Cancer that starts in the lymph nodes or has spread (metastasized) there from other parts of the body can cause adenopathy.
This article will go over adenopathy in cancer, including why the lymph nodes can swell in cancer and how adenopathy can affect cancer diagnosis and treatment.
What Are Lymph Nodes?
Lymph nodes are small, bean-shaped organs that produce and store blood cells (called lymphocytes) that help fight infection and disease. There are roughly 600 of these nodes throughout the body. Their primary role is to filter waste from the lymphatic fluid. As they do so, the lymphocytes work to neutralize any foreign substance they encounter.
While some lymph nodes are located superficially—in the groin, armpit, and neck, for example—others are situated deeper in the body, such as in the chest or abdomen.
Adenopathy in Cancer
Cancer adenopathy is the term used to describe the swelling of the lymph nodes due to cancer. Cancers that start in the lymph nodes are called lymphoma. Two of the more common types are Hodgkin lymphoma and non-Hodgkin lymphoma. Each behaves and develops differently, but both originate in the lymphocytes themselves. Adenopathy is just one of the features of these diseases.
More commonly, cancer adenopathy will occur when a malignancy in one part of the body (known as the primary tumor) spreads to other parts of the body to create new (secondary) tumors. The lymph nodes are the organs most commonly affected by this.
How Cancer Spreads Through the Lymph Nodes
When a tumor metastasizes, cancer cells break away from the primary tumor and spread to other parts of the body through either the circulatory (blood) system or the lymphatic system.
That said, you cannot diagnose the cause of adenopathy by physical characteristics alone. In some cases, a cancerous node may press on a nearby nerve and cause pain. In others, a benign node may be hard and relatively painless (such as those that can happen with persistent generalized lymphadenopathy seen in HIV).
When the cells are in the blood, they are swept along in the blood flow until they get stuck somewhere, usually a capillary. From this point, the cell can slip through the capillary wall and create a new tumor wherever it landed.
A similar thing happens with the lymphatic system. In this case, cancer cells break off and are carried to the lymph nodes, where they get stuck. While the nodes will respond with an aggressive immune attack, some cancer cells will survive to form a new tumor.
But here is where the difference lies: Unlike the circulatory system, which can carry cancer cells to almost any part of the body, the distribution of cancer through the lymphatic system is more constrained. The nodes nearest the tumor will typically be the first affected. From there, additional cells can break off and move to distant nodes in other parts of the body.
Because of how lymph nodes are affected, healthcare providers will routinely check them to see if cancer has started to spread and, if so, by how much.
Diagnosis
The enlargement of superficial lymph nodes can often be detected through a physical examination. Imaging tests such as computed tomography (CT) scans can also be used, particularly for lymph nodes in the chest or abdomen.
Additionally, the healthcare provider may order a lymph node biopsy. The biopsy involves the removal of lymph node tissue for examination under a microscope. It would be used to see if cancer has spread from a primary tumor or in cases where lymphoma is suspected.
The biopsy can either be performed by surgically removing a node or, less commonly, by removing cells using a less invasive procedure called fine needle aspiration. The biopsy results are important for both the diagnosis and staging of cancer.
How Adenopathy Affects Cancer Treatment
Adenopathy on its own does not alter the course of cancer treatment. However, having cancer cells in your lymph nodes can affect treatment insofar as it will inform the stage of your disease.
One of the most common systems for staging cancer is the TNM system, which is based on the extent of the tumor (T), the extent of spread to the lymph nodes (N), and the presence of metastasis (M). If no cancer is found in the lymph nodes near the tumor, the N will be assigned a value of 0. If nearby or distant nodes show cancer, the N will be assigned a value of either 1, 2, or 3 depending on:
How many nodes are involvedWhere the nodes are locatedHow big the nodes areHow much cancer is in them
The recommended course of treatment will largely be based on the staging. The staging will also provide the diagnosis ICD-10 code, which your health insurer will use to approve treatment.
Summary
Adenopathy, or swollen lymph nodes, can be caused by a variety of things, including cancer. When secondary tumors form or when metastasis occurs, the lymph nodes can be affected, and swell. A lymph node biopsy may be done to see if there is cancer in the lymph nodes. This also impacts the stage of the cancer diagnosed.
A Word From Verywell
If cancer is in the lymph nodes, this is part of the cancer staging process, and treatment will be based on the stage and type of cancer. Treatment can vary depending on the amount of cancer, how large the nodes are, and the extent of lymph node involvement. Talk with your treatment team about your specific diagnosis and how much lymph node involvement exists, and the treatment plans.
With that being said, if your lymph nodes are persistently swollen or become larger, you should contact a healthcare provider.
