Mesothelioma & Lymph Nodes: What You Need to Know
October 2, 2017
Most mesothelioma cancer patients and their families know lymph nodes are important, but they don’t necessarily know why.
There are many long, intimidating medical terms you might never hear until you or a loved one receives a rare diagnosis such as pleural mesothelioma.
However, even short words from a doctor can be confusing for cancer patients and their families. After all, just what is a lymph node, and how does the lymphatic system work?
It’s often difficult to find a simple explanation of what your lymphatic system does and why doctors are so concerned about cancer cells getting into it.
But once you understand the basics, you’ll have one less unfamiliar medical term to wonder about.
- Lymph is a fluid that carries waste products from your veins and tissues.
- Lymph nodes filter that fluid to stop infections from spreading.
- If cancer cells spread through the lymphatic system, it may rule out tumor-removing surgery as a treatment option.
Killing Germs Before They Enter Bloodstream
Lymph removes contaminants, such as viruses and bacteria, from your tissues and blood. Lymph vessels flow through a series of filters called lymph nodes, where lymphocytes, which are a type of white blood cell, kill dangerous microorganisms.
Your lymphatic system plays a vital role in your body’s overall immune system because it keeps infections from spreading.
After lymph is filtered through the 500–700 nodes in the human body, it drains back into the bloodstream near the heart, becoming normal blood again.
Unlike the circulatory system which relies on the heart to pump blood throughout the body, the lymphatic system doesn’t have its own pump. Instead, each node acts as a one-way valve, and the lymph is squeezed upward through the lymph vessels when you move your muscles.
If you don’t move, your lymph doesn’t either. That’s why it is important to stay physically active.
When your lymphatic system is dealing with an infection in a particular area, your lymph nodes swell in or near that area.
Certain lymph nodes are so close to your skin you can feel them with your fingers or see them with the naked eye when they are swollen. This is what doctors are checking for when they feel around your ears and neck to see if you are getting sick.
Cancer Cells in Lymph Nodes Signal Late-Stage Cancer
Sometimes cancer cells break from the main part of a tumor and drift away, potentially to grow into a new tumor elsewhere in the body. Doctors call this process metastasis.
The lymphatic system can catch stray cancer cells and trap them in lymph nodes, but there is always a danger that once cancer cells start getting into the lymphatic system, they will overwhelm each lymph node in their way, one by one, until they finally enter the bloodstream.
The most common staging system for pleural mesothelioma is the TNM system, in which cancer first forms at stage 1 and becomes most serious at stage 4. In this system, the N stands for “node” because any cancer spread into lymph nodes automatically signifies late-stage cancer — even if the main tumor mass is still small.
When cancer cells spread into nearby lymph nodes, it usually signals stage 3 cancer. By the time cancerous cells reach distant lymph nodes, a stage 4 cancer diagnosis is most likely.
PET Scans Can Reveal Cancer in Lymph Nodes
Doctors can look for cancerous spread into lymph nodes by using a positron emission tomography (PET) scan. When you get a PET scan, doctors first inject you with a mildly radioactive type of sugar, which is absorbed by cancer cells faster than other cells. The PET scan picks up the radiation from the sugar, revealing where the cancer cells are in the body.
Determining the correct cancer stage is an important part of an accurate mesothelioma diagnosis because the stage guides doctors in developing a treatment plan.
- In general, early-stage cancer is considered resectable, which means a surgeon may be able to remove the tumor through surgery if the patient is in otherwise good health.
- Late-stage cancer is usually considered unresectable, which means the medical team must rely on nonsurgical cancer therapies such as chemotherapy or immunotherapy.
Only an experienced mesothelioma specialist can ensure an accurate diagnosis and the best possible treatment plan. But becoming a well-informed patient guarantees you’ll be prepared to ask questions about your diagnosis, especially when it comes to your lymphatic system and its role in your cancer.