Lymphoma
Cancer can develop in any part of the body from tissue and bones all the way to your blood. Lymph nodes, an important part of your immune system, are often part of the discussion with a cancer diagnosis. When lymph nodes become swollen or sensitive, it can mean the body is combating an infection. If the lymph nodes don't return to their normal size after a few weeks, it can be a sign of cancer. Let's look at the difference between cancer that starts in your lymph nodes, called lymphoma, and cancer that spreads to your lymph nodes and how they're different.
Understanding the Lymphatic System and Lymph Nodes
The lymphatic (lymph) system is part of your body's immune system that consists of a network of lymph vessels and lymph nodes. Lymph vessels transport a clear, watery fluid known as lymph, which contains infection-fighting white blood cells.
Lymph nodes are small, bean-shaped glands that act as filters for foreign substances, including cancer cells and infections. They are packed with immune cells that help fight infections by attacking and destroying germs that flow in through the lymph fluid. If you've ever been sick, you may have noticed "swollen glands" in your neck; these are your lymph nodes working hard to protect your immune system from waste products such as bacteria and viruses detected by the lymphatic system.
Lymph nodes are found throughout the body, with clusters of them in areas such as the neck, armpit, chest, abdomen, and groin. However, the lymphatic system also includes the spleen, thymus, tonsils, and bone marrow, where white blood cells originate.
What Is Lymphoma?
Cancer that begins in the lymphatic system or the lymph nodes is known as lymphoma. Lymphoma occurs when healthy cells in the lymphatic system change and grow uncontrollably. Cancer cells turn off your body’s natural ability to identify them as dangerous, so the lymph system doesn’t fight them off as a foreign substance.
Lymphoma is a broad term for a group of blood cancers that develop in lymphatic system cells. The main categories, which develop from different types of lymphocytes (a kind of white blood cell in the immune system), include:
- Hodgkin lymphoma - This type of lymphoma usually starts in B lymphocytes. Nearly all cases have abnormal B lymphocytes called Reed-Sternberg cells. Hodgkin lymphoma is less common but generally more treatable.
- Non-Hodgkin lymphoma - This is the more common type of lymphoma and can originate from multiple types of lymphocytes, including B and T lymphocytes. It includes a range of lymphatic cancers that require different treatment approaches.
Related read: How Are Hodgkin Lymphoma and Non-Hodgkin Lymphoma Different?
Lymphoma can spread rapidly from the lymph nodes to other parts of the body by traveling through the lymphatic system. In the early stages, abnormal lymphocytes grow in the lymph nodes. As the disease progresses, these abnormal cells may begin to grow in other areas of the body. Any cancer that originates in the lymphatic system but spreads to another area within the body is still considered lymphoma, not a new type of cancer.
Common signs and symptoms of lymphoma may include:
- Fever
- Fatigue
- Unintentional weight loss
- Painless swelling of lymph nodes in the belly, neck, armpits, or groin that doesn’t go away
- Frequent infections
- Unusual bleeding or bruising
These symptoms do not necessarily indicate that you have lymphoma. However, it's important to talk to your doctor about any symptoms that last more than a couple of weeks, so they can find the cause and treat it, if necessary.
What Does It Mean When Cancer Spreads to the Lymph Nodes?
Sometimes, cancer cells can break away from a tumor that originates somewhere other than the lymph nodes and migrate to other areas of the body through the bloodstream or the lymphatic system. If cancer cells travel through the lymphatic system, they may end up collecting in lymph nodes. Once the cancer is found in the lymph nodes, it is possible for the cells to move to other areas of the body and form tumors away from the point of origin. This process of cancer spreading to a different part of the body is known as metastasis.
When cancer spreads to lymph nodes, it typically affects those nearest to the original tumor first. These nearby (regional) nodes are primarily responsible for filtering out or killing cancer cells. Still, cancers can also spread to distant lymph nodes located further away from the original tumor site if left untreated.
Regardless of whether the affected lymph nodes are near the original location or elsewhere, it is an indication that the cancer is progressing. Treatment plans are based on whether cancer is present in the lymph nodes and if so, how many.
Breast cancer, lung cancer, melanoma, and gastrointestinal cancers are examples of cancers that commonly spread to lymph nodes.
Key Differences Between Lymphoma and Cancer in the Lymph Nodes
There are some important differences between lymphoma and cancer found in the lymph nodes worth noting.
Primary Cancer vs Cancer Spread
Lymphoma is classified as a primary cancer, meaning it originates in the lymphatic system. In contrast, cancer that appears in the lymph nodes is typically considered a secondary cancer because it has metastasized (spread) from a different primary site.
Diagnosis Differences
The diagnosis and staging processes for these two types of cancer also differ. Diagnosing and staging lymphoma often involves procedures such as bone marrow aspiration and biopsy, complete blood count (CBC) tests, imaging scans, and lymph node biopsies.
While some of the same tests may be used for other types of cancer, in many cases, the lymph nodes are evaluated during surgery to remove the cancer by testing the sentinel lymph node -- the one closest to the tumor to see if it’s been affected. If it has, additional treatments are likely to be sure all cancer cells in the body are destroyed.
Treating Lymphoma vs Cancer that Spreads to Lymph Nodes
Treatment approaches also vary depending on whether the patient has lymphoma or another type of cancer affecting the lymph nodes. Common treatments for lymphoma include systemic treatments, including chemotherapy, targeted therapy, and immunotherapy. Radiation therapy is only used if lymphoma has developed into a tumor. If lymphoma comes back, treatment may involve a bone marrow transplant.
For other types of cancer that spread to the lymph nodes, treatment is determined by the origin of the primary cancer. For example, if breast cancer spreads to the lymph nodes, the treatment plan will need to include systemic treatments such as chemotherapy and/or targeted therapy to kill the cancer cells in all areas of the body. Additionally, the affected lymph nodes will usually be surgically removed to avoid the further spread of cancer cells.
What is the Outlook for Patients Who Have Lymphoma or Cancer in the Lymph Nodes?
A patient's prognosis typically depends on several factors, including the type and stage of lymphoma or primary cancer, their age, overall health, and how well the cancer responds to treatment.
Fortunately, advancements in the treatment of lymphoma and metastatic cancer are allowing for more positive outcomes, enabling individuals to live longer, fuller lives.
Related read: What’s New in Lymphoma Treatments?
Expert Cancer Specialists at WVCI
Understanding the difference between lymphoma and metastatic cancer found in the lymph nodes is important, as this distinction helps oncologists and hematologists determine the most effective treatment and management strategies for the patient.
At Willamette Valley Cancer Institute, our team includes specialists in lymphoma as well as other primary types of cancer who can help you determine the best treatment approach for your particular diagnosis. Whether you were diagnosed with lymphoma or another type of primary cancer, our patient-centered care ensures that we will support you every step of your cancer care journey.
Request a consultation with one of our cancer specialists in Albany, Corvallis, Eugene, Florence, Lincoln City, Newport, or Springfield, Oregon, to learn more about your specific diagnosis and the next steps for treatment.
