Cancer can spread to the lymph nodes via a person’s lymphatic system. From here, it can travel through the lymphatic system to other parts of the body.
The spread of cancer to a new part of the body is called metastasis. Cancer cells can travel to other areas of a person’s body through their lymphatic system.
Read on to learn more about what it means when cancer spreads to the lymph nodes and the treatment available.
A person’s lymphatic system is part of their immune system. The lymphatic system is a series of connected nodes and vessels.
Lymph vessels transport a substance called lymph fluid around a person’s body. Lymph fluid contains white blood cells, which help fight infections.
Lymph nodes are small structures that filter foreign substances, such as bacteria and cancer cells, from the lymph fluid. Lymph nodes also contain white blood cells that attack invading organisms in the lymph fluid.
Cancer cells that appear in a person’s lymph nodes have broken away from the original tumor and traveled via the lymph vessels to a lymph node.
The presence of cancer cells inside a lymph node indicates that cancer is spreading. Cancer cells that survive inside the lymph node may then travel to other parts of the body.
The rate that cancer spreads to a person’s lymph nodes may depend on the type of cancer. Some spread quickly to the lymph nodes, while others develop and spread more slowly.
The stages of cancer indicate how far cancer has traveled from its original location.
There are different ways of staging cancer,
- Stage 0, or carcinoma in situ (CIS), is when abnormal cells are present but have not spread.
- Stage 1, 2, and 3 indicate that cancer is present. The higher the stage, the larger and more extensive the cancer is.
- Stave 4 is when cancer has spread to areas that are distant from the original tumor.
Healthcare professionals also break stages into further subcategories, using a, b, and c.
The staging will depend on the type of cancer. For some cancers, lymph node involvement occurs at stage 2, but in others it can mean cancer has reached stage 3.
Another way of staging cancer is the TNM staging system. In the TNM system, each letter refers to a different feature of the cancer:
- T refers to the size of the original tumor
- N refers to the number of nearby lymph nodes that have cancer cells
- M refers to whether cancer has metastasized (spread)
When a doctor uses the TNM system, they will place a number after each letter. This number provides additional information:
|Number beside the N||Meaning|
|X||Cancer in the nearby lymph nodes is not measurable.|
|0||No cancer is present in the nearby lymph nodes.|
|1, 2, or 3||These N numbers refer to the location and amount of lymph nodes that contain cancer. As the number after the N increases, so does the number of lymph nodes affected.|
Cancer cells in the lymph nodes usually indicate that cancer is spreading.
The outlook for cancer that has spread to lymph nodes will depend on the type of cancer.
For example, the American Cancer Society (ACS) defines the 5-year relative survival rate as follows for cancer that has regionally advanced, including spread to the nearby lymph nodes:
86%for breast cancer 37%for non-small cell lung cancer 18%for small cell lung cancer 68%for melanoma
A relative survival rate helps people understand what chance a person has of living of a certain number of years after receiving a diagnosis compared with those without the condition.
What does the survival rate mean?
If the 5-year relative survival rate for breast cancer with lymph node involvement is 86%, it means a person with that diagnosis is 86% as likely to live for 5 years as someone without it.
The survival rate often falls once cancer reaches the lymph nodes. According to the
These figures are estimates based on the results of previous studies and treatment options. A doctor can explain how cancer is likely to affect an individual.
An early diagnosis and treatment can
Various treatments can address cancer that has spread to lymph nodes. The options will depend on the type of cancer and other factors.
Treatments for cancer that has spread to lymph nodes include:
- surgery to remove the person’s primary cancer and any affected lymph nodes
- chemotherapy, which uses drugs to kill cancer cells
- immunotherapy, which boosts a person’s immune system to fight cancer cells
- targeted therapy, which uses drugs to identify and attack specific cancer cells
- radiation therapy, which uses high-energy particles or waves to destroy cancer cells
A surgeon may remove the lymph nodes if they contain cancer cells. This can help stop the spread of cancer but may have another adverse effect.
Once a surgeon removes any lymph nodes, the lymph fluid in that area
This can sometimes lead to a buildup of lymph fluid in the lymph vessels, called lymphedema.
It can cause swelling and pain in the affected area, and it may be a long-term problem.
They are usually too small to notice. But, if cancer is present, they can become large and swollen.
Lymph nodes that contain small number of cancer cells may not appear swollen. It can also be hard to notice swollen lymph nodes that are deep inside the body.
If a doctor suspects a person has cancer, they may perform a biopsy on lymph nodes near the primary location. This will show if cancer has reached the lymph nodes.
If cancer cells are present, a doctor may use the following categories to describe them:
- Isolated cells: There are fewer than 200 cancer cells in the lymph node, or there is a tumor of no more than 0.2 millimeters (mm) in size.
- Micrometastasis: At least 200 cancer cells are present in the lymph node, or the tumor is 0.2–2 mm in size.
- Macrometastasis: There is a tumor in the lymph node that measures over 2 mm.
- Extracapsular extension: Cancer has spread beyond the wall of the lymph node.
If a person with a cancer diagnosis notices swelling in the lymph nodes or any other new symptoms, they should speak with a doctor.
The sooner a person receives treatment for cancer that has spread, the better the outcome will be.
Here are some questions people often ask about cancer spreading to the lymph nodes.
How serious is it if cancer spreads to the lymph nodes?
Cancer in the lymph nodes is usually a sign that cancer is starting to spread, but it is often treatable. How serious it is will depend on many factors, such as the type of cancer, the rate at which it is growing, the person’s overall health, and the treatment options available.
What is the survival rate when cancer spreads to the lymph nodes?
This will depend on the type of cancer, the treatment available, and other factors. For people with breast cancer, the 5-year survival rate when cancer is only in the breast is
Is cancer treatable when it spreads to the lymph nodes?
Cancer that has spread to the lymph nodes is treatable through surgery, chemotherapy, radiotherapy, and other approaches. However, treatment can never guarantee that cancer will disappear completely or never come back.
Cancer can spread to other parts of a person’s body via the lymphatic system. A lymph node biopsy can help a doctor determine if cancer is spreading or not.
The chances of cancer spreading to the lymph nodes may depend on the type of cancer.
If a person with a cancer diagnosis notices new swelling in the lymph nodes or other new or unusual symptoms, they should speak with a doctor. Prompt treatment can reduce the chances of cancer spreading further.