Experiencing nipple discharge even though you are not breastfeeding? Depending on the colour, consistency, and occurrence, nipple discharge can be normal. Hormonal imbalances through stress, medication, or conditions such as galactorrhoea are common causes for nipple discharge. However, it can also be a warning sign of issues such as infection and even breast cancer.
But how do we differentiate between normal and abnormal nipple discharge? If you are concerned about what your nipple discharge could mean, read on to understand what nipple discharge is, the causes, and the likelihood that it is related to breast cancer.
Understanding Nipple Discharge
Nipple discharge is the release of fluid through the milk ducts from the nipples. Each breast contains 10-15 milk ducts, and discharge can come from one or more of these ducts.
It is normal to have nipple discharge in the last few weeks of pregnancy and during breastfeeding. Physical stimulation such as squeezing the breast or sexual arousal can also stimulate discharge. Fluid from these causes is usually yellow or milky and is released from both breasts.
Nipple discharge can be concerning when it is bloody or brown or is released persistently and spontaneously i.e. without physical stimulation. This can be accompanied by other signs such as breast pain, dimpled skin, swelling, redness, and nipple inversion.
Common Causes of Nipple Discharge
Nipple discharge is common during hormonal changes from pregnancy and breastfeeding. The fluid released is likely colostrum, a yellowy substance that serves as the first meal for the baby until the breast milk is produced. This is caused by increased prolactin, a hormone that releases milk from the milk ducts. Medications like birth control pills and antidepressants can also increase prolactin levels.
Discharge is normal even if you are not pregnant or breastfeeding. Stimulation of the nipples through massage, breast pumps, or sexual arousal activates the nerves in the nipple and areolas. Consequently, the nerves will signal the brain to release hormones like prolactin and oxytocin to increase milk production and milk duct contraction respectively.
Do note that discharge for men is abnormal regardless of its colour or consistency. Spontaneous and unilateral nipple discharge for women may indicate issues that require a medical examination. Common issues related to nipple discharge include:
- Galactorrhea: Milky nipple discharge unrelated to breastfeeding. While it can be a natural effect of menopause or excessive stimulation, it could also indicate issues unrelated to the breasts including an underactive thyroid or tumour in the pituitary gland, which is responsible for releasing prolactin for milk production.
- Duct ectasia: Dilated milk ducts with thickened duct walls. Consequently, the milk ducts become blocked, leading to a buildup of thick, sticky fluid which can irritate the duct inner linings. This can cause inflammation, breaking down the surrounding tissues which causes the release of white, green, or even bloody discharge.
- Nipple eczema: Irritation of the skin around the nipple. Persistent scratching can break the skin around the nipple, creating open sores vulnerable to bacterial infection, leading to pus discharge. Alternatively, damaged skin can exude fluid that mixes with skin oils and other damaged cells, releasing bloody fluids.
- Mastitis: Inflammation of breast tissues, usually caused by bacterial infection. This can occur when there are open sores in the nipples from breastfeeding. Another reason is milk stasis, whereby milk is not removed from the breast due to infrequent breastfeeding, poor latch, or blocked ducts. The buildup of milk can cause inflammation of the milk ducts, releasing pus that appears yellow, greenish, or even bloody.
- Fibrocystic breast: Presence of fluid-filled cysts in the breast tissues. The breast will feel lumpy and sometimes painful. However, it is usually harmless (hormonal changes during menopause or menstrual cycles) and will resolve on its own.
- Intraductal papillomas: Benign (non-cancerous) tumours inside the milk ducts. This can damage the duct lining, leading to bleeding and the release of cellular debris or dead tissues through the nipple. Fluid is often spontaneously released from a single duct in one breast. If the tumour turns cancerous, it may affect multiple ducts.
Is Nipple Discharge a Warning Sign of Breast Cancer?
Nipple discharge alone is not a strong indication of breast cancer. A study by the Royal College of Surgeons in England found that nipple discharge was observed in only 3% of breast cancer patients. In these cases, discharge is usually spontaneous, unilateral, and bloody or clear discharge. Nonetheless, it is not a sign to be overlooked. Another study acknowledged that nipple discharge, though rare, can be an early sign of breast cancer, especially when accompanied by other symptoms including breast pain, lump, nipple inversion, and skin changes including redness and dimpling.
Certain types of breast cancer are more commonly associated with nipple discharge:
- Ductal carcinoma in situ (DCIS): Cancer cells localised in the inner lining of the milk ducts. It has a good prognosis, with most cases treated with medication like tamoxifen or lumpectomy.
- Invasive ductal carcinoma: Cancer originated in the milk ducts has spread to surrounding breast tissues. Its key features include swelling, lump in the breast, nipple inversion, and abnormal nipple discharge e.g. blood.
- Paget’s disease of the breast: This is a rare condition characterised by the ulceration and lesion of the skin around the nipple and areola. Patients typically experience a burning pain or itch around the nipples. There may also be flaking and crusting of the skin surrounding the nipples.
Risk Factors and Symptoms to Watch For
While anyone can have breast cancer, certain risk factors should be noted:
- Over 40 years old
- Family history of breast cancer
- Genetic mutations e.g. BRCA1 and BRCA2
- Poor lifestyle habits e.g. excessive alcohol consumption, lack of exercise
- Obesity
- Taking hormonal medication or antidepressants that may upset hormonal balance
Diagnostic Procedures
With the advancements in technology, diagnosis has become faster and more accurate. Patients with nipple discharge undergo a triple assessment: physical examination, imaging studies, and cytology. The physician will typically ask for your medical history and symptoms, followed by a physical breast examination. You may be required to place your hands above the head to allow the physician to assess the size, symmetry, shape, texture, and colour of the breast and nipples. Any lumps or changes in the skin such as redness and dimpling will be noted.
To better understand the causes of your nipple discharge, various imaging tests can be performed. This includes mammograms, ultrasounds, and/or magnetic resonance imaging (MRI). This checks for any anomaly in the breast tissues and milk ducts that are invisible to the naked eye such as blockage in the milk ducts, inflammation, and lumps.
Ductography is another imaging procedure to examine the milk ducts. This involves the injection of a dye into the ducts for better visualisation of the ductal system using X-ray. Any blockages indicating ductal ectasia, papillomas, tumour growth and other conditions can be observed. If one is identified, a biopsy may be performed to extract a small breast tissue sample for laboratory examination.
Nipple discharge cytology extracts a sample of the nipple discharge by gently pressing the nipple. In some cases, a small suction device may be used. The discharge is sent for microscopic analysis to look for signs of infection or cancerous cells.
Treatment Options
For hormone-related discharge like breastfeeding and pregnancy, no intervention is required as the discharge may resolve on its own. Hormonal imbalances due to medication may require a discussion with your doctor to switch the dose regime or the type of medication. Hormonal therapy may be recommended for conditions like galactorrhea to restore a healthy level of prolactin.
If you have a bacterial infection, antibiotics will be prescribed. Painkillers such as ibuprofen may be provided to mitigate any breast pain from the condition. Surgery may be required if you have duct ectasia or papillomas to remove any blockages in the milk ducts.
If you have breast cancer, various treatment options are available. The most conservative approach is taken to preserve healthy tissues. Treatment includes:
- Chemotherapy: Involves a combination of drugs to shrink the tumour before lumpectomy, or to kill any remaining cancer cells after surgical removal of the tumour.
- Hormone therapy: For hormone receptor-positive breast cancer, medication to block the estrogen receptors can prevent estrogen from attaching to the cancer cells.
- Radiation therapy: Involves high-energy X-rays to kill the cancer cells.
- Targeted therapy: This is a new area of research to target the cancer cells specifically, reducing side effects on healthy tissues. One example is to target HER2 receptors, which are specifically found in breast cancer cells.
- Lumpectomy: Removal of the tumour
- Mastectomy: Removal of the breast. This is typically the last resort.
When to See a Doctor
Breast cancer is one of the most prevalent cancers among women worldwide. In Singapore, breast cancer is the most commonly diagnosed female cancer among women, with 1 in 13 women diagnosed with breast cancer in their lifetime. However, due to its asymptomatic nature in its early stages, most do not know they have breast cancer until it has progressed to more severe stages.
Hence, it is important to go for regular breast screening to identify any signs of breast cancer invisible to the naked eye. For women aged 40 and above, it is recommended to schedule a mammogram once every year. One should also perform a breast self-examination regularly to check for changes in the breasts.
Nipple discharge can be normal – do not panic and jump to conclusions. However, if you notice any nipple discharge, breast pain, breast lumps or other skin changes, consult a professional immediately. Early detection saves lives by increasing the chance of successful treatment and recovery.
Safeguard Your Health Today
Nipple discharge is not always a cause for panic – it could be due to hormonal imbalances from pregnancy, breastfeeding, medication, or stress. These causes do not require intervention and should resolve on their own.
It becomes a problem if the discharge is bloody and occurs unilaterally, spontaneously, and persistently. If you have other signs like breast pain, nipple inversion or dimpling around the nipples, get it checked as soon as possible. There could be a myriad of reasons, from infection to benign tumours. Breast cancer can be a cause for nipple discharge, though further examination is required to confirm the diagnosis.
At the Centre for Screening and Surgery, we can perform breast screenings to detect both benign breast lumps and breast cancers. We also specialise in minimally invasive procedures for cancer treatment. If you are looking for a breast screening or treatment options, call us to book an appointment today!