Lymphoma is a type of cancer that begins in the lymphatic system, a network of organs, tissues, and vessels that produce, store, and carry white blood cells. These white blood cells are responsible for fighting infection and disease.

Lymphomas occur due to changes to the DNA of white blood cells called lymphocytes. Many health experts categorize lymphoma into two major types: non-Hodgkin lymphoma and Hodgkin lymphoma. However, other specialists suggest there are three types, which include small lymphocytic lymphoma (SLL). However, some doctors consider SLL to be a subtype of non-Hodgkin lymphoma.

This article describes what the lymphatic system is and how cancers can develop in this part of the body. It also outlines the types of lymphoma, including associated symptoms, treatments, and outlook.

Image of axillary lymph nodesShare on Pinterest
Smith Collection/Gado/Getty Images

The lymphatic system plays an instrumental role in the body’s ability to fight infections and other diseases. It comprises organs and tissues that produce, carry, and store white blood cells. These include the following:

Many types of white blood cells help the body fight infections and diseases, including:

  • granulocytes, such as neutrophils, eosinophils, and basophils
  • lymphocytes, such as B cells and T cells
  • monocytes

Doctors do not fully understand the causes of lymphoma. However, they know that lymphomas usually develop due to changes within the DNA of B-cell lymphocytes or T-cell lymphocytes.

DNA changes within a lymphocyte can prevent the cell from responding to signals that would ordinarily control its growth. The atypical cells replicate faster or live longer than normal cells, causing them to accumulate in the lymphatic system. These cells that characterize cancer can travel to all parts of the body, both within and outside the lymphatic system.

In most cases, doctors do not know what causes these DNA changes. Some occur as a result of random chance, while some evidence suggests there are links to:

  • age
  • ethnicity
  • sex
  • infections
  • family history
  • radiation and chemical exposure

Lymphoma is the most common type of blood cancer. Some experts suggest there are three main categories of lymphoma:

Non-Hodgkin lymphoma

Non-Hodgkin lymphoma (NHL) is an umbrella term that encompasses more than 60 subtypes of lymphoma. Evidence suggests NHL becomes more common as people get older.

Doctors typically find NHL in the lymph nodes. The various types of NHL may differ in terms of their:

  • appearance under a microscope
  • molecular features
  • growth patterns
  • treatment response
  • effects on the body

Non-Hodgkin lymphomas can affect B cells, T cells, or natural killer cells. B-cell lymphomas are the most common, accounting for 85% of all NHLs.

Medical professionals further categorize NHLs according to whether the cancer is fast-growing, or aggressive, or slow-growing, or indolent.

Symptoms

Some common symptoms of NHL include:

Many conditions with no relation to lymphoma can also cause the above symptoms. However, a person should seek medical advice if symptoms persist for longer than 2 weeks or begin to affect their daily life.

Treatment

The treatment for NHL depends on whether the cancer is fast-growing or slow-growing.

  • Fast-growing NHL: The treatment for fast-growing NHL is chemotherapy with a combination of drugs. These techniques are typically intensive but effective. If large masses are present, a doctor may recommend radiation therapy alongside chemotherapy.
  • Slow-growing NHL: The treatment for slow-growing NHL varies. In some cases, doctors may recommend careful monitoring for any signs of progression. In other instances, they may recommend treatment. The type of treatment is highly individualized and depends on the following factors:
    • the person’s age and overall health
    • the stage of the disease
    • overall outlook

Hodgkin lymphoma

In Hodgkin lymphoma, large, abnormal Reed-Sternberg cells are present in biopsy samples.

This type of lymphoma is most common in young adults between the ages of 15 and 35 and adults over the age of 50 years.

Symptoms

Common symptoms of Hodgkin lymphoma are very similar to NHL and may include:

  • lymph node swelling
  • night sweats
  • fever
  • lack of energy
  • unexplained weight loss

Treatment

Treatment options for Hodgkin lymphoma commonly consist of chemotherapy, radiation therapy, and stem cell transplantation. A doctor will select an appropriate treatment approach according to the following factors:

  • disease subtype
  • disease stage
  • the person’s age and overall health

However, research and clinical trials are ongoing to develop novel agents that may affect treatment.

SLL

SLL resembles chronic lymphocytic leukemia (CLL). However, one difference is that SLL occurs primarily in the lymph nodes, while CLL involves cancerous cells primarily in the bone marrow and bloodstream.

Symptoms

Most people with SLL do not have any apparent symptoms. Instead, doctors typically detect the disease during routine blood tests.

If symptoms of SLL are present, they may include:

Treatment

SLL treatments depend on the severity of a person’s symptoms and the rate of cancer growth.

In cases where symptoms are minimal or nonexistent, doctors may opt for a waiting and monitoring approach.

If symptoms are present or the disease progresses, treatment typically comprises a combination of chemotherapy drugs. The choice of whether to proceed with treatment or a particular treatment strategy depends on several factors, including:

  • the disease stage
  • symptom severity
  • the person’s age and overall health
  • the potential benefits versus side effects of treatment

The outlook for lymphoma depends largely on its subtype.

  • Non-Hodgkin lymphoma: Some types of NHL are curable, while others are not. In noncurable cases, a person may receive treatment or therapies to help manage the condition and optimize their quality of life.
  • Hodgkin lymphoma: More than 80% of people with an HL diagnosis become cured of the disease. Recurrences of this cancer type also tend to be curable.
  • Small lymphocytic lymphoma: The 5-year survival rate for SLL is around 87%. This means that around 87% of people will be live for 5 years following their initial diagnosis and treatment.

The lymphatic system plays an essential role in the body’s immunity. It produces, carries, and stores white blood cells, which fight infections and diseases.

Lymphomas are cancers that develop in white blood cells called lymphocytes. They usually develop in either B-cell lymphocytes or T-cell lymphocytes.

There are three broad categories of lymphomas: non-Hodgkin lymphoma, Hodgkin lymphoma, and small lymphocytic lymphoma. Treatment varies widely across all these types, from monitoring and waiting to intensive chemotherapy with multiple agents.

The outlook for lymphoma depends largely on the subtype. In most cases, the outlook for people with this condition is generally good. This is particularly true of Hodgkin lymphoma, where the vast majority of individuals become cured.