Diagnosis of Follicular Lymphoma

Diagnosing Follicular Lymphoma

What is Follicular Lymphoma?

Follicular Lymphoma is an incurable blood cancer that affects the lymph glands (also called nodes). It is a type of non-Hodgkin lymphoma and is referred to as indolent since it is slow-developing.

The lymphatic system is an integral part of the immune system. The lymph system consists of lymph nodes, spleen and lymphocytes, which are a special type of white blood cells that circulate throughout the blood and lymphatic system. The lymphatic system plays a vital role in helping the body to fight off infections. They do this by trapping and eliminating viruses, bacteria and other harmful substances so they do not infect other parts of your body. Lymphocytes can be classified as B, T or NK cell types based on different functions and markers. B lymphocytes, or B cells, are made by the bone marrow and their main function is to differentiate into plasma cells that make antibodies (immunoglobulins)
specifically to seek out and fight infection.

Lymphoma develops when your body makes abnormal lymphocytes that don’t work properly. The most common lymphomas, including Follicular Lymphoma, come from B cells, so are call B cell lymphoma. These cells multiply, accumulating in the lymph glands, also called lymph nodes, resulting in painless swelling, in one but usually more of the lymph glands. Lymph glands can be found all over the body, but most instances of Follicular Lymphoma tend to appear in the neck, armpit or groin.

Being diagnosed with FL

If your doctor thinks that you might be affected by a blood cancer, you’ll be given tests to help diagnose what type it is. Having these tests doesn’t necessarily mean that you do have cancer – many of the tests can also rule in or rule out other health conditions.

Being diagnosed with any sort of cancer can be a frightening time.. It can be extremely helpful to find out as much information as you can. That’s one of the reasons we’ve created the Follicular Lymphoma Foundation (FLF). Our website contains all of the answers that you might need at every stage of your condition. We’ll also help to connect you with others on their own Follicular Lymphoma journeys, so that you can get support and reassurance from the only other people who can truly understand your experiences.

By arming you with all of the information that you need to understand your condition, explaining medical terms in easy to understand language and introducing you to the FLF community, we hope that you will feel reassured and better prepared for the steps ahead.

The symptoms of Follicular Lymphoma

People with Follicular Lymphoma (FL) often discover an unusual swelling in their neck, armpit or groin that prompts them to visit their doctor. In most cases, they don’t feel unwell or have any other symptoms at all. The normal role of lymph nodes is to fight infection, so a swollen node in the area of an infection, such as a swelling in the neck with a strep throat, is not abnormal, as long as it reduces in size after the infection. However, that doesn’t mean that there aren’t other symptoms associated with Follicular Lymphoma. Others that do occur in some people with FL (and are referred to as B symptoms, not to be confused with B cell lymphoma) include:
  • weight loss (at least 10% of your body weight over six months).
  • fevers (not due to infection).
  • night sweats (drenching, not just a warm feeling or a damp forehead).
Some people with Follicular Lymphoma will experience symptoms including itching, loss of appetite and fatigue, but these are fairly uncommon. Repeated infections can also be seen.

Confirming a diagnosis of Follicular Lymphoma:


There are various tests which may be performed as part of the diagnostic process for Follicular Lymphoma. You may not need every test. Testing will be in addition to a consultation with your doctor who will talk to you about your medical history and what has prompted you to visit them, as well as a physical examination of any swollen lymph glands that you may have.

Let’s take a look at the different diagnostic tests in more detail.


A biopsy is a medical procedure which can be used to determine the type of cells in an unusual growth or swelling. In the case of Follicular Lymphoma and some other cancers, it can also be used to define the grade of disease that you have.

Most biopsies are carried out by a radiologist who will use an ultrasound scan to locate your swollen lymph node. You’ll probably be given a local anaesthetic to keep you comfortable, and then a small sample of your lymph node will be taken with a needle and then sent off to a laboratory to be analysed by a pathologist.

In some cases, a different type of biopsy called an excision biopsy is required. This is where the enlarged lymph node is surgically removed and sent to the lab for analysis. This is actually recommended in most cases of FL.

The results of a biopsy usually take around a week – sometimes longer to be reported. If a diagnosis of Follicular Lymphoma is confirmed, you’ll be referred to a haematologist or oncologist to discuss your next steps.

Blood test

Blood testing is a very common diagnostic tool and can tell your doctor a great deal about your general health, including how well your different organs and body systems are functioning. This can be important for detecting whether you are fighting any active infections, and to check the condition of your health before starting any treatments. Although there is not a specific blood test for lymphoma, you’ll be given general blood testing as part of the diagnostic process. Lymphoma often affects the bone marrow, where blood cells are made, leading to abnormal blood cell counts, such as anemia (low red cells).

CT scan

A CT scan provides a visual picture of the inside of your body and can be used to detect where your lymphoma is. This is used to tell you which stage your lymphoma is at. CT scans are non-invasive and are carried out by radiographers who are specially trained to perform them. You’ll need to lie flat on a special table and a doughnut shaped scanner will move around you to take images of the inside of your body. You won’t feel anything, but you’ll need to stay still for the images to be as clear as possible. You can still talk and will be able to ask your radiographer any questions that you may have during the scan. Your doctor may have you get an intravenous injection just before the scan to help make the images sharper.

PET scan

A PET scan is recommended to help your doctor identify any areas of your body where cancer cells are more active than normal. This is particularly important for people living with cancers like Follicular Lymphoma which can remain dormant for months or years. The PET and CT scans are often done together to give the most information. The process involves injecting a special dye, called a radiotracer, into your body around an hour before your scan. This is done through a small plastic tube called a cannula placed into a vein in your arm. After you’ve been injected, you’ll need to sit for the next hour to allow the dye to spread through your body. Cancer cells develop faster than non-cancerous cells, and during a PET scan, the radiotracer will highlight any areas where this is happening, showing your doctor:
  • if there are any cancer cells in your body.
  • the size of the cancer (in FL often multiple nodes and sometimes the spleen).
  • whether treatment to reduce/eliminate cancer has been successful.

Bone marrow test

A bone marrow test is used to tell your doctor if you have cancer cells present in your bone marrow, where your white blood cells are made.

A bone marrow test is a little more invasive than other diagnostic testing. You’ll be asked to lie on your side as this is the best position to access the bone marrow. Local anaesthetic will be used to numb the area, and then a small sample will be taken using a needle from the back of the hip (really the pelvis bone but often referred to as the hip).

Once the marrow sample has been extracted, it will be sent to the laboratory for examination. This can also take about a week for results to be reported.

Grading and staging Follicular Lymphoma

In order for your doctor to determine the best course of treatment for you, they will need to grade and stage your Follicular Lymphoma.

Grading Follicular Lymphoma

Follicular Lymphoma grades have been used to estimate how your FL may behave. This is done by determining the number of large cells and small cells seen in your diagnostic sample.

Grade 1 has the fewest large cells, with mainly smaller cells being visible. Grade 2 has more large cells; grade 3 even more. Grade 3A has many large cells but still growing in a follicular pattern. Grade 3B has the most large cells, with mainly larger cells visible and a more diffuse growth pattern when viewed under the microscope.

Grades 1 and 2 are the most common and both are considered to be slow-growing lymphoma and are treated in the same way, with the grade number having no effect on your likely outcome. While grade 3A is also considered indolent and usually treated the same way as Grade 1 and 2, it is uncommon and the best approach is not always known.
Grade 3b Follicular Lymphoma is considered as ‘diffuse large B-cell lymphoma’, an aggressive sub-type of lymphoma that is faster-growing, requiring different treatment.

Staging Follicular Lymphoma

Staging is used to identify which areas of your body are affected by Follicular Lymphoma and how far the disease has spread. The stage you are diagnosed with will depend on the location of the tumour, it’s size and how extensively the lymph nodes have been affected.
It is important to understand that, just as normal B cells circulate throughout the body including blood and bone marrow, FL cells do this as well, So, most patients with FL have advanced stage disease at the time of diagnosis. While the concept of staging is useful for many cancers, it is not very useful for blood and lymphatic cancers.

Follicular Lymphoma stage 1

Cancer is limited to one group of lymph nodes, such as those in the neck, armpit or groin.

Follicular Lymphoma stage 2

Two or more groups of lymph nodes are affected, both of which either fall above or below the diaphragm (the muscle separating of the lungs from the abdomen). For example, lymph nodes in the neck and armpit are affected, but not the groin.

Follicular Lymphoma stage 3

Cancer involves two or more groups of lymph nodes and can be found both above and below the diaphragm. For example, lymph nodes in the neck and groin are affected.

Follicular Lymphoma stage 4

Cancer has spread beyond the lymphatic system and is now present outside of lymph nodes, commonly the bone marrow and/or body organs such as the liver.

Once the grade and stage of your Follicular Lymphoma has been determined, your doctor will use these, along with information about your general health, to talk to you about developing a treatment plan. This will outline the goals of your treatment, any potential side effects and what you can expect. They will also be able to answer any of the many questions that you may have about the next stage of your Follicular Lymphoma journey.


After being diagnosed with Follicular Lymphoma, one of the first questions you’ll undoubtedly have will be about what your future looks like. Every cancer is different and Follicular Lymphoma has a better prognosis than many other types.

Here are some helpful statistics.

  • 50% of people with lymphoma will still be alive 20 years after diagnosis.
  • The 5-year survival rate for Stage 4 Follicular Lymphoma cancer has risen from 65% to 88% over the last two decades.

Much of the improvement in the survival rate of advanced Follicular Lymphoma can be attributed to newer treatments, including Rituximab, which was the last major breakthrough in FL treatment that clearly prolonged survival.

Nevertheless, it’s important to be aware that every person living with Follicular Lymphoma is different. Everyone’s FL behaves differently, and for a small percentage of people, their Follicular Lymphoma can be highly resistant to treatment. Unsurprisingly, this has much less favourable outcomes with a much shorter life expectancy.

It’s this unpredictability of Follicular Lymphoma outcomes that has led to researchers and clinicians placing extra focus on improving the accuracy of the prognosis for each individual.. While there are some clinically-based scoring systems already in place, these do not currently provide any guidance on how each patient should be treated.

It’s our hope that a system can be created whereby individual tumour biology and patient details can be combined to provide a much more accurate, personalised prognosis.

“My loneliness, confusion, questions, doubts, fears and happiness are no longer an isolation to me, as I know I am no longer alone! Thank you again [FLF] just for being here.”

Jackie Jean Murphy (diagnosed 2017)