Breast lymphoma is a very rare form of non-Hodgkin lymphoma. Usually, the only symptom is an enlarging, painless lump in the breast. Treatment with chemotherapy is usually effective.

Breast lymphoma is a rare type of non-Hodgkin lymphoma (NHL). NHL is a type of cancer that affects immune system cells.

Breast lymphoma occurs almost exclusively in females, and the average age at diagnosis is 60–65 years.

Due to its rarity, experts do not have much data on symptoms, causes, or treatments.

This article discusses what breast lymphoma is, the symptoms associated with it, treatment options, and more.

Sex and gender exist on spectrums. This article will use the terms “male,” “female,” or both to refer to sex assigned at birth. Click here to learn more.

Breast lymphoma develops in the breast. However, it is not a type of breast cancer. Breast lymphoma develops in the lymphocytes (a type of white blood cell), whereas breast cancer develops in the breast tissue.

Breast lymphoma is a rare type of NHL.

Primary breast lymphoma (PBL) accounts for less than 1% of malignant breast tumors and less than 2% of extranodal lymphomas. There are several subtypes of PBL. However, the most common is diffuse large B-cell lymphoma.

Breast lymphoma usually affects one breast. Only 11% of cases occur in both breasts.

Learn more about NHL here.

There are two types of breast lymphoma. They include:

  • Primary breast lymphoma (PBL). This means the lymphoma first appears in the breast tissue with no presence elsewhere.
  • Secondary breast lymphoma (SBL). This occurs when lymphoma starts elsewhere and spreads to the breast. It is the most common metastasis to the breast (accounting for about 17% of all cases).

The cause of PBL is unknown. A 2020 review suggests that it may originate from the mucosa-associated lymphoid tissue, which is lymphatic tissue close to the breast ducts or lobes. It may also develop from intra-mammary lymph nodes.

As PBL occurs almost exclusively in females, some experts have proposed that the hormone estrogen could play a role in its development.

Breast implants and breast lymphoma

Breast implants can trigger a type of non-Hodgkin lymphoma called breast implant-associated anaplastic large-cell lymphoma (BIAALCL). BIAALCL is not the same condition as breast lymphoma.

Symptoms of BIAALCL occur, on average, 8–10 years after implant surgery.

The Food and Drug Administration (FDA) notes that BIAALCL is typically found around the scar tissue near the implants. However, it can appear in other areas.

Like breast lymphoma, BIAALCL is extremely rare, occurring in around 1 in 500,000 people with breast implants.

A person may not have any symptoms of PBL. In 12% of cases, doctors discover it when someone has a mammogram for another reason.

The most common symptom of PBL is a painless, enlarging mass or tumor that a person can feel beneath the skin.

People living with SBL may experience symptoms similar to non-Hodgkin lymphoma due to cancer outside the breast.

Symptoms can include:

  • night sweats
  • fever
  • unexplained weight loss

These symptoms are not common in PBL.

A doctor will not be able to diagnose breast lymphoma from a person’s symptoms. They will need to order tests to examine the tumor.

Diagnostic tests and procedures include:

To diagnose PBL, doctors take a biopsy and send it to a laboratory to check for specific features. With PBL, there is no evidence that the disease has spread to other organs. Typically, a person will have no previous diagnosis of lymphoma.

Due to its rarity, there is no consensus about the best way to treat breast lymphoma, although chemotherapy is the standard treatment.

Surgery does not affect survival risk or chance of recurrence, so doctors usually only use it for diagnostic purposes or in some other instances.

Other treatment options include:

Although chemotherapy may be the most recognized and effective treatment, it can cause unpleasant side effects. They include:

  • hair loss
  • fatigue
  • infections
  • easy bruising or bleeding
  • constipation
  • anemia
  • changes in appetite
  • nausea and vomiting
  • changes in urine
  • diarrhea
  • issues with the mouth, tongue, and throat
  • damage to nerves, such as tingling, pain, and numbness
  • brain fog and focus issues
  • weight changes
  • skin and nail changes
  • issues with fertility
  • changes in mood
  • decreased sexual function and libido

Learn more about the most common side effects of chemotherapy.

The outlook for people with breast lymphoma is relatively good.

According to an article in the Journal of the National Cancer Institute, the 5-year relative survival rate for PBL was 90% for people diagnosed between 2005–2012. This means that people with PBL were 90% as likely to be alive 5 years after diagnosis as people without the condition.

Survival rates were slightly lower for people with breast lymphoma in both breasts.

There are limited statistics for breast lymphoma because it is such a rare disease. A person can talk with a doctor about how their condition will affect them.

If a person notices a lump forming in their breast, they should contact a doctor as soon as possible. A doctor can perform diagnostic tests to determine the cause of the growth.

Breast lymphoma is rare, which means a doctor may not immediately recognize or have much knowledge of the condition.

Breast lymphoma is a rare type of non-Hodgkin lymphoma. It may occur as a primary condition, developing in the breast, or may result from metastasis.

The exact causes are unknown. Often, the only symptom a person has is a growing, painless lump in the breast.

Treatment usually involves chemotherapy. However, it can also involve radiotherapy, immunotherapy, surgery, or a combination of treatments.

Following treatment, people with breast lymphoma have a relatively high chance of survival.