontaneity), presence of a mass, and patient risk factors 5.
• Imaging: Mammography and ultrasound are recommended for most women with pathologic discharge, especially if over 40 or with suspicious features 7, 8, 9.
  • If imaging is normal and the discharge is low-risk (not bloody, bilateral, provoked), many can be safely observed 7, 8.
• Laboratory Tests: Serum prolactin and thyroid-stimulating hormone may be checked in cases of milky discharge not explained by pregnancy or lactation 9.

Observation and Non-Surgical Management

• Close Clinical Follow-up: For low-risk cases (e.g., negative imaging, non-bloody discharge), observation is recommended. Most patients will see resolution without intervention 7, 8.
• Medical Therapy:
  • Milky Discharge: Rule out pituitary adenoma; bromocriptine may be used for persistent, unexplained cases 2.
  • Infectious Causes: Treated with antibiotics. Abscesses may need drainage and biopsy 2, 5.
  • Nipple Hygiene: For multicolored, sticky, or mild discharges 2.

Surgical Management

• Duct Excision (Microdochectomy or Central Duct Excision): Indicated for:
  • Persistent, bothersome discharge resistant to conservative measures.
  • Discharges with high-risk features (spontaneous, unilateral, bloody, or associated with a mass) even if imaging is negative 2, 4, 7, 9.
  • Offers good cosmetic outcomes and eliminates recurrent discharge risk 2.
• Surgery for Malignancy:
  • If cancer is diagnosed or highly suspected, standard breast cancer treatment protocols are followed, which may include lumpectomy, mastectomy, and oncologic therapies as appropriate 2, 3, 4, 8.

Modern Algorithms and Patient Selection

• Risk Stratification: Age over 50, abnormal imaging, and high-risk discharge features guide the need for surgical intervention 7, 8.
• Minimizing Unnecessary Surgery: Most patients with low-risk features and negative imaging can be managed without surgery, reducing morbidity and cost 7, 8, 9.

Special Populations

• Women Under 35 or Desiring Fertility: Surgery is often avoided unless absolutely necessary, due to potential impact on breastfeeding and breast tissue 2.
• Patients with No Clinical or Imaging Findings: Regular follow-up is key, with instructions to report any changes 4.

Conclusion

Nipple discharge is a frequent concern and can be a source of anxiety. While it is most often benign, certain features may indicate a more serious underlying condition and require prompt evaluation.

Main Points:

• Nipple discharge is common and most often benign, but can sometimes indicate cancer or other significant pathology 2, 3, 4, 5, 7.
• Symptoms such as unilateral, spontaneous, persistent, or bloody discharge, especially in older women or with a mass, are high risk and require further assessment 2, 3, 4, 6, 7.
• The most common causes are intraductal papilloma, fibrocystic changes, and duct ectasia, with carcinoma less frequently but importantly implicated 2, 3, 4, 6.
• Modern evaluation emphasizes careful history, physical exam, and imaging, with observation for low-risk cases and surgery reserved for persistent or high-risk discharges 7, 8, 9.
• Timely recognition and appropriate treatment can ensure both reassurance and safety for patients experiencing nipple discharge.

If you or someone you know experiences nipple discharge, especially with concerning features, prompt medical evaluation is recommended for peace of mind and optimal outcomes.