Introduction: Who Should Undergo Diagnostics
If you notice painless swelling in your neck, armpit, or groin, it’s important to see your doctor. These swollen areas might be enlarged lymph nodes, which are small structures throughout your body that help fight infections. While not all swollen lymph nodes mean cancer, persistent swelling should be checked.[1]
You should also seek medical attention if you experience symptoms like heavy sweating at night, high temperatures that come and go without obvious cause, feeling very tired, or losing a lot of weight without trying—especially if you lose more than one-tenth of your body weight. Doctors call fever, night sweats, and significant weight loss “B symptoms,” and they are important to report.[1]
Some people with follicular lymphoma don’t have any symptoms at all. The disease can be discovered during routine check-ups or tests done for other reasons. This is why regular health screenings are valuable—they can catch conditions early, even before you feel unwell.[4]
Follicular lymphoma most commonly affects adults over age 60, though it can occur in younger people too. If you have persistent symptoms or your doctor finds something unusual during an examination, diagnostic tests will be the next step to find out what’s happening inside your body.[1]
Classic Diagnostic Methods
Physical Examination
The diagnostic journey often begins with a physical exam. Your doctor will carefully check for swollen lymph nodes in your neck, underarms, and groin. They will also feel your abdomen to see if your spleen or liver is enlarged. This hands-on examination gives your doctor important clues about where the lymphoma might be located.[6]
Lymph Node Biopsy
A biopsy is the only way to know for sure if you have follicular lymphoma. During this procedure, a doctor removes all or part of a swollen lymph node. The sample is then sent to a laboratory where specialists examine it under a microscope. This is called a lymph node biopsy.[6]
There are different ways to perform a biopsy. Sometimes doctors remove an entire lymph node, which is called an excisional biopsy. Other times, they might take just a small piece using a needle. The type of biopsy depends on where the lymph node is located and how easy it is to reach. The tissue sample will show whether the cells are cancerous and what type of lymphoma is present.[4]
Once follicular lymphoma is confirmed, specialists in the lab will look at how the cancer cells are arranged and count how many large abnormal cells are present. This helps them assign a grade to your lymphoma—grade 1, 2, 3A, or 3B. Grades 1, 2, and 3A are considered slow-growing, while grade 3B grows faster and may need different treatment.[5]
Blood Tests
Blood tests are an important part of diagnosing follicular lymphoma. These tests help rule out infections or other conditions that might cause similar symptoms. They also check your overall health and how well your organs are working.[6]
One specific blood test measures the level of lactate dehydrogenase (LDH), a substance that can be higher if the lymphoma is changing into a more aggressive type. Blood tests can also check your red blood cell count, white blood cell count, and platelet count. Low numbers might mean the lymphoma is affecting your bone marrow, where blood cells are made.[1]
Bone Marrow Biopsy
To find out if cancer cells have spread to your bone marrow, you may need a bone marrow test. Bone marrow is the soft tissue inside your bones where blood cells develop. During this procedure, a doctor uses a needle to collect a small sample of bone marrow, usually from your hip bone.[6]
There are actually two parts to this test: bone marrow aspiration draws out liquid marrow, and bone marrow biopsy removes a small piece of solid tissue. Both samples go to a lab for examination. Finding cancer cells in the bone marrow helps doctors understand the extent of the disease and plan treatment accordingly.[6]
Imaging Tests
Imaging tests create pictures of the inside of your body, showing where lymphoma is located and how far it has spread. These tests are painless and non-invasive, meaning they don’t require surgery or needles entering your body.[6]
CT scans (computed tomography scans) use X-rays taken from different angles to create detailed cross-sectional images of your body. A CT scan can show enlarged lymph nodes in your chest, abdomen, or pelvis that can’t be felt during a physical exam.[1]
PET scans (positron emission tomography scans) use a small amount of radioactive sugar that cancer cells absorb more than normal cells. This makes the cancer light up on the scan, helping doctors see all the places where lymphoma is present. Often, PET and CT scans are done together (called a PET-CT scan) to give the most complete picture.[1]
MRI scans (magnetic resonance imaging) use magnets and radio waves instead of radiation to create detailed images. MRI is especially helpful for looking at the brain, spinal cord, or soft tissues.[6]
Cancer Staging
After all the tests are complete, your doctor will determine the stage of your follicular lymphoma. Staging describes how much of your body is affected by cancer and where it’s located. Follicular lymphoma is staged from I to IV.[1]
In Stage I, cancer is found in only one group of lymph nodes or in one area outside the lymph nodes. Stage II means cancer is in lymph nodes on the same side of your diaphragm—the muscle that separates your chest from your abdomen. Stage II specifically involves two or more groups of lymph nodes or nearby structures, but they’re all either above or below the diaphragm.[1]
Since follicular lymphoma often doesn’t cause symptoms early on, many people are diagnosed at stage III or IV. However, even advanced stages can often be managed successfully with treatment. Your doctor will explain what your stage means for you and discuss the best treatment options.[1]
Diagnostics for Clinical Trial Qualification
If you’re considering joining a clinical trial, additional tests might be needed to see if you qualify. Clinical trials are research studies that test new treatments or new ways of using existing treatments. They follow strict rules about who can participate to ensure the study results are accurate and safe.[13]
To enter a clinical trial for follicular lymphoma stage II, you’ll typically need all the standard diagnostic tests we’ve already discussed: a confirmed biopsy showing follicular lymphoma, imaging tests like PET-CT scans to determine the stage, blood tests to check your overall health, and possibly a bone marrow biopsy.[5]
Researchers running clinical trials need to know exactly what type and stage of lymphoma you have, what grade it is, whether you’ve had previous treatments, and how well your organs are functioning. This information helps them match you with the right study and ensures that the new treatment being tested is appropriate for your situation.[6]
Some trials might require additional specialized tests that aren’t part of routine diagnosis. For example, they might need extra tissue samples to study specific biomarkers—substances in your blood or tissue that give information about your cancer. These biomarkers can help predict how the cancer will behave or how well a treatment might work.[15]
Your medical team will explain what tests are needed for any trial you’re considering. Don’t hesitate to ask questions about why each test is necessary and what the results might mean. Clinical trials can offer access to new treatments that aren’t yet widely available, but it’s important to understand what you’re signing up for.[13]




